Plasmapheresis/Plasma Exchange/Therapeutic Apheresis

Number: 0285

Table Of Contents

Policy
Applicable CPT / HCPCS / ICD-10 Codes
Background
References


Policy

Scope of Policy

This Clinical Policy Bulletin addresses plasmapheresis, plasma exchange, and therapeutic apheresis.

  1. Medical Necessity

    Aetna considers plasmapheresis (PP), plasma exchange (PE), or therapeutic apheresis medically necessary for any of the following indications:

    1. Acute humoral rejection of renal transplants; or
    2. Acute, severe neurological deficits caused by multiple sclerosis that have a poor response to treatment with high-dose glucocorticoids; or
    3. Anti-neutrophil cytoplasmic antibody-associated vasculitis (Wegener’s granulomatosis, microscopic polyangiitis, Churg-Strauss syndrome) unresponsive to conventional therapy; or
    4. Babesiosis if member has high-grade parasitemia (greater than or equal to 10 %), severe anemia (hemoglobin less than or equal to 10 g/dL), or hepatic, pulmonary, or renal compromise (red blood cell exchange); or
    5. Catastrophic antiphospholipid syndrome (APS with widespread thromboembolic disease and visceral damage); or
    6. Chronic relapsing polyneuropathy (chronic inflammatory demyelinating polyneuropathy [CIDP]) with severe or life-threatening symptoms, in persons who have failed to respond to conventional therapy; Note: Diagnosis of CIDP is documented by symmetric or focal neurological deficits with slowly progressive or relapsing course over 2 or more months with characteristic neurophysiological abnormalities; or
    7. Essential thrombocythemia (when platelet count is greater than 1,000,000/mm3) (platelet pheresis); or
    8. Glomerulonephritis associated with antiglomerular basement membrane antibodies and advancing renal failure or pulmonary hemorrhage; or
    9. Goodpasture’s syndrome (glomerulonephritis associated with antiglomerular basement membrane antibodies and advancing renal failure or pulmonary hemorrhage); or
    10. HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome of pregnancy, if thrombocytopenia, hemolysis, or renal failure continues to worsen 48-72 hours postpartum; or
    11. Hemolytic uremic syndrome; or
    12. Hyperglobulinemias, including (but not limited to) multiple myelomas, cryoglobulinemia, and hyperviscosity syndromes; or
    13. Hypertriglyceridemia-induced acute pancreatitis when the following criteria are met:

      1. Serum triglyceride level greater than 1,000 mg/dL; and
      2. Lipase greater than 3 times the upper limit of normal; and
      3. The member has hypocalcemia, lactic acidosis, or signs of worsening systemic inflammation or organ dysfunction and/or multi-organ failure; or
    14. Last resort treatment of acute disseminated encephalomyelitis, where conventional treatment (including corticosteroids) has failed (i.e., severe neurological deficits have persisted after treatment with corticosteroids); or
    15. Last resort treatment of life-threatening rheumatoid vasculitis; or
    16. Last resort treatment of life-threatening systemic lupus erythematosus (SLE) when conventional therapy has failed to prevent clinical deterioration; or
    17. Leukemia (leukapheresis) (for acute debulking only) including mantle cell lymphoma (mantle cell leukemia) if white blood cells count is greater than 100,000/µL; or
    18. Myasthenia gravis, in persons with any of the following:

      1. Acute, short-term benefit is critical because of a sudden worsening of symptoms (such as in impending respiratory crisis); or
      2. Needs rapid improvement of strength before surgery or irradiation; or
      3. Requires chronic intermittent treatment because of failure to respond to all other treatments; or
      4. Natalizumab-associated progressive multifocal leukoencephalopathy; or
    19. Neuromyelitis optica spectrum disorder (formerly Neuromyelitis optica or Devic's syndrome) that is refractory to glucocorticoids, treatment; or
    20. Paraproteinemic demyelinating neuropathies associated with IgA, IgG or IgM monoclonal gammopathy of undetermined significance (MGUS) (excluding multiple myeloma); or
    21. Pemphigus vulgaris that is resistant to standard therapy (dapsone, corticosteroids, immunosuppressants such as azathioprine or cyclosporine); or
    22. Pruritus from cholestatic liver disease (plasma perfusion of charcoal filters), last resort treatment in persons who have failed (unless contraindicated): bile acid resins (cholestyramine or cholestepol), rifampin, ursodeoxycholic acid (in primary biliary cirrhosis), and opioid antagonists (naltrexone, naloxone or nalmefene); or
    23. Recurrence of focal and segmental glomerulosclerosis in the kidney allograft; or
    24. Refsum's disease; or
    25. Renal transplantation from live donor with ABO incompatibility or positive cross-match, where a suitable non-reactive live or cadaveric donor is unavailable; or
    26. Scleroderma and polBiymyositis, in persons who are unresponsive to conventional therapy; or
    27. Severe (grades 3 to 5) Guillain Barre' syndrome (consistent with guidelines from the American Academy of Neurology, it is generally considered medically necessary to initiate PE within 2 weeks of onset of neuropathic symptoms for ambulant individuals and within 4 weeks of symptom onset for non-ambulant individuals); or
    28. Severe hypercholesterolemia in persons refractory to diet and maximum drug therapy who are homozygous for familial hypercholesterolemia (LDL apheresis, also known as heparin-induced extracorporeal LDL precipitation (HELP) or dextra sulfate adsorption) with LDL levels greater than 500 mg/dL, or persons heterozygous for familial hypercholesterolemia with LDL levels greater than 300 mg/dL or greater than 200 mg/dL with documented history of coronary artery disease.

      Note: For this policy, maximum drug therapy is defined as a 6-month trial of diet plus maximum tolerated combination drug therapy (defined as a trial of drugs from at least 2 separate classes of hypolipidemic agents such as bile acid sequestrants, HMG-CoA reductase inhibitors, fibric acid derivatives, or niacin/nicotinic acids). Documented history of coronary artery disease is defined as a history of myocardial infarction: coronary artery bypass surgery; percutaneous transluminal coronary angioplasty; alternative revascularization procedure; or angina with coronary artery disease documented by stress test. The frequency of LDL apheresis that is considered medically necessary varies, but typically averages about once every 2 weeks to obtain an intrapheresis level of low density lipoprotein cholesterol (LDL-C) of 120 mg/dL or less. It may be considered medically necessary to treat individuals with homozygous familial hypercholesterolemia more frequently.;

    29. Sickle cell disease (therapeutic cytopheresis); or
    30. Solid organ transplant from donor with positive cross-match, where a suitable non-reactive donor is unavailable; or
    31. Thrombotic thrombocytopenic purpura (TTP) or microangiopathic hemolytic anemia, treatment; or
    32. Transverse myelitis treatment when corticosteroid treatment has failed; or
    33. Waldenstrom's macroglobulinemia, prophylactic treatment in persons with IgM greater than or equal to 5000 mg/dL while on rituximab or ofatumumab mg/dL, to avoid aggravation of serum viscosity on the basis of IgM flare related to rituximab or ofatumumab.
  2. Experimental and Investigational

    The following interventions are considered experimental and investigational because the effectiveness of these approaches has not been established:

    1. PP/PE or therapeutic apheresis for all other indications, including the following conditions (not an all-inclusive list) because the medical literature does not support the value of PP/PE or therapeutic apheresis for these indications:

      1. Acute pancreatitis related to hyperlipidemia
      2. Alzheimer's disease
      3. Amyotrophic lateral sclerosis
      4. Anti-MAG neuropathy
      5. Autoimmune inner ear disease
      6. Bullous pemphigoid
      7. Chronic fatigue syndrome
      8. Chronic progressive or secondary progressive multiple sclerosis (maintenance therapy)
      9. Chronic urticaria
      10. Hashimoto's encephalopathy
      11. Hemoglobin Buenos Aires
      12. Heparin-induced thrombocytopenia
      13. Hypertriglyceridemia
      14. Idiopathic myopathy
      15. Idiopathic progressive polyneuropathy
      16. Idiopathic sudden hearing loss
      17. Idiopathic thrombocytopenic purpura
      18. Lupus nephritis
      19. Macular degeneration
      20. Miller Fisher syndrome
      21. Multifocal motor neuropathy (MMN)
      22. Multiple myeloma
      23. Necrobiotic xanogranulomatous skin disorder
      24. Nephrogenic systemic fibrosis
      25. Neuropathy associated with immunoglobulin M gammopathy
      26. Neuropsychiatric symptoms associated with pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS)
      27. Obsessive-compulsive disorder
      28. Optic neuritis
      29. Paraneoplastic syndromes including Eaton-Lambert syndrome and paraproteinemic polyneuropathy
      30. Parkinson’s disease
      31. Postural orthostatic tachycardia syndrome
      32. Psoriasis
      33. Pulmonary alveolar proteinosis
      34. Raynaud's phenomenon
      35. Reducing perioperative blood transfusion
      36. Regional enteritis
      37. Schizophrenia
      38. Secondary polycythemia
      39. Sepsis or septic shock
      40. Snakebite-associated thrombotic microangiopathy
      41. Status epilepticus
      42. Stiff-person syndrome
      43. Sydenham's chorea
      44. Ulcerative colitis (granulocyte and monocyte apheresis for induction and maintenance of clinical remission)
      45. Urticarial vasculitis.
    2. High-density lipoprotein (HDL) delipidation and plasma re-infusion for acute coronary syndrome and all other indications.

  3. Related Policies


Table:

CPT Codes / HCPCS Codes / ICD-10 Codes

Code Code Description

Plasmapheresis (PP) or plasma exchange (PE) :

CPT codes covered if selection criteria are met:

36514 Therapeutic apheresis: for plasma pheresis

CPT codes not covered for indications listed in the CPB:

0342T Therapeutic apheresis with selective HDL delipidation and plasma reinfusion

Other CPT codes related to the CPB:

83690 Lipase
84478 Triglycerides
93015 - 93018 Cardiovascular stress test

Other HCPCS codes related to the CPB:

J2323 Natalizumab, 1 mg
J7500 Azathioprine, oral, 50 mg
J7501 Azathioprine, parenteral, 100 mg
J7502 Cyclosporine, oral, 100 mg
J7515 Cyclosporine, oral, 25 mg
J7516 Cyclosporine, parenteral, 250 mg

ICD-10 codes covered if selection criteria are met:

A81.2 Progressive multifocal leukoencephalopathy [natalizumab-associated]
B60.0 Babesiosis [if member has high-grade parasitemia greater than or equal to 10%]
C88.0 Waldenström macroglobulinemia
C90.0 - C90.02 Multiple myeloma
D47.2 Monoclonal gammopathy [MGUS]
D47.3 Essential (hemorrhagic) thrombocythemia
D59.0 - D59.1 Autoimmune hemolytic anemias
D59.30 - D59.39 Hemolytic-uremic syndrome
D59.4 Other non-autoimmune hemolytic anemias [microangiopathic]
D68.61 Antiphospholipid syndrome
D75.1 Secondary polycythemia
D89.1 Cryoglobulinemias
D89.2 Hypergammaglobulinemia, unspecified [Paraproteinemic demyelinating neuropathies associated with IgA, IgG]
E06.3 Autoimmune thyroiditis
E78.00 - F78.01 Pure hypercholesterolemia [in persons refractory to diet and maximum drug therapy]
G04.00 - G04.02 Acute disseminated encephalitis and encephalomyelitis (ADEM) [where conventional treatment has failed]
G04.81 Other encephalitis and encephalomyelitis [Noninfectious acute disseminated encephalomyelitis (noninfectious ADEM)]
G04.89 Other myelitis (transverse)[ who fail to improve after corticosteroid treatment]
G35 Multiple sclerosis [acute, severe neurological deficits with poor response to treatment with high-dose glucocorticoids] [not covered for chronic or secondary progressive multiple sclerosis (maintenance therapy)]
G36.0 Neuromyelitis optica [Devic]
G37.3 Acute transverse myelitis in demyelinating disease of central nervous system [who fail to improve after corticosteroid treatment]
G60.1 Refsum's disease
G61.0 Guillian-Barre syndrome [covered for severe, grades 3-5 Guillain-Barre syndrome - not covered for Miller Fisher syndrome]
G61.81 Chronic inflammatory demyelinating polyneuritis [CIDP with severe or life threatening symptoms , in persons who have failed to respond ]
G70.00 - G70.01 Myasthenia gravis [acute with sudden worsening of symptoms][needs rapid improvement of strength before surgery or irradiation] [intermittent treatment for failure to respond to all other treatments] [neuropathy associated with immunoglobulin M gammopathy]
I77.6 Arteritis, unspecified [anti-neutrophil cytoplasmic antibody-associated vasculitis unresponsive to conventional therapy]
K71.0 Toxic liver disease with cholestasis
K76.1 Chronic passive congestion of liver [pruritis from cholestatic liver disease]
K76.89 Other specified diseases of liver [pruritis from cholestatic liver disease]
K83.1 Obstruction of bile duct
K85.80 - K85.82 Other acute pancreatitis [hypertriglyceridemia-induced acute pancreatitis]
L10.0 Pemphigus vulgaris [resistant to standard therapy]
L29.0 - L29.8 Pruritus [from cholestatic liver disease]
M05.00 - M05.09 Felty's syndrome
M05.20 - M08.9 Rheumatoid arthritis [moderate to severe active in adults with longstanding who have failed or are intolerant of diseases-modifying anti-rheumatic drugs (DMARDs)]
M30.0 Polyarteritis nodosa
M30.1 Polyarteritis with lung involvement [Churg-Strauss]
M31.0 Hypersensitivity angiitis [Goodpasture's syndrome]
M31.1 Thrombotic microangiopathy
M31.30 - M31.31 Wegener's granulomatosis with or without renal involvement
M32.0 - M32.9 Systemic lupus erythematosus [life threatening, last resort when conventional therapy has failed]
M33.00 - M33.19 Dermatomyositis
M33.20 - M33.29 Polymyositis [in persons unresponsive to conventional therapy]
M34.0 - M34.9 Systemic sclerosis [in persons unresponsive to conventional therapy]
M83.10 - M83.19 Mantle cell lymphoma
N00.0 - N08
N01.A- N07.A
Acute glomerulonephritis, nephrotic syndrome, chronic glomerulonephritis, and nephritis and nephropathy, not specified as acute or chronic [associated with antiglomerular basement membrane antibodies and advancing renal failure or pulmonary hemorrhage]
N18.1 - N19 Chronic kidney disease (CKD) and unspecified renal failure
O14.10 - O14.23 Severe pre-eclampsia and HELLP syndrome [in persons not getting better within 5 days of delivery]
R77.1 Hyperglobulinemias
T86.19 Other complication of kidney transplant [recurrent focal segmental glomerulosclerosis after renal transplantation]

ICD-10 codes not covered for indications listed in the CPB:

A40.0 - A41.9 Streptococcal and other sepsis
C90.00 - C90.02 Multiple myeloma
D58.2 Other hemoglobinopathies [Buenos Aires]
D69.3 Immune thrombocytopenic purpura
D75.1 Secondary polycythemia
D75.821 - D75.829 Heparin induced thrombocytopenia (HIT)
E78.1 Pure hyperglyceridemia
F20.0 – F20.9 Schizophrenia
F42.2 - F42.9 Obsessive-compulsive disorder
G12.21 Amyotrophic lateral sclerosis
G20 - G21.9 Parkinson's disease
G25.82 Stiff-man syndrome
G30.0 - G30.9 Alzheimer's disease
G37.9 Other demyelinating diseases of central nervous system [anti-MAG neuropathy]
G40.011, G40.101, G40.111, G40.201, G40.211, G40.301, G40.311, G40.401, G40.411, G40.501, G40.801, G40.803, G40.811, G40.813, G40.821, G40.823, G40.901, G40.911, G40.A01, G40.A11, G40.B01, G40.B11 Epilepsy and epileptic syndromes, with status epilepticus
G50.0 - G60.0, G60.2 - G60.9, G61.1
G61.89 - G65.2, G70.1. G70.9
Nerve disorders, nerve root and plexus disorders, mononeuritis, neuropathy, and myoneural disorders (except Refsum's disease, Guillain-Barre syndrome, chronic inflammatory demyelinating polyneuritis, and myasthenia gravis) [neuropathy associated with immunoglobulin M gammopathy] [idiopathic progressive polyneuropathy] [anti-MAG neuropathy]
G72.9 Myopathy, unspecified [idiopathic]
H35.30 - H35.379 Degeneration of macula
H46.00 - H46.9 Optic neuritis
H91.20 - H91.23 Sudden idiopathic hearing loss
I02.9 Rheumatic chorea without heart involvement [Sydenham's chorea]
I20.0 Unstable angina [intermediate coronary syndrome]
I73.00 - I73.01 Raynaud's syndrome
J84.01 Alveolar proteinosis
K50.00 - K50.919 Crohns' disease [regional enteritis]
K85.00 - K85.32, K85.90 – K85.92 Acute pancreatitis [related to hyperlipidemia]
L12.0 Bullous pemphigoid
L40.0 - L40.9 Psoriasis
L50.8 Other urticaria [chronic urticaria] [vasculitis]
M31.1 Thrombotic microangiopathy
M35.5 Multifocal fibrosclerosis [nephrogenic systemic fibrosis]
N03.0 Chronic nephritic syndrome with diffuse mesangial proliferative glomerulonephritis [in kidney allograft]
R00.0 Tachycardia, unspecified [postural orthostatic tachycardia syndrome]
R53.82 Chronic fatigue, unspecified
R65.21 Sepsis with septic shock
T63.001A – T63.094S Toxic effect of snake venom

Leukapheresis :

CPT code covered if selection criteria are met:

36511 Therapeutic apheresis: for white blood cells [for acute debulking only]

ICD-10 codes covered if selection criteria are met:

C90.10 - C90.12 Plasma cell leukemia
C91.0 - C95.92 Lymphoid, myeloid, monocytic, other specified, and unspecified leukemias

ICD-10 codes not covered for indications listed in the CPB:

K51.00 - K51.919 Ulcerative colitis

Therapeutic cytopheresis:

CPT code covered if selection criteria are met:

36512 Therapeutic apheresis: for red blood cells

ICD-10 codes covered if selection criteria are met:

D57.00 - D57.819 Sickle-cell disorders

Background

The terms plasmapheresis (PP) and plasma exchange (PE) are often used interchangeably, but when properly used, denote different procedures.  Plasmapheresis refers to a procedure in which the plasma is separated from the blood either by centrifugation or membrane filtration.  Once separated the plasma can be manipulated in a variety of ways.  Plasma exchange refers to discarding the plasma totally and substituting a replacement fluid.  In this assessment PP/PE will be used to describe the combined procedure. 

Therapeutic plasmapheresis (also known as platepheresis or plasma exchange) is performed to remove toxic elements from the bloodstream. An intravenous catheter (small tube) is placed into a vein and connected to a machine (cell separator) via plastic tubing. Blood is pumped through the tubing into the machine where it is separated into red blood cells, white blood cells and plasma. The plasma is then discarded while the other components are combined with a plasma substitute and reinfused into the individual.

Randomized trials have shown that PP/PE is a safe and effective treatment of Guillain Barre syndrome (GBS), particularly if instituted early in the course of disease.  Hughes et al (2007) reported on a systematic evidence review of immunotherapy for GBS.  In 4 trials with altogether 585 severely affected adult participants, those treated with PP/PE improved significantly more on this scale 4 weeks after randomization than those who did not, weighted mean difference (WMD) -0.89 (95 % confidence interval (CI): -1.14 to -0.63).  In 5 trials with altogether 582 participants, the improvement on the disability grade scale with intravenous immunoglobulin (IVIG) was very similar to that with PP/PE, WMD -0.02 (95 % CI: -0.25 to 0.20).  There was also no significant difference between IVIG and PP/PE for any of the other outcome measures.  In 1 trial with 148 participants, following PP/PE with IVIG did not produce significant extra benefit.

Less conclusive information is available regarding PP/PE as a treatment of chronic inflammatory demyelinating polyneuropathy (CIDP); however, this therapy is widely accepted by the medical community.  In a Cochrane systematic evidence review, Mehndiratta et al (2004) identified evidence from 2 small trials showing that PP/PE provides significant short-term benefit in about 2/3 of patients with CIDP but rapid deterioration may occur afterwards.  The authors reported that adverse events related to difficulty with venous access, use of citrate and hemodynamic changes are not uncommon.  The authors noted that a separate Cochrane evidence review found no significant difference in the benefit from PP/PE and IVIG.

Although PP/PE is an accepted treatment of GBS and CIDP, its mechanism of action is still poorly understood.  It is presumed that the symptomatology of these diseases is immune mediated and that PP/PE will remove the pathogenic immune circulating factors.  However, the specific immune factors responsible for the disease have not been identified.  Thus PP/PE is a non selective approach, eliminating the entire plasma.  It should be noted that both these therapies are primarily symptomatic; they do not directly address the production of the pathogenic factors.  Guillain Barre syndrome is an acute self-limited disease; therefore therapy is needed only for a limited period of time.  On the other hand, CIDP is a chronic disease, and PP/PE or IVIG is often needed on a chronic basis.  Physicians titrate the frequency of therapies to the recurrence of symptomatology.

Controlled clinical trials have failed to validate the effectiveness of PP/PE as a treatment of systemic lupus erythematosus (SLE), polymyositis/dermatomyositis and rheumatoid arthritis.  Early small case series of PP/PE as a treatment of rheumatoid vasculitis have not been followed-up with larger controlled studies and no conclusions can be reached as to its effectiveness.  There is minimal information on other autoimmune rheumatic diseases.

There was early enthusiasm for PP/PE as a treatment of chronic rheumatic diseases.  The rationale was based on the fact that humoral factors, such as immunoglobulins or circulating immune complexes, can accumulate in the plasma in rheumatic diseases.  It was hypothesized that the removal of these factors by PP/PE would correct the clinical abnormality.  While PP/PE can indeed lower the serologic level of various disease markers such as circulating immune complexes, anti-DNA antibodies, cryoglobulins or rheumatoid factor, a positive clinical effect on symptomatology has not been demonstrated in clinical trials.  The discrepancy may be related to the fact that PP/PE is essentially a symptomatic treatment.  Although PP/PE may remove circulating immunoglobulins and immune complexes, their local production may persist unabated.

In a systematic review of randomized controlled trials of PP/PE, Shehata et al (2002) identified 8 studies (n = 192), 6 of rheumatoid arthritis and 2 studies of progressive systemic sclerosis (scleroderma).  Plasmapheresis/plasma exchange was not as effective as adjunctive therapy in patients with rheumatoid arthritis.  In addition, there were no benefits for the use of PP/PE in patients with progressive systemic sclerosis.  In 2 studies (n = 140) the addition of PP/PE was not shown to benefit disease activity, the relapse rate, or the number of deaths in patients with polyarteritis nodosa and Churg-Strauss syndrome.  In 7 studies (n = 268), therapeutic PP/PE has not been found to have an additive benefit in SLE patients with active disease or renal disease.

Choy et al (2005) reported on a systematic evidence review of immunotherapy for dermatomyositis and polymyositis.  The investigators reported that 2 randomized placebo-controlled trials assessing PE, leukapheresis and azathioprine produced negative results.  The authors concluded that this systematic review highlights the lack of high quality randomized controlled trials that assess the efficacy and toxicity of immunosuppressants in inflammatory myositis.

Franc et al (2005) reviewed the evidence from randomized controlled clinical trials for treatments for lupus nephritis.  The investigators found, based upon a review of clinical trials, that the current use of cyclophosphamide combined with steroids remains the best option to preserve renal function in proliferative lupus nephritis.  The authors found no benefit with addition of PE to cyclophosphamide or azathioprine plus steroids for mortality (risk ratio [RR] 0.71, 95 % CI: 0.50 to 1.02), doubling of serum creatinine (RR 0.17, 95 % CI: 0.02 to 1.26) or end-stage renal failure (RR 1.24, 95 % CI: 0.60 to 2.57).

Fisher syndrome is one of the regional variants of GBS, characterized by impairment of eye movements (ophthalmoplegia), incoordination (ataxia) and loss of tendon reflexes (areflexia).  It can occur in more limited forms, and may overlap with GBS.  A Cochrane systematic evidence review found no randomized or non-randomized prospective controlled trials of immunotherapy in Fisher Syndrome or related disorders (Overell et al, 2007).  In the largest study of PP/PE for Miller Fisher syndrome reported to date, Mori et al (2002) reported on a retrospective analysis of 50 patients with Miller Fisher syndrome to determine its effect on speed of recovery.  The investigators found no effect of PP/PE on measures of speed of recovery.

There are no proven effective therapies for neuromyelitis optica.  Based on experimental and pathological evidence, it is thought that immunoglobulins and complement deposition are likely to play a role in the pathogenesis of neuromyelitis optica.  Glucocorticoids are typically used to treat cases acutely and may be beneficial.  Azathioprine has been used for subsequent attacks.  Information from the National Institute of Neurological Disorders and Stroke (2007) states that PE may be tried in patients who do not respond to glucocorticoids.  In an uncontrolled case series, 6 of 10 patients with neuromyelitis optica treated with PE showed moderate or marked improvement (Keegan et al, 2002).  A double-blind cross-over study of PP versus sham exchanges found that PP (7 exchanges of approximately 55 ml/kg administered every other day) was beneficial treating exacerbations of demyelinating disease (including neuromyelitis optica) that are not responsive to methylprednisolone (Weinshenker et al, 1999).

Lehmann et al (2008) examined the clinical value of therapeutic PE in the treatment of multi-focal motor neuropathy (MMN).  This study was a retrospective analysis of 7 patients with MMN, who underwent 4 to 18 sessions of PE.  Clinical response, electrophysiological parameter and anti-ganglioside antibody titers were reviewed.  Two patients, who had anti-ganglioside antibodies, exhibited transient clinical responses to PE, manifested by improved neurological function.  Whereas electrophysiological parameters continued to worsen in all patients, anti-ganglioside antibody titers declined during PE, but increased after PE.  The authors concluded that PE is of limited therapeutic value in patients with MMN, who do not respond to established treatment options.  It may only be useful as an adjunctive treatment in a subset of patients.  The transient decrease of anti-ganglioside-antibodies titers suggested that pathogenic humoral factors in MMN are only temporarily reduced.  Further, PE treatment alone is insufficient to prevent axons from continuing degeneration, which may explain the failure of PE to substantially influence the disease course of patients with MMN.

In a Cochrane review, Micheal et al (2009) evaluated the benefits and harms of different interventions for hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP) separately in patients of all ages.  The authors concluded that PE with fresh frozen plasma is still the most effective treatment available for TTP.  For patients with HUS, supportive therapy including dialysis is still the most effective treatment.  All studies in HUS have been conducted in the diarrheal form of the disease.  There were no randomized controlled trials evaluating the effectiveness of any interventions on patients with atypical HUS who have a more chronic and relapsing course.

The Multiple Sklerose Therapie Konsensus Gruppe (2006) stated that the monoclonal antibodies provide considerable improvement of treatment for multiple sclerosis (MS), but their use in basic therapy is restricted by their side effect profile.  Thus, natalizumab is only approved for monotherapy after basic treatment has failed or for rapidly progressive relapsing-remitting MS.  In contrast, long-term data on recombinant beta-interferons and glatiramer acetate (Copaxone) show that even after several years no unexpected side effects occur and that a prolonged therapeutic effect can be assumed which correlates with the dose or frequency of treatment.  Recently IFN-beta1b (Betaferon) was approved for prophylactic treatment after the first attack (clinically isolated syndrome, CIS).  During treatment with beta-interferons, neutralizing antibodies can emerge with possible loss of effectivity.  In contrast, antibodies play no role in treatment with glatiramer acetate.  During or after therapy with mitoxantrone, serious side effects (cardiomyopathy, acute myeloid leukemia) appeared in 0.2 to 0.4 % of cases.  Plasmapheresis is limited to individual curative attempts in escalating therapy of a severe attack.  According to the revised McDonald criteria, the diagnosis of MS can be made as early as the occurrence of the first attack.

Tackenberg et al (2007) stated that the natural course of MS is probably more favorable than previously assumed years ago.  Since the introduction of interferons in Germany, the establishment and further development of new diagnostic criteria (McDonald criteria), the causal and symptomatic treatment possibilities and initiation of therapy early in the course of the disease have led to a considerable change in the treatment of MS.  Attacks of MS are usually treated with the intravenous administration of high-dosed steroids.  When the attack symptoms do not sufficiently subside, PP can be considered.  For long-term treatment of MS, beta interferon, glatirameracetate and natalizumab are available as basic causal therapy and natalizumab and mitoxantrone are available for escalation therapy.  Frequently occurring spasticity, chronic fatigue syndrome, depression, cognitive disturbances, incontinence, pain, ataxia and sexual disorders must be treated symptomatically.  Overall, the outpatient treatment of MS is complex and should be carried out with close co-operation between the family doctor, neurological practices and outpatient departments specialized in treating MS.

Oh et al (2008) noted that B-cells and humoral immunity have been implicated in the pathogenesis of MS.  The most common pattern of demyelinating pathology in MS is associated with the deposition of antibodies and the activation of complement, as well as T-cells and macrophages.  Plasmapheresis has been found to be an efficient therapeutic approach in patients with this type of pathological lesion.

Matsui (2008) noted that Japanese patients with relapsing-remitting multiple sclerosis (RRMS) consists of 2 groups.  One is opticospinal form (OSMS), in which major neurological symptoms derive from optic neuritis and myelitis, and the other is conventional form (CMS) that shares similar genetical and clinical features with western type of MS.  Patients with OSMS tend to experience disease relapses more frequently with the resultant severer neurological deficit than CMS ones.  Both OSMS and CMS patients are treated with intravenous high-dose methylprednisolone in acute exacerbations, and PP may be considered for those who do not respond to repeated intravenous steroids.  For prevention of disease relapse, interferon-beta is effective; however, patients with long spinal cord lesion extending over 3 vertebral segments should be followed-up with caution, as this finding indicates a risk of treatment failure.

Ohji and Nomura (2008) discussed steroid pulse therapy and apheresis therapy indicated for the treatment of MS.  In the basic treatment course for MS, steroid pulse therapy is a 1st-line treatment for RR-MS in the course of the exacerbation, and apheresis therapy is performed in refractory cases.  Treatment strategies for chronic progressive MS are not to be established.  Steroid pulse therapy has been established as a treatment for MS in the active phase through randomized controlled trials (RCT).  Apheresis therapy includes PP and cytapheresis, and PP includes PE and immunoadsorption plasmapheresis (IAPP).  Plasma exchange and IAPP are performed for MS treatment.  The former has been established as a useful treatment for active phase MS.  The efficacy of IAPP has been frequently reported, but no reports have been based on RCT.

Schroder et al (2009) stated that apheresis is a general term that describes removal of abnormal blood constituents by extracorporeal blood purification methods.  To date, therapeutic PE is the most common apheresis procedure.  Here, plasma is separated from corpuscular blood constituents and replaced with a substitution fluid. In contrast to immunoadsorption, PE is a non-specific treatment modality with elimination of the entire plasma.  The therapeutic effect is based on the removal of circulating, pathogenic immune factors including autoantibodies.  Currently, PE is used for treatment of several immune-mediated neurological disorders.  While first experiences relate to acute life-threatening conditions, such as treatment of GBS or myasthenic crisis, therapeutic success was also shown in chronic diseases where immunosuppressive therapy is often required for long-term management.  Plasma exchange has been applied successfully in CIDP, paraproteinemic polyneuropathy, stiff person syndrome, and may also be tried in several diseases of paraneoplastic origin.  In recent years, PE was also established as an escalation therapy for steroid-unresponsive relapses of MS, and thus has gained more widespread attention.

Olek (2009) stated that PE may be beneficial in patients with acute central nervous system (CNS) inflammatory demyelinating disease who do not respond to glucocorticoid therapy.  In the only formally reported clinical trial, 22 patients with CNS demyelinating disease (12 with MS) were randomly assigned to either active PE or sham treatment, with a total of 7 treatments, given every 2 days over 14 days. Moderate or greater improvement in neurologic disability occurred during 8 of 19 (42 %) courses of active treatment compared with 1 of 17 (6 %) courses of sham treatment.  Improvement occurred early in the course of treatment and was sustained on follow-up.  However, 4 of the patients who responded to the active treatment experienced new attacks of demyelination during 6 months of follow-up.  Given these data, the author suggested treatment with PE for patients with acute, severe neurologic deficits caused by MS who have a poor response to treatment with high-dose glucocorticoids.

Ruprecht and colleagues (2004) reviewed a series of 10 consecutive patients treated with PE for acute, severe optic neuritis (ON) largely unresponsive to previous high-dose intravenous glucocorticosteroids.  Plasma exchange was associated with an improvement of visual acuity according to the study criteria in 7 of 10 patients.  On follow-up, 3 of these patients continued to improve, 2 remained stable, and 2 had worsened again.  The authors noted that PE may be beneficial as an escalating treatment in a subset of patients with severe ON; but a controlled trial is needed.  Furthermore, in a review on ON, Osborne and Volpe (2009) stated that data on the use of PE in the treatment of patients with ON are too scarce to make any recommendations.

Boada-Rovira (2010) noted that results from a pilot study and its 2-year extension performed on patients with mild or moderate Alzheimer's disease (AD) revealed a tendency towards clinical stabilization after a PP program with PE with therapeutic albumin Human albumin Grifols 5 %.  Plasma levels of alphabeta(40) and alphabeta(42) presented a saw-tooth pattern associated to PE.  These findings encouraged a new randomized, controlled, parallel, blind study to confirm the previous working hypotheses, i.e., that alphabeta(40) and alphabeta(42) concentrations in plasma were modified pre- and post-PP with human albumin Grifols 5 % and, in the clinical area, that the cognitive capabilities of patients could be stabilized or even improved.  Other aims of the study were focused on neuroimaging evaluation of structural and functional changes in the brain the by means of magnetic resonance and single-photon emission computerized tomography.  Preliminary results from the randomized study performed after a follow-up of 1 year of the first 29 patients (80 % of the recruited) show a clear difference between the treated and the control groups with regard to the levels of alphabeta(40), both in plasma and in cerebrospinal fluid, that are associated with the PE.  This pattern is not so evident for alphabeta(42).  Regarding cognitive performance, the treated group scored better than the control group after the period study, according to the evaluation performed by using the Mini-Mental State Examination (MMSE) and AD Assessment Scale-Cognitive (ADAS-Cog) tests.  The authors concluded that these preliminary results suggested that PP with PE with human albumin Grifols 5 % may have a promising future as a treatment of mild-moderate AD.

In a Cochrane review, Kirtschig et al (2010) evaluated treatments for bullous pemphigoid (BP); RCTs of treatments for subjects with immunofluorescence-confirmed BP were included in this analysis.  At least 2 authors evaluated the studies for the inclusion criteria, and extracted data independently.  A total of 10 RCTs (with a total of 1,049 participants) of moderate-to-high risk of bias were selected.  All studies involved different comparisons, none had a placebo group.  In 1 trial PE plus prednisone gave significantly better disease control at 1 month (0.3 mg/kg: RR 18.78, 95 % CI: 1.20 to 293.70) than prednisone alone (1.0 mg/kg: RR 1.79, 95 % CI: 1.11 to 2.90), while another trial showed no difference in disease control at 6 months.No differences in disease control were seen for different doses or formulations of prednisolone (1 trial each), for azathioprine plus prednisone compared with prednisone alone (1 trial), for prednisolone plus azathioprine compared with prednisolone plus PE (1 trial), for prednisolone plus mycophenolate mofetil or plus azathioprine (1 trial), for tetracycline plus nicotinamide compared with prednisolone (1 trial).  Chinese traditional medicine plus prednisone was not effective in 1 trial.  There were no significant differences in healing in a comparison of a standard regimen of topical steroids (clobetasol) with a milder regimen (RR 1.00, 95 % CI: 0.97 to 1.03) in 1 trial.  In another trial, clobetasol showed significantly more disease control than oral prednisolone in people with extensive and moderate disease (RR 1.09, 95 % CI: 1.02 to 1.17), with significantly reduced mortality and adverse events (RR 1.06, 95 % CI: 1.00 to 1.12).  The authors concluded that very potent topical steroids are effective and safe treatments for BP, but their use in extensive disease may be limited by side-effects and practical factors.  Milder regimens (using lower doses of steroids) are safe and effective in moderate BP.  Starting doses of prednisolone greater than 0.75 mg/kg/day do not give additional benefit, lower doses may be adequate to control disease and reduce the incidence and severity of adverse reactions.  The effectiveness of adding PE, azathioprine or mycophenolate mofetil to corticosteroids, and combination treatment with tetracycline and nicotinamide needs further investigation.

In January 2011, the American Academy of Neurology (AAN) published a new guideline on PP in neurologic disorders (Cortese et al, 2011).  It states that PP/PE can be used as 2nd-line treatment of steroid-resistant exacerbations in relapsing forms of MS.  Moreover, PP is established as ineffective and should not be offered for chronic or secondary progressive MS.  The guideline also stated that PP is probably not effective and should not be considered for neuropathy associated with immunoglobulin M gammopathy.

The AAN (Scott et al, 2011) evaluated the evidence for diagnostic tests and therapies for transverse myelitis (TM) and made evidence-based recommendations.  A review of the published literature from 1966 to March 2009 was performed, with evidence-based classification of relevant articles.  Level B recommendations: Neuromyelitis optica (NMO)-immunoglobulin G (IgG) antibodies should be considered useful to determine TM cause in patients presenting with clinical acute complete transverse myelitis (ACTM) features.  The presence of NMO-IgG antibodies (aquaporin-4-specific antibodies) should be considered useful in determining increased TM recurrence risk.  Level C recommendations: In suspected TM, distinction between ACTM or acute partial transverse myelitis may be considered useful to determine TM etiology and risk for relapse (more common with APTM).  Age and gender may be considered useful to determine etiology in patients presenting with TM syndrome, with spinal infarcts seen more often in older patients and more female than male patients having TM due to MS.  Brain MRI characteristics consistent with those of MS may be considered useful to predict conversion to MS after a first partial TM episode.  Longer spinal lesions extending over more than 3 vertebral segments may be considered useful in determining NMO versus MS.  Cerebrospinal fluid examination for cells and oligoclonal bands may be considered useful to determine the cause of the TM syndrome.  Plasma exchange may be considered in patients with TM who fail to improve after corticosteroid treatment.  Rituximab may be considered in patients with TM due to NMO to decrease the number of relapses.  Level U recommendations: There is insufficient evidence to support or refute the efficacy of other TM therapies or the usefulness of ethnicity to determine the cause of a subacute myelopathy.

An UpToDate review on “Clinical manifestations, diagnosis, treatment, and prevention of babesiosis” (Gelfand and Vannier, 2012) states that “Partial or complete red cell exchange transfusion is appropriate for patients with high-grade parasitemia (≥10 percent), severe anemia (hemoglobin ≤10 g/dL), or pulmonary, renal, or hepatic compromise …. Exchange transfusion is intended to clear the systemic compartment of infected red blood cells, to remove inflammatory mediators and toxic by-products of cell lysis, and to correct anemia.  Management of exchange transfusion should be handled in close consultation with experts in hematology and pheresis.  A single red cell exchange may be adequate, but multiple exchanges may be needed.  A 90 percent reduction in parasitemia has been proposed as the desired target of red blood cell exchange in babesiosis.  The volume of allogeneic red cells required to achieve such reduction in parasitemia is predicted to be 2.5 times the estimated volume of recipient’s red blood cells”.

In a Cochrane review, Carless et al (2011) examined the evidence for the efficacy of platelet-rich plasmapheresis (PRP) in reducing peri-operative allogeneic red blood cell (RBC) transfusion, and the evidence for any effect on clinical outcomes such as mortality and re-operation rates.  These investigators identified studies by searching MEDLINE (1950 to 2009), EMBASE (1980 to 2009), the Cochrane Library (Issue 1, 2009), the Internet (to March 2009) and the reference lists of published articles, reports, and reviews.  Controlled parallel group trials in which adult patients, scheduled for non-urgent surgery, were randomized to PRP, or to a control group that did not receive the intervention were selected for analysis.  Primary outcomes measured were: the number of patients exposed to allogeneic RBC transfusion, and the amount of RBC transfused.  Other outcomes measured were: the number of patients exposed to allogeneic platelet transfusions, fresh frozen plasma, and cryoprecipitate, blood loss, re-operation for bleeding, post-operative complications (thrombosis), mortality, and length of hospital stay.  Treatment effects were pooled using a random-effects model.  A total of 22 trials of PRP were identified that reported data for the number of patients exposed to allogeneic RBC transfusion.  These trials evaluated a total of 1,589 patients.  The relative risk (RR) of exposure to allogeneic blood transfusion in those patients randomized to PRP was 0.73 (95 % CI: 0.59 to 0.90), equating to a relative risk reduction (RRR) of 27 % and a risk difference (RD) of 19 % (95 % CI: 10 % to 29 %).  However, significant heterogeneity of treatment effect was observed (p < 0.00001; I² = 79 %).  When the 4 trials by Boldt were excluded, the RR is 0.76 (95 % CI: 0.62 to 0.93).  On average, PRP did not significantly reduce the total volume of RBC transfused (weighted mean difference [WMD] -0.69, 95 %CI: -1.93 to 0.56 units).  Trials provided inadequate data regarding the impact of PRP on morbidity, mortality, and hospital length of stay.  Trials were generally small and of poor methodological quality.  The authors concluded that although the results suggested that PRP is effective in reducing allogeneic RBC transfusion in adult patients undergoing elective surgery, there was considerable heterogeneity of treatment effects and the trials were of poor methodological quality.  They stated that the available studies provided inadequate data for firm conclusions to be drawn regarding the impact of PRP on clinically important endpoints.

The American Academy of Child and Adolescent Psychiatry’s practice parameter for the assessment and treatment of children and adolescents with obsessive-compulsive disorder (AACAP, 2012) stated that “Therapeutic plasma exchange and intravenous immunoglobulin remain experimental interventions with substantial risk and potential morbidity”.

Hanna and Wong (2013) stated that sepsis remains an important challenge in pediatric critical care medicine.  These investigators provided an appraisal of adjunctive therapies for sepsis and high-lighted opportunities for meeting selected challenges in the field.  The authors stated that future clinical studies should address long-term and functional outcomes as well as acute outcomes.  Potential adjunctive therapies such as corticosteroids, hemo-filtration, hemo-adsorption, and PP may have important roles, but still require formal and more rigorous testing by way of clinical trials.

Low high-density lipoprotein (HDL) is associated with increased risk of cardiovascular disease.  Plasma selective delipidation converts alphaHDL to prebeta-like HDL, the most effective form of HDL for lipid removal from arterial plaques.

Tardif et al (2007) investigated the effects of reconstituted HDL on plaque burden as assessed by intra-vascular ultrasound (IVUS).  Between July 2005 and October 2006, a total of 183 patients had a baseline IVUS examination and of those, 145 had evaluable serial IVUS examinations after 6 weeks.  A total of 60 patients were randomly assigned to receive 4 weekly infusions of placebo (saline); 111 to receive 40 mg/kg of reconstituted HDL (CSL-111); and 12 to receive 80 mg/kg of CSL-111.  The primary efficacy parameter was the percentage change in atheroma volume.  Nominal changes in plaque volume and plaque characterization index on IVUS and coronary score on quantitative coronary angiography were also pre-specified end-points.  The higher-dosage CSL-111 treatment group was discontinued early because of liver function test abnormalities.  The percentage change in atheroma volume was -3.4 % with CSL-111 and -1.6 % for placebo (p = 0.48 between groups, p < 0.001 versus baseline for CSL-111).  The nominal change in plaque volume was -5.3 mm3 with CSL-111 and -2.3 mm3 with placebo (p = 0.39 between groups, p < 0.001 versus baseline for CSL-111).  The mean changes in plaque characterization index on IVUS (-0.0097 for CSL-111 and 0.0128 with placebo) and mean changes in coronary score (-0.039 mm for CSL-111 and -0.071 mm with placebo) on quantitative coronary angiography were significantly different between groups (p = 0.01 and p = 0.03, respectively).  Administration of CSL-111 40 mg/kg was associated with mild, self-limiting transaminase elevation but was clinically well-tolerated.  The authors concluded that short-term infusions of reconstituted HDL resulted in no significant reductions in percentage change in atheroma volume or nominal change in plaque volume compared with placebo, but did result in statistically significant improvement in the plaque characterization index and coronary score on quantitative coronary angiography.  They stated that elevation of HDL remains a valid target in vascular disease and further studies of HDL infusions including trials with clinical end-points are needed.

Waksman et al (2010) examined if serial autologous infusions of selective HDL delipidated plasma are feasible and well-tolerated in patients with acute coronary syndrome (ACS).  Patients with ACS undergoing cardiac catheterization with greater than or equal to 1 non-obstructive native coronary artery atheroma were randomized to either 7 weekly HDL selective delipidated or control plasma apheresis/reinfusions.  Patients underwent IVUS evaluation of the target vessel during the catheterization for ACS and up to 14 days following the final apheresis/reinfusion session.  Two-dimensional gel electrophoresis of delipidated plasmas established successful conversion of alphaHDL to prebeta-like HDL.  The trial was complete with 28 patients randomized.  All reinfusion sessions were tolerated well by all patients.  The levels of prebeta-like HDL and alphaHDL in the delipidated plasma converted from 5.6 % to 79.1 % and 92.8 % to 20.9 %, respectively.  The IVUS data demonstrated a numeric trend toward regression in the total atheroma volume of -12.18 +/- 36.75 mm(3) in the delipidated group versus an increase of total atheroma volume of 2.80 +/- 21.25 mm(3) in the control group (p = 0.268).  The authors concluded that in ACS patients, serial autologous infusions of selective HDL delipidated plasma are clinically feasible and well-tolerated.  They stated that this therapy may offer a novel adjunct treatment for patients presenting with ACS.  Moreover, they stated that further investigation is needed to determine its ability to reduce clinical cardiovascular events.

An UpToDate review on “HDL metabolism and approach to the patient with abnormal HDL-cholesterol levels” (Rosenson and Durrington, 2013) cited the study by Tardif et al (2007) and listed infusion of reconstituted HDL as an investigational therapy.  Moreover, the review does not mention HDL delipidation and plasma re-infusion as a therapeutic option.

Guidelines from the National Comprehensive Cancer Network (NCCN, 2014) on Waldenstrom's Macroglobulinemia/Lymphoplasmacytic Lymphoma state that plasmapheresis should be performed for patients with symptomatic hyperviscosity, and before treatment with rituximab or ofatumumab containing regimen in patients with patients with IgM greater than or equal to 5000 mg/dL on ritxumab-containing therapy to avoid aggravation of serum viscosity on the basis of rituximab-containing IgM flare. The guidelines state that rituximab or ofatumumab may also be held in patients with elevated serum IgM levels for initial treatment cycles. 

Current guidelines recommend plasmapheresis for acute hemoral rejection of renal transplants. Kidney Disease: Improving Global Outcomes (KDIGO) clinical guidelines suggest treating antibody-mediated acute rejection with one or more of the following alternatives, with or without corticosteroids (2C recommendation):  plasma exchange; intravenous immunoglobulin; anti-CD20 antibody; or lymphocyte-depleting antibody (Kasiske, et al, 2009). European Association of Urology guidelines on renal transplantation (Kälble, et al, 2009) state that treatment of acute humoral rejection of a renal transplant may include steroid bolus therapy, conversion to tacrolimus, antibody elimination and intravenous immunoglobulin (Grade B recommendation). Guidelines from the Renal Association (Baker, et al, 2011) suggest that antibody mediated rejection should be treated with one or more of the following modalities: steroids; plasma exchange; intravenous immunoglobulin; anti-CD20 antibody; or lymphocyte-depleting antibody (2C recommendation).

Brouet et al (1990) stated that monoclonal IgM from patients with peripheral neuropathy react in nearly 80 % of the cases with some components of myelin.  The main target is myelin associated glycoprotein (50 % of the cases); several types of glycolipids or gangliosides have been identified as the reactive antigen in the other cases.  Anti-MAG IgM shared little cross reactive idiotopes.  Only primate anti-sera identified a combining site related public idiotope.  In fact, these IgM used various light and heavy chains belonging to different variability subgroups.  The authors concluded that the preliminary results of an ongoing trial aimed to establish the benefit of plasmapheresis in these patients.

Rimmer et al (2014) evaluated the safety and effectiveness of PE in patients with sepsis.  These investigators searched MEDLINE, EMBASE, CENTRAL, Scopus, reference lists of relevant articles, and grey literature for relevant citations.  They included RCTs comparing PE or plasma filtration with usual care in critically ill patients with sepsis or septic shock.  Two reviewers independently identified trials, extracted trial-level data and performed risk of bias assessments using the Cochrane Risk of Bias tool.  The primary outcome was all-cause mortality reported at longest follow-up.  Meta-analysis was performed using a random-effects model.  Of 1,957 records identified, these researchers included 4 unique trials enrolling a total of 194 patients (1 enrolling adults only, 2 enrolling children only, 1 trial enrolling adults and children).  The mean age of adult patients ranged from 38 to 53 years (n = 128) and the mean age of children ranged from 0.9 to 18 years (n = 66).  All trials were at unclear to high risk of bias.  The use of PE was not associated with a significant reduction in all-cause mortality (RR 0.83, 95 % CI: 0.45 to 1.52, I2 60 %).  In adults, PE was associated with reduced mortality (RR 0.63, 95 % CI: 0.42 to 0.96; I2 0 %), but was not in children (RR 0.96, 95 % CI: 0.28 to 3.38; I2 60 %).  None of the trials reported ICU or hospital lengths of stay.  Only 1 trial reported adverse events associated with PE including 6 episodes of hypotension and 1 allergic reaction to fresh frozen plasma.  The authors concluded that insufficient evidence exists to recommend PE as an adjunctive therapy for patients with sepsis or septic shock.  They stated that rigorous RCTs evaluating clinically relevant patient-centered outcomes are needed to evaluate the impact of PE in this condition.

Hildebrand et al (2014) stated that therapeutic PE (TPE) has been used as adjunctive therapy for various kidney diseases dating back to the 1970s.  In many cases, support for TPE was on mechanistic grounds given the potential to remove unwanted large molecular-weight substances such as autoantibodies, immune complexes, myeloma light chains, and cryoglobulins.  More recently, growing evidence from RCTs, meta-analyses, and prospective studies has provided insights into more rational use of this therapy.  These investigators described the role of TPE for the 6 most common kidney indications in the 2013 Canadian Apheresis Group (CAG) registry and the evidence that under-pined current recommendations and practice.  These kidney indications include
  1. thrombotic microangiopathy,
  2. antiglomerular basement membrane disease,
  3. anti-neutrophil cytoplasmic antibody-associated vasculitis,
  4. cryoglobulinemia,
  5. recurrence of focal and segmental glomerulosclerosis in the kidney allograft, and
  6. kidney transplantation.

The Society of Obstetricians and Gynecologists of Canada’s guideline on “Treatment of the hypertensive disorders of pregnancy” (Magee et al, 2014) states that “The following interventions were considered but not recommended or there was insufficient evidence to make a recommendation: plasma exchange or plasmapheresis for HELLP syndrome …. The guideline developers recommend against plasma exchange or plasmapheresis for hemolysis, elevated liver enzymes, low platelets syndrome, particularly within the first 4 days postpartum”. SOGC guidelines note insufficient evidence for plasma exchange or plasmapheresis, noting that observational studies have suggested improved hematological and biochemical indicators, but small RCTs have found no maternal or perinatal outcome improvement.

Also, an UpToDate review on “HELLP syndrome” (Sibai, 2014) does not mention plasmapheresis, plasma exchange, or therapeutic apheresis as therapeutic options.

By contrast, guidelines from the American Society of Hematology (Rajasekhar, et al, 2013) recommend the use of plasma exchange in HELLP syndrome if thrombocytopenia, hemolysis, or renal failure continues to worsen 48 to 72 hours postpartum.

A review by Gernsheimer, et al (2013) recommends plasma exchange if thrombocytopenia, hemolysis, or renal failure continues to worsen 48-72 hours postpartum and differentiating between preeclampsia/HELLP/AFLP and thrombotic thrombocytopenic purpura (TTP)/atypical hemolytic uremic syndrome that can follow a normal pregnancy becomes difficult, if not impossible. The authors noted that several case series suggest that the use of plasma exchange treatment may improve the outcome of both severe HELLP and AFLP.

Pagano et al (2014) noted that the effectiveness of TPE in stiff-person syndrome (SPS) is unclear.  These researchers performed a retrospective analysis of patients diagnosed with SPS who underwent TPE and a systematic literature review.  A total of 9 patients with the presumptive diagnosis of SPS who underwent TPE were identified.  The mean age was 55 years (range of 34 to 72 years) and 78 % (n = 7) were female.  Anti-GAD65 was present in 89 % (n = 8) of the patients (range of 1.9 to 40,000 U/ml), and 33 % (n = 3) had a history of diabetes; 44 % (n = 4) of patients had previously received immunosuppressive medication and 67 % (n = 6) received IVIG.  The main indication for TPE was worsening of symptoms despite treatment with first-line therapy; 78 % of the patients (n = 7) had 5 TPE procedures; 78 % (n = 7) of patients demonstrated at least minimal clinical improvement and 56 % (n = 5) had a significant response.  Most of the patients who demonstrated a significant response to treatment improved and their symptoms stabilized.  Two patients (22 %) developed adverse events, including catheter-associated infection and transient hypotension.  A total of 18 publications were found from the literature review, which resulted in a total of 26 patients diagnosed with SPS; 42 % (n = 11) of patients had a significant symptomatic improvement after TPE treatment, and 2 patients (8 %) developed adverse events.  The authors concluded that TPE may benefit patients with SPS who are not responsive to first-line therapy, and it is well-tolerated.  These preliminary findings need to be validated by well-designed studies.

Anti-Phospholipid Syndrome

Kronbichler et al (2016) noted that extracorporeal treatments have been used since the 1970s in the management of systemic lupus erythematosus (SLE).  A RCT comparing the effectiveness of standard of care (SOC) combined with PE against SOC alone in patients with lupus nephritis revealed no difference in terms of renal outcome.  Subsequently, initial expectations have been dampened and further experience with PE is mainly limited to observational studies and single-case reports.  Beneficial effects have been reported in patients with refractory disease course or in pregnancy with prior complications due to SLE and anti-phospholipid syndrome (APS).  A more specific form of extracorporeal treatment, immunoadsorption (IAS), has emerged as a valuable option in the treatment of SLE.  In line with the PE experience, IAS seems to have beneficial effects in patients with refractory disease, contraindications to standard immunosuppression or during pregnancy.  The mechanism IAS relates to autoantibody removal but for PE removal of activated complement components, coagulation factors, cytokines and micro-particles may also be relevant.  Both treatment forms have good safety profiles although reactions to blood product replacement in PE and procedure related complications such as bleeding or catheter-related infections have occurred.  The authors concluded that there is a need to more clearly define the clinical utility of PE and IAS in refractory lupus and APS subgroups.

Furthermore, an UpToDate review on “Therapeutic apheresis (plasma exchange or cytapheresis): Indications and technology” (Fridey and Kaplan, 2016) does not mention APS as an indication of therapeutic apheresis. 

Hypertriglyceridemia

Valdivielso and colleagues (2014) noted that severe hypertriglyceridemia (HTG) is a well-established and the most common cause of acute pancreatitis (AP) after alcohol and gall stone disease.  It is alleged to account for up to 10 % of all pancreatitis episodes.  Studies suggested that in patients with triglyceride (TG) levels greater than 1,000 mg/dL (> 11.3 mmol/L), HTG-induced AP (HTGP-AP) occurs in approximately 15 to 20 % of all subjects referred to Lipid Clinics.  Until now, there is no clear evidence which patients with severe HTG will develop pancreatitis and which will not.  Underlying pathophysiological concepts include hydrolysis of TG by pancreatic lipase and excessive formation of free fatty acids with inflammatory changes and capillary injury.  Additionally hyper-viscosity and ischemia may play a decisive role.  The clinical features of HTG-AP patients are supposed to be no different from patients with AP of other etiologies.  Yet, there are well-conducted studies suggesting that HTG-AP is associated with a higher severity and complication rate.  Therapeutic approaches in HTG-AP include dietary modifications, different anti-hyperlipidemic agents, insulin and/or heparin treatment.  The beneficial use of plasmapheresis is repeatedly reported and suggested in many studies. Yet, due to the lack of randomized and controlled trials (RCTs), it is currently unknown if plasmapheresis may improve morbidity and mortality in the clinical setting of HTG-AP.  Since there are no commonly accepted clinical guidelines in the management of HTG-AP, there is a definite need for an international, multi-center approach to this important subject.

Scherer et al (2014) stated that HTG is a well-established but under-estimated cause of AP and recurrent AP.  The clinical presentation of HTG-induced pancreatitis (HTG pancreatitis) is similar to other causes.  Pancreatitis secondary to HTG is typically seen in the presence of 1 or more secondary factors (uncontrolled diabetes, alcoholism, medications, pregnancy) in a patient with an underlying common genetic abnormality of lipoprotein metabolism (familial combined hyperlipidemia or familial HTG).  Less commonly, a patient with rare genetic abnormality (familial chylomicronemic syndrome) with or without an additional secondary factor is encountered.  The risk of AP in patients with serum triglycerides greater than 1,000 and greater than 2,000 mg/dL is approximately 5 % and 10 % to 20 %, respectively.  It is not clear whether HTG pancreatitis is more severe than when it is due to other causes.  Clinical management of HTG pancreatitis is similar to that of other causes.  Insulin infusion in diabetic patients with HTG can rapidly reduce TG levels.  Use of apheresis is still experimental and better designed studies are needed to clarify its role in the management of HTG pancreatitis.  Diet, lifestyle changes, and control of secondary factors are key to the treatment, and medications are useful adjuncts to the long-term management of TG levels.  Control of TG levels to 500 mg/dL or less can effectively prevent recurrences of pancreatitis.

Click et al (2015) stated that mostly published as case reports or series, the role of apheresis in HTG-related AP remains unclear.  These investigators performed a systematic review of available literature on this topic with specific focus on disease severity.  A search of electronic databases (PubMed, EMBASE, Cochrane) and gray literature yielded 5,020 articles of which 74 met criteria for inclusion (301 unique patients).  Relevant data were abstracted from full manuscripts and analyzed.  Most patients were young (mean age of 37.9 ± 10.4 years) and male (71.5 %).  About 2/3 (69.7 %) received apheresis within 48 hrs and most required only 1 or 2 sessions (84.4 %).  Apheresis resulted in an average reduction of serum TG by 85.4 % (p < 0.001).  There was high variability in reporting the presence of and criteria to define severe AP (reported 221/301, 73.4 %; present 85/221, 38.5 %) or organ failure (reported 104/301, 34.6 %; present 52/104, 50.0 %).  Improvement was reported in the majority of patients (reported 144/301, 47.8 %, present 136/144, 94.4 %) mainly by clinical symptoms or laboratory tests.  Overall mortality was 7.1 % (21/294) which increased to 11.8 % (10/85) with severe AP and 19.2 % (10/52) with organ failure.  The authors concluded that apheresis effectively reduced serum TG levels.  However, due to uncontrolled data, reporting bias and lack of a comparison group, definitive conclusions on the efficacy of apheresis in reducing AP severity cannot be made.  These researchers proposed which patients may be best suitable for apheresis, type of studies needed and outcome measures to be studied in order to provide empiric data on the role of apheresis in HTG-related AP.

An UpToDate review on “Hypertriglyceridemia-induced acute pancreatitis” (Gelrud and Whitcomb, 2016) states that “Apheresis -- Apheresis is a term describing the general process of passing blood through a medical device to separate any components, and returning the remaining components to the body.  Plasmapheresis is the removal of up to 15 % of the plasma, filtration uses a membrane to remove components by size, and therapeutic plasma exchange (TPE) is the removal of plasma and replacement with a colloid solution (e.g., albumin or plasma).  TPE is the treatment modality of choice for HTGP when apheresis is needed because filters become clogged by plasma triglycerides …. We suggest treatment with apheresis, and specifically therapeutic plasma exchange (TPE) if the patient has a serum triglyceride level > 1,000 mg/dL plus lipase > 3 times the upper limit of normal and signs of hypocalcemia, lactic acidosis, or signs of worsening inflammation or organ dysfunction, and if there are no contraindications to apheresis (Grade 2C)”.

IgG and IgA Paraproteinaemic Neuropathy

In a Cochrane review, Stork et al (2015) examined the effects of any treatment for IgG or IgA paraproteinaemic peripheral neuropathy.  On January 18, 2014 these investigators searched the Cochrane Neuromuscular Disease Group Trials Specialized Register, CENTRAL, MEDLINE and EMBASE.  They also checked bibliographies for controlled trials of treatments for IgG or IgA paraproteinaemic peripheral neuropathy.  These researchers checked clinical trials registries for ongoing studies in November 2014.  They considered for inclusion RCTs and quasi-RCTs using any treatment for IgG or IgA paraproteinaemic peripheral neuropathy.  They excluded people with IgM paraproteins.  They excluded people where the monoclonal gammopathy was considered secondary to an underlying disorder.  They included participants of any age with a diagnosis of monoclonal gammopathy of uncertain significance with a paraprotein of the IgG or IgA class and a neuropathy.  Included participants were not required to fulfil specific electrophysiological diagnostic criteria.  These researchers used standard Cochrane methodology to select studies, extract data and analyze results.  One trial author provided additional data and clarification.  These researchers identified 1 RCT, with 18 participants, that fulfilled the pre-determined inclusion criteria.  The trial compared PE to sham PE in participants with IgG or IgA paraproteinaemic neuropathy over a 3-week follow-up period.  They identified 4 other studies but these were not RCTs or quasi-RCTs.  The included RCT did not report the pre-defined primary outcome measure, change in disability 6 months after randomization.  The trial revealed a modest benefit of PE in the weakness component of the Neuropathy Disability Score (NDS, now the Neuropathy Impairment Score); the mean improvement with PE was 17 points (95 % CI: 5.2 to 28.8 points) versus 1 point (95 % CI: -7.7 to 9.7 points) in the sham PE group at 3 weeks' follow-up (mean difference (MD) 16.00; 95 % CI: 1.37 to 30.63, low quality evidence).  There was no statistically significant difference in the overall NDS (MD 18.00; 95 % CI: -2.03 to 38.03, low quality evidence), vibration thresholds or neurophysiological indices.  Adverse events were not reported.  The trial was at low risk of bias overall, although limitations of trial size and duration reduce the quality of the evidence in support of its conclusions.  The authors concluded that the evidence from RCTs for the treatment of IgG or IgA paraproteinaemic neuropathy is currently inadequate.  More RCTs of treatments are needed.  These should have adequate follow-up periods and contain larger numbers of participants, perhaps through multi-center collaboration, considering the relative infrequency of this condition.  Observational or open trial data provide limited support for the use of treatments such as PE, cyclophosphamide combined with prednisolone, intravenous immunoglobulin, and corticosteroids.  These interventions showed potential therapeutic promise but the potential benefits must be weighed against adverse effects.  Their optimal use and the long-term benefits need to be considered and validated with well-designed RCTs.

Nephrogenic Systemic Fibrosis

Ridel et al (2017) stated that PE is a non-selective apheresis technique that can be performed by filtration or centrifugation allowing rapid purification of high molecular weight pathogens.  An immunosuppressive treatment is generally associated to reduce the rebound effect of the purified substance.  Substitution solutes such as human albumin and macromolecules are needed to compensate for plasma extraction.  Compensation by viro-attenuated plasma is reserved solely for the treatment of thrombotic microangiopathies or when there is a risk of bleeding, because this product is very allergenic and expensive.  The treatment goal for a PE session should be between 1 and 1.5 times the patient's plasma volume estimated at 40 ml/kg body weight.  The anti-coagulation is best ensured by the citrate.  Complications of PE are quite rare according to the French hemapheresis registry.  The level of evidence of efficacy of PE in nephrology varies from one pathology to another.  Main indications of PE in nephrology are Goodpasture syndrome, anti-neutrophil cytoplasmic antibody vasculitis when plasma creatinine is greater than 500 μmol/L, and thrombotic microangiopathies.  During renal transplantation, PE may be proposed in the context of human leukocyte antigen (HLA) desensitization protocols or ABO-incompatible graft.  After renal transplantation, PE is indicated as part of the treatment of acute humoral rejection or recurrent focal segmental glomerulosclerosis on the graft; PE are also proposed in the management of cryoglobulinemia or polyarteritis nodosa.  Hemodialysis with membranes of very high permeability tends to replace PE for myeloma nephropathy.  The authors stated that benefit from PE has not been formally demonstrated for the treatment of severe lupus or APS.  They noted that there is no indication of PE in the treatment of scleroderma or nephrogenic systemic fibrosis.

Status Epilepticus

Zeiler et al (2016a) performed a scoping systematic review of the literature on the use of PP or (PE for refractory status epilepticus (RSE) in adults.  Articles from Medline, BIOSIS, Embase, Global Health, Healthstar, Scopus, Cochrane Library, the International Clinical Trials Registry Platform, clinicaltrials.gov (inception to May 2016), reference lists of relevant articles, and gray literature were searched.  The strength of evidence was adjudicated using both the Oxford and GRADE methodology by 2 independent reviewers.  A total of 22 original articles were identified; 27 adult patients were described in these articles, with a variety of autoimmune conditions leading to RSE.  Seizure response with the application of PE therapy occurred in 14 of the 27 patients (51.9 %), with 1 (3.7 %) and 13 (48.1 %) displaying partial response (PR) and complete response (CR), respectively.  Generalized RSE was the most likely seizure subtype to respond to PE therapy; 1 patient had recorded an adverse events (AEs) related to PE therapy.  The authors concluded that Oxford level 4, GRADE D evidence existed to suggest an uncertain response of adult autoimmune RSE to PE therapy.  Thus, they stated that routine application of PE therapy for adult autoimmune RSE cannot be recommended at this time.

Zeiler et al (2016b) performed a scoping systematic review of the literature on the use of PP or PE for RSE in children.  Articles from Medline, BIOSIS, Embase, Global Health, Healthstar, Scopus, Cochrane Library, the International Clinical Trials Registry Platform, clinicaltrials.gov (inception to May 2016), reference lists of relevant articles, and gray literature were searched.  The strength of evidence was adjudicated using both the Oxford and GRADE methodology by 2 independent reviewers.  A total of 22 original articles were identified, with 37 pediatric patients.  The mean age of the patients was 8.3 years (median of 8.5, range of 0.6 to 17).  Seizure response to PE therapy occurred in 9 of the 37 patients (24.3 %) included in the review, with 7 patients (18.9 %) displaying resolution of seizures and 2 patients (5.4 %) displaying a partial reduction in seizure volume; 28 of the 37 patients (75.7 %) had no response to PE therapy; no AEs were recorded.  The authors concluded that Oxford level 4, GRADE D evidence existed to suggest little to no benefit of PE in pediatric RSE.  They stated that routine application of PE for pediatric RSE cannot be recommended at this time.

Natalizumab-Associated Progressive Multifocal Leukoencephalopathy

In an UpToDate review of treatment of progressive multifocal leukoencephalopathy, Koralnick, et al (2017) stated that, "although benefit is uncertain as discussed below, we suggest a course of plasma exchange (eg, every other day for a total of five treatments) accompanied by oral mirtazapine (15 to 45 mg at bed time) for patients with natalizumab-associated PML." The rationale is to eliminate circulating natalizumab, which has a long duration of action that might delay immune reconstitution. The author noted, however, that the evidence is limited to small, retrospective observational studies, and benefit is unproven.

Dalhaus et al (2013) reported on the outcome of 15 patients with natalizumab-associated PML who were treated with plasmapheresis. The subjects were also treated with mirtazapine and mefloquine. Fourteen patients who developed  for all 15 patients, and 14 subjects who developed immune reconstitution inflammatory syndrome (IRIS) were treated with  high-dose glucocorticoids. The patients had a median natalizumab exposure of 34 months at PML diagnosis. Expanded Disability Status Scale (EDSS) and Karnofsky score in the year pre-PML, at PML-diagnosis (pre-immune reconstitution inflammatory syndrome (IRIS)) and post-PML were determined in 3-6 monthly intervals. The median follow-up of these 15 patients was 21.5 months. None of the 15 patients died. Three patients had a Karnofsky score of 80 or higher, nine patients between 50-70 and three patients of 40 or lower at latest examination. Eight of the 15 patients developed seizures during acute PML phase. Fifty percent of those patients were not seizure-free one year post PML, despite continuation of antiepileptic treatment. The median EDSS in the year pre-PML was 2.5, 4.5 at PML diagnosis, 6.5 post-IRIS and 5.5 at latest examination. CSF became virus-free in eight of the 15 patients after a median time of 4.5 months. In nine patients, disease reappeared after a median time of seven months from PML diagnosis.

Land and colleagues (2017) examined retrospectively the effects of plasmapheresis (PLEX) on the survival and clinical outcomes of patients with MS and natalizumab (NTZ)-associated progressive multifocal leukoencephalopathy (PML).  The medical literature was searched for the terms natalizumab and progressive multifocal leukoencephalopathy.  A total of 193 international and 34 Italian NTZ-PML cases were included.  Clinical outcome was determined by comparing the patients' clinical status at PML diagnosis with status after PML resolution.  The effects on survival and clinical outcome of PLEX, sex, age, country, pre-PML Expanded Disability Status Scale (EDSS) score, NTZ infusion number, prior immunosuppressant exposure, PML symptoms, PML lesion location at diagnosis, cerebrospinal fluid (CSF) JC virus status and copies, additional PML treatments and steroids, and PML immune reconstitution inflammatory syndrome (IRIS) development were investigated with both univariate and multivariate analyses.  A total of 219 NTZ-PML cases were analyzed, and 184 (84 %) underwent PLEX, which did not reduce the mortality risk or the likelihood of poor versus favorable outcomes.  Country was predictive of mortality and poor outcome, while PML-IRIS development was predictive of poor outcome.  The authors concluded that PLEX did not improve the survival or clinical outcomes of Italian or international patients with MS and NTZ-PML, suggesting that this treatment should be performed cautiously in the future.

In an editorial that accompanied the afore-mentioned study, Tyler and Vollmer (2017) stated that “The current study reminds us that benefits of PLEX in NTZ-PML are conjectural, not proven, and will remain so until real data on efficacy or lack thereof are available”.

Chronic Urticaria

Holm and colleagues (2018) reviewed the evidence for the use of non-biologic treatments in patients with chronic urticarial who are refractory to anti-histamines.  These investigators performed a systematic review of the literature using PubMed and Webofscience and identified studies that reported use of 1 or more of the non-biological, non-antihistamine therapeutic options for chronic urticaria.  The studies were evaluated based on study design, number of patients, effect of treatment and safety.  They identified 118 studies or case series with 13 different treatments (azathioprine, chloroquine, colchicine, cyclosporine, dapsone, IVIG, methotrexate, montelukast, mycophenolate mofetil, plasmapheresis, sulfasalazine, tranexamic acid and ultraviolet light (UV) A, UVB) totaling 1,682 patients.  There was a paucity of controlled trials for most of the treatments reviewed albeit the strongest evidence in favor of a beneficial effect in chronic urticaria was, apart from montelukast and cyclosporine, observed for UV therapy and dapsone followed by IVIG.  The authors concluded that the therapeutic options reviewed should be seen as potential alternatives in treatment-resistant chronic urticaria where guideline-based selections have failed.  Moreover, these researchers stated that larger controlled trials are needed to advance the level of evidence, possibly supporting some treatments' future recommendation in selected patients.

Hyperlipidemic Pancreatitis

In a systematic review, Adiamah and colleagues (2018) defined the epidemiology and pathophysiology of hyperlipidemic pancreatitis, established its association with clinical outcome, and defined management strategies.  The Cochrane, Embase and Medline databases were searched, limited to the past 10 years, for articles on hyperlipidemic pancreatitis.  All RCTs, observational studies as well as case series (with a minimum of 10 patients) on hyperlipidemic pancreatitis were included.  A total of 38 studies with 1,979 patients were included.  The median admission triglyceride concentration was 42.8 mmol/L (range of 13.6 to 108.6 mmol/L) [3,785 mg/dL (range of 1,205 to 9,612 mg/dL)].  Severe hypertriglyceridemia (greater than 1,000 mg/dL, 11.0 mmol/L) was present in 1.7 % of the adult population, and about 15 to 20 % of these developed hyperlipidemic acute pancreatitis.  Medical management of severe hyperlipidemia at onset of acute pancreatitis has not been investigated fully.  However, tight regulation of triglyceride concentration after presentation with acute pancreatitis was found to reduce the risk of recurrence.  Plasmapheresis reduced concentrations of triglycerides by up to 85 %, but this did not impact morbidity or mortality.  All studies included defined hyperlipidemia as a more severe form of pancreatitis.  The authors concluded that the available evidence suggested an increasing risk of acute pancreatitis in patients with hyperlipidemia and a more severe form of pancreatitis.  There is some evidence to suggest biochemical benefit of using novel techniques like plasmapheresis without the desired physiological benefit.  However, these researchers stated that there is a need for an international consensus on the management of hyperlipidemic pancreatitis; and more rigorous and methodologically robust studies are needed to guide such consensus guidelines.

Mantle Cell Lymphoma (Mantle Cell Leukemia)

Smith and colleagues (2004) reported on the case of a 76-year old man who presented with leukostasis syndrome, including oculodynia, blurred vision, and visual field defects, due to mantle cell lymphoma (MCL), prolymphocytoid variant, with marked leukocytosis, 1,227 x 10(9)/L (equivalent to 1,227,000/µL) .  He had splenomegaly but no lymphadenopathy or hepatomegaly.  The tumor cells were CD5+, CD19+, CD20+, FMC-7+, and kappa light chain restricted.  Immunohistochemistry showed expression of p53 and of cyclin D1.  Fluorescent in-situ hybridization (FISH) demonstrated t(11;14) with translocation between CYCLIN D1 and the immunoglobulin heavy-chain genes.  The patient received leukapheresis and aggressive chemotherapy, but the leukocyte count remained above 100 x 10(9)/L.  The patient's condition rapidly deteriorated with lymphomatous infiltration of his lungs and soft tissues, and he expired 6 months after diagnosis.  The authors concluded that while it is known that MCL may have a leukemic phase, the degree of leukocytosis in this case exceeded that previously reported in the literature and resulted in a clinical syndrome of leukostasis.

Nguyen and associates (2011) described a case of severe leukocytosis caused by leukemic MCL, complicated by leukostasis with myocardial infarction in which leukapheresis was used in the initial management.  A 73-year old man presented to the emergency department because of fatigue and thoracic pain.  Blood count revealed 630 × 10(9)/L WBC (equivalent to 630,000/µL ; white blood cells).  The electrocardiogram showed ST-elevation with an increase of troponin and creatinine kinase.  The diagnosis was ST-elevation myocardial infarction (STEMI) induced and complicated by leukostasis.  Immuno-phenotyping, morphology, cytogenetic and FISH analysis revealed the diagnosis of a blastoid variant of MCL.  To remove leukocytes rapidly, leukapheresis was performed in the intensive care unit.  Based on the differential blood count with 95 % blasts, which were assigned to the lymphocyte population by the automatic hematology analyzer, leukapheresis procedures were then performed with the mononuclear cell standard program on the Spectra cell separator.  The patient was treated with daily leukapheresis for 3 days.  The WBC count decreased to 174 × 10(9)/L after the 3rd leukapheresis, with a 72 % reduction.  After the second apheresis, treatment with vincristine, cyclophosphamide, and prednisolone was started.  The patient fully recovered in the further course of the treatment.  The authors concluded that to the best of their knowledge, this was the first report on blastoid MCL with leukostasis associated with a STEMI that was successfully treated by leukapheresis.  Effective harvest of circulating lymphoma cells by leukapheresis requires adaptation of instrument settings based on the results of the differential blood count prior to apheresis.

Smith and associates (2011) reported on the case of a 72-year old man who was admitted with hypoxemic respiratory distress.  Given a WBC count of 600 × 10(9)/L (equivalent to 600,000/µL) and symptoms of leukostasis, emergency leukapheresis was initiated.  The WBC count immediately after the first leukapheresis was paradoxically increased to over 700 × 10(9)/L.  Peripheral blood smear findings showed morphologically immature mononuclear cells and numerous circulating mitotic figures.  Initial flow cytometry results showed a lambda light chain-restricted B lymphoid population positive for CD20, CD19, CD5, and FMC-7, and negative for TdT, CD10, CD23, CD34, CD117, and myeloid markers, suggesting classification as a blastoid variant of MCL in a leukemic phase.  Subsequent testing using DNA fluorescence in-situ hybridization (FISH) was positive for t(11;14), confirming the diagnosis of MCL.  Although MCL occasionally transforms or can even present as leukemia (leukocytes greater than 40 × 10(9)/L), it is rare for it to present with such profound leukocytosis and an overwhelming number of pleomorphic/blastoid forms.  Although morphology suggested acute lymphoblastic leukemia (ALL), a more specific diagnosis of blastoid variant MCL was obtained in 12 hours by applying complementary techniques of flow cytometry and rapid cytogenetics.

Ganzel and colleagues (2012) noted that hyper-leukocytosis, arbitrarily defined in acute leukemia as a WBC count greater than 100,000/µL, often is associated with increased morbidity and mortality in patients with leukemic processes.  It can induce leukostasis, tumor lysis syndrome and disseminated intravascular coagulopathy and has significant prognostic implications with or without one of these clinical complications.  The main sites that tend to be injured from the obstructions are the CNS and lungs.  Despite characteristic clinical presentations, the diagnosis of leukostasis is rarely made with high confidence.  The primary objective of the management of hyper-leukocytosis and/or leukostasis is to reduce the WBC count before starting induction chemotherapy; cytoreduction can be achieved by either leukapheresis and/or hyroxyurea.

Kwan and co-workers (2016) noted that MCL is an aggressive malignant B-cell disorder that often presents with a leukemic picture.  Circulating lymphoma cell morphology may vary from small round mature-appearing lymphocytes resembling the lymphocytes of chronic lymphocytic leukemia (CLL) to large prolymphocytoid or blastoid cells.  Rare reports of hyper-leukocytosis with leukostasis, treated with leukocytapheresis, had been described in patients with prolymphocytoid or blastoid morphology.  These investigators reported on the case of an 88-year old woman with MCL, hyper-leukocytosis (WBC greater than 400,000/µL) with severe respiratory compromise but without interstitial or alveolar infiltrates on radiograph or computerized tomography of the chest.  She was afebrile and had no central nervous system signs.  Circulating lymphoma cell morphology was predominantly of the small lymphocyte type.  A 2-whole-blood-volume leukocytapheresis reduced her WBC from 465,000 to 221,000/µL in 150 mins.  Her respiratory rate decreased from 28/min to 18/min and her arterial oxygen saturation (SpO2 ) rose from 91 % to 97 % on 6 L/min of oxygen by nasal cannula.  Severe breathlessness before the procedure abated completely by the end of the procedure.  The authors concluded that respiratory compromise may occur in MCL with hyperleukocytosis with a mature lymphoma cell phenotype, even without a clear picture of leukostasis.  Although the ultimate survival of the patient depended on treatment with chemotherapy, leukocytapheresis for alleviation of symptoms may be warranted and should be considered.  Respiratory status and response to leukocytapheresis should be documented with physiological measurements.

Hemoglobin Buenos Aires

de Weinstein and colleagues (1973) reported that a new unstable hemoglobin, Hb Buenos Aires,β85 (Fl) phenylalanine→serine has been found in an Argentinian family; 4 members were found to be heterozygous for this hemoglobin, and all suffered from a compensated hemolytic anemia.  This hemoglobin is the 5th example of an unstable variant resulting from the substitution of one of the phenylalanine residues in Hb A and underlines the importance of this large hydrophobic amino acid in maintaining the internal structure and stability of the molecule.  

Larson and associates (1997) stated that hemoglobin (Hb) Bryn Mawr is an unstable Hb variant resulting in congenital hemolytic anemia.  This variant Hb also has an increased affinity for oxygen.  The peri-operative transfusion management of this disorder was described, and the first genomic analysis of this Hb variant was given.  An 11-year old boy, heterozygous for Hb Bryn Mawr, was referred for cholecystectomy.  Sequence analysis of genomic DNA confirmed that the patients was heterozygous for a T-->C transition in the codon for amino acid 85, causing a substitution of serine for phenylalanine in the beta-globin chain.  On the basis of whole-blood O2 dissociation studies, projected tissue O2 delivery would have been suboptimal during general anesthesia; therefore, a partial red cell exchange transfusion was performed to lower variant Hb and prevent tissue hypoxia during surgery.  The red cell mass to be exchanged (50 %) was determined from the calculated increase in O2 delivery capacity required to maintain an O2 extraction of 4 to 5 ml of O2 per dL of whole blood.  The p50 of whole blood from the patients immediately after the exchange transfusion was 16.0 Torr.  At the time of surgery, the p50 was normal (25.9 Torr).  The patient's whole blood 2,3 DPG levels were 4.70 mmol per ml of red cells (before transfusion) (normal range = 4.8 +/- 0.3 mmol/ml red cells), 4.07 mmol per ml of red cells (immediately after transfusion), and 4.55 mmol per ml of red cells (48 hours after transfusion).  The authors concluded that this patient with Hb Bryn Mawr was prepared for surgery with a partial exchange transfusion to prevent tissue hypoxia during anesthesia.  Decreased 2,3 DPG levels immediately after transfusion resulted in increased O2 affinity of whole blood; however, 48 hours after exchange transfusion, a normal p50 (due to both removal of variant Hb and regeneration of 2,3, DPG) was observed.  Partial exchange transfusion was useful in the pre-operative management of patients with Hb variants characterized by increased O2 affinity.

Ando and co-workers (2004) reported the case of a 20-year old man who had been under observation for 18 years because of unstable hemoglobinemia, Hb Buenos Aires, Bryn Mawr (beta-globin, Phe85Ser).  At the age of 19 years, he was hospitalized because of fever and hemolytic crisis, and the symptoms resolved after infusion of antibiotics.  Nucleotide sequencing of the beta-globin gene confirmed that the patient was heterozygous for the mutation.  The patient's erythrocytes showed an increased affinity for oxygen and a prolonged glycerol lysis time.  The authors reviewed a previously reported single family and 5 other cases, and discussed the clinical significance of splenectomy and plasma-derived haptoglobin. 

Furthermore, an UpToDate review on “Unstable hemoglobin variants” (Steinberg, 2018) does not mention apheresis as a therapeutic option.

Urticarial Vasculitis

Kolkhir and colleagues (2019) noted that urticarial vasculitis (UV) is a difficult-to-treat condition characterized by long-lasting urticarial rashes and histopathologic findings of leukocytoclastic vasculitis.   Treatment is dictated by the severity of skin and systemic involvement and the underlying systemic disease.  In a systematic review, these investigators examined the efficacy of current UV therapeutic options.  They searched for relevant studies in 7 databases, including Medline, Scopus, and Web of Science.  A total of 261 eligible studies and 789 unique patients with UV were included in the systematic review.  Most patients with UV were adult women with chronic (greater than or equal to 6 weeks) and systemic disease.  These researchers stated that UV is mostly idiopathic but could be associated with drugs, malignancy, autoimmunity, and infections.  It usually resolves with their withdrawal or cure.  Corticosteroids are effective for the treatment of skin symptoms in more than 80 % of patients with UV.  However, their long-term administration could result in potentially serious adverse effects.  The addition of immunomodulatory or immunosuppressive agents often allows corticosteroid tapering and improves the efficacy of therapy.  Biologicals, including omalizumab, as well as corticosteroids, cyclophosphamide, dapsone, mycophenolate mofetil, plasmapheresis (PP), colchicine, hydroxychloroquine, IVIG, nonsteroidal anti-inflammatory drugs (NSAIDs), and cyclosporine, could be effective for both skin and systemic symptoms in patients with UV.  H1-antihistamines, montelukast, danazol, H2-antihistamines, pentoxifylline, doxepin, and tranexamic acid are not effective in most patients with UV.  The authors concluded that as of yet, no drugs have been approved for UV, and management recommendations are based mostly on case reports and retrospective studies.  These investigators stated that prospective studies examining the effects of treatment on the signs and symptoms of UV are needed.

Heparin-Induced Thrombocytopenia

Maffei and colleagues (2020) noted that anti-coagulation with unfractionated heparin (UFH) is vital to reduce the risk of thromboembolic events during cardio-pulmonary bypass and left ventricular assist device (LVAD) placement.  However, patients with heparin-induced thrombocytopenia (HIT) are at risk of developing immune-mediated thrombotic events.  These researchers described 2 patients with HIT confirmed via serotonin release assay who were successfully treated with plasmapheresis exchange before LVAD placement.

An UpToDate review on “Management of heparin-induced thrombocytopenia” (Coutre and Crowther, 2020) states that “Other approaches, including fibrinogen-depleting agents (e.g., ancrod), thrombolysis, plasmapheresis, or dextran, are either not effective or are unproven for the routine initial treatment of HIT”.

An UpToDate review on “Management of heparin-induced thrombocytopenia (HIT) during cardiac or vascular surgery” (Ortel and Welsby, 2020) states that “Patients with active HIT (or a diagnosis of HIT within approximately the preceding 3 months) are in an extremely prothrombotic state because they are likely to have circulating anti-PF4/heparin antibodies that can activate platelets and can cause life-threatening venous and/or arterial thrombosis.  We make every possible attempt to avoid use of heparin or delay surgery in these individuals.  Options for those in whom surgery cannot be delayed are discussed above, including use of a non-heparin agent, plasmapheresis, administration of intravenous immune globulin (IVIG), or administration of epoprostenol.  Data are extremely limited, and decisions among these options are individualized”.

Guidelines on heparin-induced thrombocytopenia from the American Society of Hematology (ASH) (Cuker et al, 2018) stated that In patients with subacute HIT B or remote HIT who require cardiovascular surgery, the ASH guideline panel suggests intraoperative anticoagulation with heparin rather than treatment with a non-heparin anticoagulant, plasma exchange and heparin, or heparin combined with an antiplatelet agent. (Subacute HIT B is the interval after the functional assay becomes negative but before the immunoassay becomes negative).  In patients with acute HIT or subacute HIT A who cannot delay cardiovascular surgery, the ASH guideline panel suggests one of the following: intraoperative anticoagulation with bivalirudin, intraoperative heparin after treatment with preoperative and/or intraoperative plasma exchange, or intraoperative heparin in combination with a potent antiplatelet agent (e.g., prostacyclin analog or tirofiban).  (Subacute HIT A is the phase following platelet count recovery but before the functional assay becomes negative).

Neuroinflammation Due to Myelin Oligodendrocyte Glycoprotein (MOG) Antibody Disease

Wynford-Thomas et al (2019) stated that myelin oligodendrocyte glycoprotein (MOG) antibody disease (MOG-AD) is now recognized as a nosological entity with specific clinical and para-clinical features to aid early diagnosis.  Although no age group is exempt, median age of onset is within the 4th decade of life, with optic neuritis being the most frequent presenting phenotype.  Disease course can be either monophasic or relapsing, with subsequent relapses most commonly involving the optic nerve.  Residual disability develops in 50 to 80 % of patients, with transverse myelitis at onset being the most significant predictor of long-term outcome.  Recent advances in MOG antibody testing offer improved sensitivity and specificity.  To avoid misdiagnosis, MOG antibody testing should be undertaken in selected cases presenting clinical and para-clinical features that are felt to be in keeping with MOG-AD, using a validated cell-based assay.  MRI characteristics can help in differentiating MOG-AD from other neuro-inflammatory disorders, including multiple sclerosis (MS) and neuromyelitis optica (NMO).  Cerebrospinal fluid (CSF) oligoclonal bands are uncommon.  Randomized control trials are limited, but observational open-label experience suggested a role for high-dose steroids and plasma exchange (PE) in the treatment of acute attacks, and for immunosuppressive therapies, such as steroids, oral immunosuppressants and rituximab as maintenance treatment.  Plasma exchange (regime varying from 3 to 5 cycles) is more commonly used as a 2nd-line treatment following steroid resistance and can result in around 40 % of cases of MOG antibody ON and/or myelitis having a complete or almost complete recovery.

Tajfirouz e al (2019) noted that antibodies against MOG are associated with a unique acquired central nervous system (CNS) demyelinating disease-termed MOG-AD, which has a variety of clinical manifestations, including optic neuritis, transverse myelitis, acute disseminating encephalomyelitis, and brainstem encephalitis.  These investigators examined the current knowledge of the clinical characteristics, neuroimaging, treatments, and outcomes of MOG-AD, with a focus on optic neuritis.  The recent development of a reproducible, live cell-based assay for MOG-IgG, has improved the ability to identify and study this disease.  Based on contemporary studies, it has become increasingly evident that MOG-AD is distinct from MS and aquaporin-4-positive NMO spectrum disorder with different clinical features and treatment outcomes.  There is now sufficient evidence to separate MOG-AD from other inflammatory CNS demyelinating disorders, which will allow focused research on understanding the pathophysiology of the disease.  The authors stated that prospective treatment trials are needed to determine the best course of treatment, and until then, treatment plans must be individualized to the clinical manifestations and severity of disease.

Schizophrenia

Cox and colleagues (2020) stated that increasing evidence suggested that circulating factors and immune dysfunction may contribute to the pathogenesis of schizophrenia.  In particular, pro-inflammatory cytokines, complement and auto-antibodies against CNS epitopes have recently been associated with psychosis.  Related concepts in past decades led to several clinical trials of dialysis and PE as treatments for schizophrenia.  These trials may have relevance for the current understanding of schizophrenia.  These researchers examined if dialysis or PE is beneficial in treating schizophrenia.  They carried out a systematic search in major electronic databases for high-quality studies (randomized, double-blinded trials with sham controls) applying either hemodialysis or PE as an intervention in patients with schizophrenia, published in English from the start of records until September 2018.  A total of 9 studies met inclusion criteria, reporting on 105 patients who received either sham or active intervention; 1 out of 8 studies reported a beneficial effect of hemodialysis on schizophrenia, 1 a detrimental effect and 6 no effect.  The 1 trial of PE found it to be ineffective; AEs were reported in 23 % of patients.  Studies were at unclear or high risk of bias.  The authors concluded that it is unlikely that hemodialysis is a beneficial treatment in schizophrenia, although the studies were of small size and could not consider potential subgroups.  Plasmapheresis was only addressed by 1 study and warrants further investigation as a treatment modality in schizophrenia.

Secondary Polycythemia

Kessler (2004) noted that apheresis is in blood components separators used to remove abundant or pathological blood components or to replace them with healthy ones.  Erythrocytapheresis is an up-to-date, efficient and selective alternative of venepuncture.  In the author’s country (the Czech Republic), it is used especially for treatment of abundant erythrocytes in polycythemia vera (PV) and secondary polyglobulias where its correct use leads both to significant symptomatic relief and erosion of pathogenetic chain and to a reduction of over-production of erythrocytes.

Evers et al (2014) noted that recently, therapeutic erythrocytapheresis (TE) was suggested to be more efficient in depletion of red blood cells (RBC) compared to manual phlebotomy in the treatment of hereditary hemochromatosis (HH), PV, and secondary erythrocytosis (SE).  The efficiency rate (ER) of TE, that is, the increase in RBC depletion achieved with 1 TE cycle compared to 1 phlebotomy procedure, can be calculated based on estimated blood volume (BV), pre-procedural hematocrit (Hct(B)), and delta-hematocrit (ΔHct).  In a retrospective evaluation of 843 TE procedures (in 45 HH, 33 PV, and 40 SE patients) the mean ER was 1.86 ± 0.62 with the highest rates achieved in HH patients.  An ER of 1.5 was not reached in 37.9 % of all procedures mainly concerning patients with a BV below 4,500 ml.  In 12 newly diagnosed homozygous HH patients, the induction phase duration was medially 38.4 weeks (medially 10.5 procedures).  During the maintenance treatment of HH, PV, and SE, the interval between TE procedures was medially 13.4 weeks.  This mathematical model can help select the proper treatment modality for the individual patient.  Especially for patients with a large BV and high achievable ΔHct, TE appeared to be more efficient than manual phlebotomy in RBC depletion; thus, potentially reducing the numbers of procedures and expanding the inter-procedural time period for HH, PV, and SE.

Salinas et al (2020) stated that TE is a more efficient strategy compared to phlebotomy to deplete levels of Hct in primary and secondary erythrocytosis.  These investigators analyzed response rate and safety profile of TE in PV and SE.  They carried out a retrospective review of all patients with PV or SE treated with TE, due to phlebotomy failure, or co-morbidities that prevented changes of blood volume.  A total of 217 TE sessions (48 PV and 79 SE) corresponding to 20 patients (12 ES and 8 PV) were performed.  Response were achieved in 87.5 % of PV patients and in 50 % of SE patients.  Adverse effects related to TE performance occurred in 7.08 %.  The authors concluded that despite the small sample size and the heterogeneous nature of the patients included, they could postulate that TE was a secure strategy that could achieve Hct depletion in a shorter time than phlebotomy, specifically in PV patients and in selected cases of SE with expected hemodynamic intolerance to phlebotomies or in patients who fail to respond to phlebotomies.

In a recent review on “Investigation and management of erythrocytosis”, Mithoowani et al (2020) stated that “Secondary erythrocytosis, which is more common than PV, has a broad differential diagnosis that includes hypoxic lung disease, cyanotic congenital heart disease, medications (e.g., testosterone) and erythropoietin-producing malignant disorders … Treatment of secondary erythrocytosis should be directed at the underlying cause, and phlebotomy is not routinely recommended”.  Plasmapheresis, plasma exchange, or therapeutic apheresis is not mentioned as a management /therapeutic option.

Furthermore, an UpToDate review on “Prognosis and treatment of polycythemia vera” (Tefferi, 2021) does not mention apheresis / plasmapheresis / plasma exchange as a management / therapeutic option.

Snakebite-Associated Thrombotic Microangiopathy

Noutsos and colleagues (2020) noted that snakebite is a neglected tropical disease with significant morbidity and mortality.  Thrombotic microangiopathy (TMA) is an important but poorly understood complication of snakebite associated with acute kidney injury (AKI).  Numerous treatments have been tried based on limited evidence.  These researchers carried out a systematic review of TMA following snakebite using a pre-determined case definition of blood film red cell schistocytes or histologically diagnosed TMA.  The search strategy included major electronic databases and grey literature.  They presented a descriptive synthesis for the outcomes of AKI, dialysis free survival (DFS), other end-organ damage, overall survival (OS), and interventions with anti-venom and TPE.  A total of 72 studies reporting 351 cases were included, predominantly small observational studies.  Heterogeneity for study selection, design, reporting and outcomes were observed.  The commonest envenoming species were hump-nosed vipers (Hypnale spp.), Russell's viper (Daboia russelii) and Australian brown snakes (Pseudechis spp.).  The prevalence of TMA was at least 5.4 % in proven and probable Hypnale bites, and 10 to 15 % of Australian elapid envenomings; AKI occurred in 94 % (293/312) of TMA cases, excluding case reports.  The majority of cases with AKI required dialysis.  Included prospective and retrospective cohort studies reporting interventions and renal outcomes showed no evidence for benefit from anti-venom or TPE with respect to DFS in dialysis-dependent AKI.  The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) assessment for quality of accumulated evidence for interventions was low.  The major complication of TMA following snakebite was AKI, which improved in most cases.  The authors concluded that they found no evidence to support benefit from anti-venom in snakebite-associated TMA; however, anti-venom remains the standard of care for snake envenoming.  There was no evidence for benefit of TPE in snakebite-associated TMA; thus, TPE cannot be recommended.  The quality of accumulated evidence was low, highlighting a need for large, prospective, good quality studies.

Granulocyte and Monocyte Apheresis for the Induction and Maintenance of Clinical Remission in Ulcerative Colitis

Kiss and colleagues (2021) noted that the objective of treatment in ulcerative colitis (UC) is to induce and maintain remission.  The addition of granulocyte and monocyte apheresis (GMA) to conventional therapy may be a promising therapeutic alternative.  In a systematic review and meta-analysis, these researchers examined the safety and effectiveness of GMA as an adjunctive therapy.  They searched 4 databases (Medline, Embase, Web of Science and Cochrane Central Register of Controlled Trials) for RCTs or minimized controlled trials that discussed the impact of additional GMA therapy on clinical remission induction and clinical remission maintenance compared with conventional therapy alone.  Primary outcomes were clinical remission induction and maintenance, secondary outcomes were AEs and steroid-sparing effect; odds ratios (ORs) with 95 % CIs were calculated.  Trial Sequential Analyses were performed to adjusts for the risk of random errors in meta-analyses.  A total of 11 studies were eligible for meta-analysis.  GMA was clearly demonstrated to induce and maintain clinical remission more effectively than conventional therapy alone (598 patients: OR: 1.93, 95% CI: 1.28 to 2.91, p = 0.002, I2 = 0.0 % for induction; 71 patients: OR: 8.34, 95 % CI: 2.64 to 26.32, p < 0.001, I2 = 0.0 % for maintenance).  There was no statistically significant difference in the number of AEs (OR: 0.27, 95 % CI: 0.05 to 1.50, p = 0.135, I2 = 84.2 %).  The authors concluded that GMA appeared to be more effective as an adjunctive treatment in inducing and maintaining remission in patients with UC than conventional therapy alone.  Moreover, these researchers stated that these findings were limited by the relatively low number of patients and the heterogenous reporting of AEs.  They stated that further studies are needed to select patients who may benefit the most from GMA therapy.  Nevertheless, more RCTs are needed to justify its role in remission induction.  There is currently evidence available regarding induction and maintenance of clinical remission; however, the role of GMA concerning endoscopic and histological remission is currently unclear.  These investigators stated that If GMA is proven to be safe and effective, cost-effectiveness studies will also be worthwhile in the future.

Therapeutic Plasma Exchange (TPE) for the Treatment of Coronavirus Disease 2019 (COVID-19)

In a pilot study, Faqihi et al (2020) examined the effect of TPE on life-threatening coronavirus disease 2019 (COVID-19) presenting as acute respiratory distress syndrome (ARDS) plus multi-organ failure (MOF) and cytokine release syndrome (CRS).  These researchers prospectively enrolled 10 consecutive adult intensive care unit (ICU) subjects [7 men; median age of 51 years; inter-quartile range (IQR): 45.1 to 55.9 with life-threatening COVID-19 infection).  All had ARDS [PaO2/FiO2 ratio: 110 (IQR): 95.5 to 135.5], septic shock, CRS and deteriorated within 24 hours of ICU admission despite fluid resuscitation, antibiotics, hydroxychloroquine, ARDS-net and prone position mechanical ventilation.  All received 5 to 7 TPE sessions (dosed as 1.0 to 1.5 plasma volumes).  All of the following significantly normalized (p < 0.05) following the TPE completion, when compared to baseline: Sequential Organ Function Assessment score, PaO2/FiO2 ratio, levels of lymphocytes, total bilirubin, lactate dehydrogenase, ferritin, C-reactive protein (CRP) and interleukin-6 (IL-6).  No adverse effects from TPE were observed.  Acute kidney injury (AKI) and pulmonary embolism (PE) were observed in 10 % and 20 % of patients, respectively.  The duration of mechanical ventilation was 9 (IQR: 7 to 12) days, the ICU length of stay (LOS) was 15 (IQR: 13.2 to 19.6) days and the mortality on day-28 was 10 %.  The authors concluded that TPE demonstrated a potential survival benefit, and low complication risk in life-threatening COVID-19, albeit in a small pilot study.

Krzych and associates (2021) noted that since the COVID-19 pandemic outbreak, multiple promising treatment modalities have been tested.  However, only several of them were proven to be effective; TPE has been recently discussed as a possible supportive treatment for severe cases.  These investigators examined a possible role of TPE in severe COVID-19 by means of a structured systematic search strategy to retrieve all relevant publications in the field.  They screened in PubMed, Embase, Web of Science, Cochrane Library and clinicaltrials.gov for data published until the June 4, 2021.  These researchers identified 18 studies, enrolling 384 patients, 220 of whom received TPE.  The number of TPE sessions ranged from 1 to 9 and the type of replacement fluid varied markedly between studies (fresh frozen plasma or 5 % albumin solution, or convalescent plasma).  Biochemical improvement was observed in majority of studies as far as CRP, IL-6, ferritin, lactate dehydrogenase (LDH), D-dimer concentrations and lymphocyte count are concerned.  The improvement at a laboratory level was associated with enhancement of respiratory function.  Adverse effects were limited to five episodes of transient hypotension and 1 femoral artery puncture and thrombophlebitis.  The authors concluded that although the effect of TPE on mortality remains unclarified, the procedure appeared to improve various secondary endpoints such as partial pressure of arterial oxygen to fractional inspired oxygen (PaO2/FiO2) ratio or biomarkers of inflammation.

The authors stated that this study had several drawbacks.  First, a limited number of trials have been completed so far.  Due to methodological heterogeneity between publications and subsequent risk of bias, these investigators failed to prepare a meta-analysis.  Case studies usually described positive data; thus, strong publication bias exists; and the afore-mentioned studies should be interpreted with caution.  Only 1 RCT has been performed.  The included studies suffer from lack of adequate reporting, namely, day of mortality assessment, side effects or median time from symptoms to TPE initiation.  Furthermore, the procedure in COVID-19 has not been standardized yet.  Clinical indications, time of commencement of TPE, number of sessions, time gaps between them and the type of replacement fluid varied between studies.  Noteworthily, the type of a replacement fluid is debatable.  Albumin solutions may cause significant and unpredictable disturbances of blood coagulation due to loss of pro- as well as anti-coagulant factors.  One may then expect that convalescent plasma should be the 1st choice of treatment; however, recent data were not so convincing.  Moreover, plasma transfusion may have serious side effects, including transfusion-related immunomodulation and transfusion-related lung injury, which are of particular importance in COVID-19 patients with respiratory failure.  Moreover, the time at which various biomarkers’ concentrations were measured was different between the studies; therefore, reliable assessment of TPE effectiveness needs the unification of procedure-related issues.  In the future, this should be clarified.  Lastly, TPE is never used as the sole therapeutic option; it is only a part of the complex patient-oriented multi-factorial therapy.

Mousavi-Roknabadi and co-workers (2021) noted that several studies have suggested that the PE and hemoperfusion (HP) played a cardinal role in the treatment of severe COVID-19 cases by diminishing the cytokine storm.  In a systematic review, these researchers examined the effects of PE and HP on cytokine storms in patients with severe COVID-19 through a systematic scoping review.  A total of 4 electronic databases (Medline [accessed from PubMed], Scopus, Science Direct, and Cochrane library) were searched systematically on February 2, 2021, using MESH terms and related keywords in the English language.  Considering the titles and abstracts, unrelated studies were excluded.  The full texts of the remained studies were evaluated by authors, independently.  Then, their findings were assessed and reported.  A total of 755 articles were obtained within the first step of searching, and 518 remained after removing the duplications.  Through the title and abstract screening, 438 were removed.  Of the rest, 59 papers were excluded.  Finally, after reading the full text of the remained articles, 21 were included in data extraction.  Most of the previously reported evidence were case reports and case series.  Findings were summarized in 2 categories.  The 1st category included 9 studies regarding HP and continuous renal replacement therapy, and the 2nd category included 12 studies regarding PE.  The results revealed that HP and PE within the cytokine storm phase would be beneficial with a high probability in the treatment of severely ill COVID-19 patients.  The authors concluded that due to the insufficient high‐quality studies, it is recommended that more controlled clinical trials be carried out, and a specific therapeutic protocol, as well as its advantages and disadvantages, be defined.

Lu and colleagues (2021) stated that the potential benefit of TPE as adjunctive therapy for COVID‐19 by controlling cytokine‐mediated inflammation remains theoretical.  The causal relationship between CRS and the development and progression of ARDS, MOF, and septic shock still remains to be proven.  TPE not only removes pro‐inflammatory cytokines, but also anti‐inflammatory mediators and host defense factors.  It is unclear if TPE is capable of curbing CRS while maintaining an adequate anti‐viral immune response.  There is no published data in support of the claim that TPE can diminish SARS‐CoV‐2 viral load.  Given the novel nature of this virus, clinical studies are limited; moreover, studies examining the role of TPE in other viral illnesses are also inconclusive.  TPE and adsorption devices compatible with TPE have not been appropriately and adequately studied as adjunctive therapy for COVID‐19.  The LEOSS (Lean European Open Survey on SARS‐CoV‐2 Infected Patients) registry is an open, international, anonymous registry covering all aspects of COVID‐19 including treatment using TPE.  As of August 2020, the trial registry site clinicaltrials.gov listed almost 3,000 COVID‐19 trials, nearly 10 studying the use of TPE or extracorporeal methods in COVID‐19.  With these clinical trials underway, new evidence may come to light in the future that will provide stronger recommendations.

Wardhani et al (2021) noted that cytokine storm has been widely known to contribute to the development of the critical condition in patients with COVID-19, and studies had been carried out to examine the potential aspect of cytokine storm elimination by performing TPE.  However, contradictory findings were observed.  In a meta-analysis, these researchers examined the association between TPE and the reduction of mortality of critically ill COVID-19 patients.  They collected data from PubMed, Scopus, and Web of Science.  Data on the mortality rate of critically ill COVID-19 patients treated with TPE plus standard of care and that of patients treated with SOC alone were analyzed using a Z test.  These investigators included a total of 4 studies evaluating the association between TPE and the risk of mortality among critically ill COVID-19 patients.  They noted that their findings suggested that critically ill COVID-19 patients treated with TPE had lower risk of mortality compared to those without TPE treatment.  The authors concluded that this meta-analysis has identified the potential benefits of TPE in reducing the risk of mortality among critically ill COVID-19 patients.

The authors stated that since this was the initial evidence on the potential effectiveness of TPE for the management of COVID-19, several drawbacks should be addressed.  First, they did not include any potential confounding factors such as co-morbidity, the levels of pro-inflammatory cytokines, and onset of disease course to describe the association between TPE and the risk of mortality rate.  Second, a limited number of investigations on the use of TPE in COVID-19 management resulted in this study including only a limited number of articles; thus, further investigation involving a larger sample size is needed.  Third, the clinical setting on the use of TPE might differ among studies; thus, this variation might also govern the potency of bias.  Fourth, among the included studies, these researchers obtained only 1 RCT and 3 observational studies.  They stated that further meta-analyses involving only RCT studies might provide better levels of evidence.

The U.S. Food and Drug Administration (FDA, 2020) issued an emergency use authorization for an apheresis system to treat patients 18 years of age or older with confirmed Coronavirus Disease 2019 (COVID-19) admitted to the intensive care unit (ICU) with confirmed or imminent respiratory failure. The FDA issued this emergency use authorization to Terumo BCT Inc. and Marker Therapeutics AG for their Spectra Optia Apheresis System and Depuro D2000 Adsorption Cartridge devices.

TPE followed by Convalescent Plasma Transfusion for the Treatment of COVID-19

Novacescu and colleagues (2022) stated that TPE has been proposed as a rescue therapy in critically ill COVID-19 patients.  In a prospective, single center, non-randomized controlled trial, these researchers examined if combining TPE with convalescent plasma (CVP) transfusion early in the intensive care unit (ICU) stay would improve survival among this heterogeneous population.  The primary endpoint was survival at 30 days.  Secondary endpoints included assessing the evolution of biomarkers, such as the PaO2/FiO2 ratio, CRP, LDH and ferritin levels at the 7-day follow-up.  This study was carried out in an 8-bed COVID-19 ICU and included patients with severe COVID-19 pneumonia requiring intensive care treatment.  A total of 19 patients were treated by performing TPE followed by CVP transfusion, in addition to SOC, while for another 19 patients, only SOC according to hospital protocols was used.  TPE was initiated during the first 24 hours after ICU admission, followed immediately by transfusion of CVP.  Survival at 30 days was 47.37 % in the TPE CVP group and 26.32 % in the control group (p = 0.002).  Patients in the TPE CVP group also showed better oxygenation and a reduction in inflammation, with decreased CRP, LDH and ferritin levels compared with those in the control group.  The authors concluded that the findings of this study indicated that early initiation of TPE followed by CVP transfusion may be a valid rescue therapy in severe and critically ill COVID-19 patients, with a statistically significant survival benefit, improved oxygenation and a reduction in inflammatory markers.  Moreover, these researchers stated that more research consisting of large RCTs should be carried out to further examine this innovative treatment.  These investigators stated that drawbacks of the study included the small number of patients enrolled (n = 19 in each group), the non-randomized nature of the study and the low neutralizing antibody titer ratio of the CVP (1:80 to 1:160).  In addition, the use of corticosteroids and different anti-viral agents may have influenced the outcome.

Hypertriglyceridemia-Induced Acute Pancreatitis

In a prospective, single-center, pilot study, Lei et al (2022) examined the safety and effectiveness of double filtration plasmapheresis (DFPP) in severe hypertriglyceridemia (sHTG) patients (TG greater than 1,000 mg/dL).  Peripheral venous access of upper extremities was used for DFPP.  Blood flow rate was 100 to 120 ml/min, and plasma separation rate was 800 to 1,000 ml/hour.  Plasma volume to treat in each case was calculated with the Kaplan formula.  Anti-coagulation was achieved by low molecular weight heparin (LMWH).  Treatment objective was triglyceride level decreased to normal (less than 1.7 mmol/L).  Epidemiological data, lipid, hematological parameters as well as side effects were examined before and after DFPP.  A total of 7 patients (6 males and 1 female) were consecutively enrolled to this trial.  There was diabetes mellitus type 2 (DMT2) in 4 patients and obesity-associated nephropathy in 1 patient.  The mean age was 42.5 years.  The average TG level before plasmapheresis was 17.41 mmol/L (range of 10.93 to 26.33 mmol/L).  After 1 session, the levels of triglyceride, total cholesterol, LDL-c, HDL-c decreased significantly by 58.3 %, 43.2 %, 41.9 %, and 20.7 %, respectively.  The mean number of treatment sessions was 1.5 (range of 1 to 3); DFPP was well-tolerated.  Except for transient decrease of albumin, globulin and fibrinogen, liver and renal functions, hematological parameters did not change significantly.  The authors concluded that according to their experience, DFPP may be used safely and effectively in sHTG patients at risk of acute coronary events and AP; however, further RCTs are needed to examine the long-term effect.

Yan et al (2023) noted that the treatment of acute pancreatitis (AP) induced by HTG remains controversial with regard to plasmapheresis versus conventional treatment.  In a systematic review, these investigators examined relevant studies to evaluate the effectiveness of plasmapheresis in the management of HTG-induced AP.  They reviewed studies that compared plasmapheresis with conventional treatment for HTG-induced AP using 3 databases: PubMed, Embase, and Cochrane Library, as well as relevant references.  The primary outcomes were 24-hour triglyceride reduction rate and in-hospital mortality.  A total of 791 studies were retrieved; 15 observational studies (1,080 subjects) were included, most of which were historical cohort studies.  Compared with conventional treatment, plasmapheresis aided in lowering serum triglyceride (TG) levels in the first 24 hours following hospital admission (standardized MD [SMD]: 0.58; 95 % CI: 0.17 to 0.99; p = 0.005).  However, it resulted in increased hospitalization costs (1,000 yuan) (WMD: 24.32; 95 % CI: 12.96 to 35.68; p < 0.001).  With regard to in-hospital mortality, although the mortality rate in the plasmapheresis group was higher than that in the conventional treatment group (RR: 1.74; 95 % CI: 1.03 to 2.94; P = 0.038), the result was disturbed by confounding factors as per the subgroup and sensitivity analysis, as well as trial sequential analysis (TSA).  No significant differences were found in other outcomes, including systematic complications, local complications, the requirement for surgery, and hospitalization duration.  The authors concluded that the effect of plasmapheresis in HTG-induced AP was not superior to that of conventional treatment, even resulting in a greater economic burden to patients and healthcare system.

An UpToDate review on “Hypertriglyceridemia-induced acute pancreatitis” (Gelrud and Whitcomb, 2023) states that “In patients with HTG-induced pancreatitis (HTGP) (serum triglyceride level > 1000 mg/dL plus lipase > 3 times the upper limit of normal) and worrisome features (hypocalcemia, lactic acidosis, signs of worsening systemic inflammation or organ dysfunction, and/or multi-organ failure), we suggest treatment with plasmapheresis (Grade 2C).  Triglyceride levels should be monitored every cycle of plasmapheresis.  We continue plasmapheresis until triglyceride levels are < 500 mg/dL (5.6 mmol/L)”.


References

The above policy is based on the following references:

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