BOF: Transfusion (Plasma Products)

Therapeutic plasma exchange and intravenous immunoglobulin are often used for the same indications, and each may be unavailable due to lack of equipment, staff, or supply and manufacturing problems. Under which one of the following circumstances would plasmapheresis NOT be a reasonable alternative if intravenous immunoglobulin is not available?

a) Chronic inflammatory demyelinating polyneuropathy

b) Guillain Barre syndrome

c) Immune thrombocytopenic purpura

d) Myaesthenia Gravis

e) Post-transfusion purpura

Answer:

Haemoglobin less than 7g/dl

Explanation:

While there are case series describing success of plasma exchange in treating immune thrombocytopenic purpura it remains controversial, and generally further depletes platelets by 10-15%. Being pathological autoantibody-mediated, all of these conditions are theoretically amenable to treatment with intravenous immunoglobulin, through overwhelming the pathological antibody with non-specific antibodies, and therapeutic plasma exchange by directly depleting the pathological antibody. However neither have a robust evidence base for efficacy, based largely on anecdotal experience and small case series, but continue to be applied in clinical practice.

Reference:

Howell C, Douglas K, Cho G, et al.: Guideline on the clinical use of apheresis procedures for the treatment of patients and collection of cellular therapy products. Transfus Med 2015; 25:57–78