Incidence of allergic reactions with fresh frozen plasma or cryo-supernatant plasma in the treatment of thrombotic thrombocytopenic purpura. Reutter JC, Sanders KF, Brecher ME, Jones HG, Bandarenko N. Journal of Clinical Apheresis 2001;16(3):134-138.

Plasma replacement for thrombotic thrombocytopenic purpura (TTP) is accomplished with various plasma products. Adverse reactions associated with therapeutic plasma exchange (TPE) are estimated at 9.7%, although severe reactions are uncommon (less than 1%). The most common complications include citrate toxicity, allergic reactions, and volume shifts. Several studies have shown fewer complications when albumin is used compared to plasma products. Plasma replacement is essential in the treatment of TTP and currently includes fresh-frozen plasma (FFP), cryosupernatant plasma (CPP) and solvent detergent treated plasma. The differences in these products may affect the frequency of allergic complications. This study sought to determine the incidence of allergic reactions with FFP or CPP as replacement in TPE. Forty-one TTP patients were identified retrospectively between 1982 and 1999 at the University of North Carolina Hospitals who received TPE replacement with either FFP (n=21) or CPP (n=20). Antihistamine was administered following the initial occurrence of an allergic reaction (urticaria, respiratory distress, or anaphylaxis with hypotension). Fifty-one allergic reactions occurred in 65.8% of patients. Urticaria comprised 49 of 51 (96%) of reactions and respiratory distress the remaining 4%. No anaphylaxis occurred. Nineteen urticarial reactions occurred in 50% of CPP recipients compared to 71% of FFP recipients, which was not a statistically significant difference. Antihistamine breakthrough occurred in 36.3% of patients who experienced a previous allergic reaction with CPP and 37.5% with FFP, although this also was not statistically significant. The overall risk of allergy per unit of plasma was 1.37% (1.23 % CPP, 1.48% FFP), comparable to estimates in non-TTP recipients. The median number of donor exposures preceding the first allergic reaction and the mean volume of plasma transfused prior to reaction was similar between CPP and FFP. Neither product was advantageous in preventing allergic complications. Because of the large volume, the number of donor exposures, and prolonged duration of therapy, allergic reactions to plasma are common (65.8%) in the treatment of TTP. While antihistamine treatment is prudent with the onset of allergy, it may be insufficient in up to one-third of patients in preventing recurrent allergic complications. Medical and nursing management of these adverse reactions should be anticipated, regardless of the choice of plasma product.