Anti-plasticizer specific IgE is present in the serum of transfused patients

Sera from 29 patients who had reacted to a platelet (27) or packed red cell (2) transfusion and from 5 patients who had received platelets without reacting were collected over a 13-month period. The sera were assayed for total IgE, and IgE specific for ethylene oxide, phthalic anhydride, hexamethylene diisocyanate, methylene diphenyl diisocyanate, toluene diisocyanate, and mast cell tryptase. Three patients with reactions had elevated total IgE levels, and specific IgE was positive for hexamethylene diisocyanate in 2 of 28 (7.1%), methylene diphenyl diisocyanate in 1 of 29 (3.4%), and toluene diisocyanate in 14 of 27 (51.9%). No positives were found in patients without reactions and no patients had an elevated tryptase level. It is unlikely that anti-plasticizer hypersensitivity was responsible for the transfusion reactions, but the prevalence and significance of such antibodies in both the hospital population and the general population would merit further investigation.