[Detection of anti-IgA alloantibody in a case of non-hemolytic transfusion reaction].

A 59-year-old man with myelodysplastic syndrome exhibited unticaria, dyspnea, fever, and hypotension immediately after the start of platelet concentrate (PC) transfusion on the 15th day of hospitalization. On the 17th and 21st day of hospitalization, the patient exhibited severe unticaria resembling that of erythroderma after the start of PC transfusion. Anti-IgA IgG antibody was detected by enzyme-linked immunosorbent assay (ELISA) on the 28th day of hospitalization. Anti-IgA (purified from pooled human plasma) was detected by Western blotting. The patient's IgA level was normal. No antibodies against HLA or platelet-specific antigens were detected in serum. The patient had no reaction to administration of washed PC. These findings suggest that anti-IgA antibody might have been responsible for the nonhemolytic transfusion reaction in this patient.