POSTTRANSFUSION PURPURA (PTP) ASSOCIATED WITH ANTI-HPA-1A, ANTI-HPA-2B AND ANTI-HPA-3A ANTIBODIES

The serum from an 85-year-old man with a clinical diagnosis of post-tr ansfusion purpura (PTP) was investigated for the presence of platelet- specific antibodies. Clinically, the case was typical of PTP but, unus ually, the serum was found to contain multiple platelet-specific alloa ntibodies. Anti-HPA-1a, anti-HPA-2b and anti-HPA-3a antibodies were de tected together with multispecific anti-HLA (class I) antibodies. Addi tional (but weaker) antibody reactivity was also observed with platele t glycoproteins (Gp) IIb/IIIa, GpIb and GpIa/IIa which lacked the anti gens recognized by the alloantibodies, suggesting the presence of auto -or cross-reacting antibodies. The patient's genotype was HPA-1b/1b, H PA-2a/2a, HPA-3b/3b, HPA-5a/5b and was consistent with the platelet al loantibodies detected. The patient made a complete recovery following treatment with intravenous gamma-globulin.