"Anti-platelet antibodies" in HIV infected haemophiliacs.

We have studied anti platelet antibodies and circulating immunocomplexes in 16 haemophiliacs with mild thrombocytopenia eight of which were infected by human immunodeficiency virus (HIV). No difference in platelet count was observed between HIV+ (143 +/- 31 x 10(9)/l) and HIV- patients (148 +/- 30 x 10(9)/l). On the contrary, HIV+ haemophiliacs had serum platelet bindable IgG (SPBIgG), normal platelet associated IgG (PAIgG), high serum IgG and circulating immunocomplexes (CIC). Considering all 16 patients serum IgG correlated with CIC (r = 0.7 p less than 0.01) and SPBIgG (r = 0.6 p less than 0.01) respectively. We obtained also a positive correlation between serum CIC and SPBIgG (r = 0.51 p less than 0.05). Immunoblotting of patients' sera showed no specific binding to target platelet antigens. In conclusion there is no evidence of HIV related immune thrombocytopenia in our haemophiliacs but the study confirms the appearance of immunocomplexes in the HIV+ subjects.