HIV-related chronic ITP is caused by an accelerated platelet destruction due to adsorption of circulating immune complexes and to specific anti-platelet antibodies, but perhaps also by a defective thrombopoiesis resulting from invasion of the megakaryocytes by the retrovirus. Treatment is needed when platelet numbers drop beneath 20.10(9)/L or when severe bleeding symptoms occur. Steroids, commercially available immunoglobulins for IV use, AZT and anti-Rh immunoglobulins can be administered, although relapses are frequent after withdrawal of the drugs. Recurrences after splenectomy are far less common, but the progression towards AIDS might be accelerated.