AN EVALUATION OF INTRAVENOUS IMMUNOGLOBULIN IN THE TREATMENT OF HUMANIMMUNODEFICIENCY VIRUS-ASSOCIATED THROMBOCYTOPENIA

Background: Anecdotal evidence suggests that high-dose intravenous imm unoglobulin (IVIG) is useful in the management of human Immunodeficien cy virus (HIV)associated thrombocytopenia. Study Design and Methods: T o rigorously evaluate this therapy, a crossover study was designed to compare IVIG, given at 1 g per kg per day for 2 consecutive days each week for 4 weeks, with intravenous saline placebo administered accordi ng to the same schedule. Subjects were randomly assigned to receive ei ther IVIG or saline during the first 4 weeks; if IVIG was given, there was a 4-week period of no therapy before beginning placebo administra tion. Criteria for eligibility were platelet count of less than 50,000 per mu L (50 x 10(9)/L), elevated platelet-associated IgG levels, inc reased megakaryocytes In the bone marrow, and positive HIV antibody te st. Twelve patients (11 men, 1 woman) were studied. Seven patients com pleted the full protocol. Four dropped out: after 2, 5 (2 patients), a nd 8 weeks that included at least 2 weeks of IVIG. Results: All patien ts sustained an increase in platelet count in response to IVIG, with i ncrements ranging from 15,000 to 358,000 per mu L (15 to 350 x 10(9)/L ) (mean, 180,000/mu L [180 x 10(9)/L]; median, 174,000/mu L [174 x 10( 9)/L]). No patient had an increase after placebo infusions. There were no adverse effects of treatment, and weekly chemical analyses showed no new abnormalities except for mild elevations in the serum protein. The duration of responses ranged from 2 to 10 weeks. No patient demons trated refractoriness to IVIG. Conclusion: IVIG consistently raises pl atelet counts in patients with HIV-associated thrombocytopenia.