Durable response to a single dose of Anti D in immune thrombocytopenic purpura in an adult with underlying human immunodeficiency viral infection

Abstract

Dear Editor, We report a case of steroid refractory human immune deficiency virus-related immune thrombocytopenic purpura (HIV-TP) successfully treated with single dose of intravenous Anti-Rh (Anti D). Although anti-retroviral treatment is the preferred first option in this situation, we treated him with steroids and, subsequently, with Anti D partly according to the patient’s wishes. He showed a durable response (nearly 2 years now) to a single dose of treatment. We propose that Anti D should be considered before antiretroviral treatment, at least in some patients. A 25-year-old man was referred to the haematology unit for further investigation of symptomatic thrombocytopenia. He had a known history of HIV infection for 5 years but has been asymptomatic till this point. The laboratory examination showed platelet count of 30×10/L with normal white cell count and haemoglobin. All other biochemical and haematological parameters were normal. The CD4/CD3 count on peripheral blood was 450/μL. On further investigations, the bone marrow aspirate showed increased megakaryocytes compatible with a diagnosis of peripheral consumption as the cause for low platelet count. A provisional diagnosis of ITP was made and he was treated with steroids without any response. A dose of Anti D gave an excellent initial response to the therapy, acquiring a platelet count of over 200×10/L. Subsequently, the platelet count fluctuated between 185×10/L and 50×10/L; but despite only having a single dose of therapy, he has been asymptomatic and did not need any further treatment. The variability of platelet count during the course of disease is illustrated on Fig. 1. HIV is one of the many causes of secondary ITP. Thrombocytopenia was associated with AIDS even before the discovery of HIV [1]. While a number of different mechanisms have been reported by which HIV infection could produce thrombocytopenia, the ability of effective anti-retroviral therapy to improve platelet counts demonstrates a close association between HIV replication and thrombocytopenia. Probable mechanisms of thrombocytopenia include anti-platelet glycoprotein antibodies; antiHIV antibodies that cross-react with platelet membrane glycoproteins, platelet clearance due to immune complex disease and decreased platelet production/ineffective erythropoiesis. Thrombocytopenia is more common in patients with advanced HIV with CD4 lymphocyte count of less than 200/μL [2]. Interestingly, our patient had thrombocytopenia with normal CD4 count. HIV-TP has been shown to correlate with the degree of HIV viral load [3] and respond well to anti-retroviral treatment [4]. Hence, highly active anti-retroviral therapy (HAART) is considered as the first port of treatment [5]. Our patient did not agree with this option, so we had to consider either steroids, splenectomy, Ann Hematol (2009) 88:1155–1156 DOI 10.1007/s00277-009-0744-4