ZIDOVUDINE INDUCED PURE RED CELL APLASIA

48 year old gentleman from Andhra Pradesh presented with 10 days history of cough with muco-purulent expectoration and 2 days history of fever. He also complained of shortness of breath on exertion and fatigability at the onset of cough. He denied any history of gum or GIT bleed.His past medical history revealed that he has been diagnosed to have HIV-1 infection, pulmonary tuberculosis at local hospital in May, 2009. The baseline CD4-T cell count was 104 cells liter at the time of diagnosis. Following Anti-Tubercular therapy (Category-1 regimen under RNTCPDOTS) and Anti-Retroviral Therapy (Zidovudine, Lamivudine and Efavirenz), there was significant improvement in his clinical condition and his CD4-T cell count was 260 cells liter at the end of 3 months. At the time of presentation his physical examination showed marked pallor. However there was no Lymphadenopathy or oro-cutaneous lesions. Respiratory system examination revealed bilateral coarse crepitations in all areas of lung fields. His initial laboratory investigations showed macrocytic anemia with poor reticulocyte response suggestive of hypo-proliferative anemia. His Vitamin B-12 and Folate levels were adequate. Bone Marrow examination showed marked erythroid hypoplasia and adequate iron stores. Hence he was diagnosed to have Zidovudine Induced PRCA. His zidovudine was withdrawn and the Anti -retroviral medications were changed to L a m i v u d i n e , S t a v u d i n e a n d Efavirenz.Zidovudine-induced anemia has usually been reported as macrocytic and megaloblastic. Reversible pure red cell aplasia is a rare complication of both zidovudine and Lamivudine, typically occurring within the first 3 months of therapy. This case highlights 2 rare complications of Zidovudine toxicity. Firstly, the zidovudine induced pure red cell aplasia which is a relatively rare toxicity. Secondly, the red cell aplasia presented after 18 months of initiation of Zidovudine. Keyword :HIV, Zidovudi