Summary

A 13-year-old male patient with a history of pre-B cell acute lymphoblastic leukaemia (ALL) with isolated central nervous system relapse on maintenance chemotherapy presented with severe thrombocytopenia refractory to platelet transfusions. The patient showed only modest responses to two courses of intravenous immunoglobulin and steroids. He was found to be positive for cytomegalovirus (CMV) with modest viral load. His thrombocytopenia normalised with rituximab therapy and CMV treatment supporting the diagnosis of CMV-associated immune thrombocytopenic purpura (ITP). Following treatment, the patient continued to have a stable platelet count well above the threshold for transfusions. He continued to be intermittently treated for CMV when viral loads became detectable. This report discusses the unique management considerations of ITP in a patient undergoing therapy for ALL with a review of previously reported cases and discusses the possibility of CMV viraemia as a modulating factor.