Acquired autoimmune thrombocytopenia after allogeneic bone marrow transplantation

Abstract
Summary A 29‐year‐old man in remission from acute myeloblastic leukaemia was treated by chemoradiotherapy and transplantation of bone marrow (BMT) collected from his HLA identical brother. Engraftment was documented on D12. Transient acute GVHD (grade II) appeared from D34. No infection complicated the BMT. Nevertheless severe thrombocytopenia persisted and was unresponsive to marrow donor platelet transfusion. The platelet immunofluorescence test demonstrated the autoimmune basis of the thrombocytopenia. This study suggests that the transient immune imbalance observed in the early post graft period could facilitate the appearance of autoimmune cytopenias. Prolonged thrombocytopenia may occur after bone marrow transplantation (BMT). This requires platelet support which could delay the discharge from hospital. Thrombocytopenia is mostly related to marrow insufficiency and/or viral infections. We report a case of severe autoimmune thrombocytopenic purpura (AITP) in a recipient of an allogeneic BMT.