Rapid progression of acquired amegakaryocytic thrombocytopenia to aplastic anemia.

Acquired amegakaryocytic thrombocytopenia is a rare disorder characterized by severe thrombocytopenia and selective, marked decrease or absence of megakaryocytes. Although immunosuppressive therapy (prednisone and/or antithymocyte globulin) has been shown to induce remissions in a subset of patients, most patients do not respond, and progression to aplastic anemia occurs in some cases. We report a case of acquired amegakaryocytic thrombocytopenia which, despite aggressive immunosuppressive treatment, rapidly progressed to aplastic anemia. Clinical, laboratory, and immunologic features of our patient's case are described and compared to those of the previously reported six cases that progressed from amegakaryocytic thrombocytopenia to aplastic anemia.