Life-threatening thrombotic thrombocytopenic purpura (TTP) in a patient with sickle cell-hemoglobin C disease.

We report a patient with hemoglobin sickle cell-hemoglobin C disease who developed the clinical syndrome of thrombotic thrombocytopenic purpura (TTP) during admission for typical acute pain crisis. The potential for multiorgan involvement secondary to vaso-occlusive crisis complicated the diagnosis and overlapped with the patient's clinical presentation of chronic bone pain and hemolytic anemia. Clinical improvement and normalization of laboratory parameters followed rapidly in response to plasma exchange therapy.