Successful treatment of amegakaryocytic thrombocytopenia with anti-CD20 antibody (rituximab) in a pa
March 29th, 2008 | by admin |Successful treatment of amegakaryocytic thrombocytopenia with anti-CD20 antibody (rituximab) in a patient with systemic lupus erythematosus.
Abstract Amegakaryocytic thrombocytopenia is an extremely rare disorder in systemic lupus erythematosus, and its mechanism and treatment are still largely unknown. We describe a 42-year-old woman with systemic lupus erythematosus who presented various clinical manifestations of life-threatening amegakaryocytic thrombocytopenia (10,000 platelets/mm(3) with a marked decrease of megakaryocytes in the bone marrow), proteinuria, psychosis, refractory chylothorax, ascites, and type II diabetes caused by the anti-insulin receptor autoantibody. She was initially treated with prednisolone (25-50 mg/day) and cyclosporine A (200 mg/day) without any improvement in severe thrombocytopenia. However, her clinical symptoms, including platelet counts, dramatically improved, with a concurrent decrease in the anti-c-Mpl antibody, an autoantibody against the thrombopoietin receptor, after a subsequent treatment with rituximab (375 mg/m(2) intravenously, weekly, for two consecutive weeks). Our case suggested that amegakaryocytic thrombocytopenia in patients with systemic lupus erythematosus might be mediated by the anti-c-Mpl antibody and could be treated with rituximab through elimination of pathogenic B cells producing autoimmune antibodies.
Fukushima T, Dong L, Sakai T, Sawaki T, Miki M, Tanaka M, Masaki Y, Hirose Y, Kuwana M, Umehara H.
Division of Hematology and Immunology, Department of Internal Medicine, Kanazawa Medical University, Kahoku-gun, Ishikawa, Japan.