Aplastic anemia successfully treated with rituximab

An otherwise healthy 73-year-old female was admitted to our department in 1997 because of easy bruising and a platelet count of 12 x 10(9)/L. The patient was taking no medications. Bone marrow examination revealed erythroid hyperplasia, megakaryocytic hypoplasia, and no sign of malignancy. Chromosome analysis showed a normal karyotype. There was serological evidence of previous infection with parvovirus B19. No antibodies to HBV, HCV, CMV, or EBV were found. ANA and cardiolipin antibodies were not detected. Treatment with prednisolone was without effect, but 3 weeks after i.v. gamma-globulin therapy, the platelet count was normal, 233 x 10(9)/L. Two years later, the patient was readmitted with a platelet count of 11 x 10(9)/L. At this time, treatment with corticosteroids, azathioprine, and gamma-globulin had only a temporary effect, and further therapy was stopped because of side effects. During the next 3 years, the patient developed transfusion-dependent anemia, and her white blood cell count decreased to 1.8 x 10(9)/L. A new bone marrow examination showed aplastic anemia with bone marrow cellularity about 10%. After an intracerebral hemorrhage, the patient accepted treatment with rituximab and received 4 weekly doses of 375 mg/m2. This therapy was followed by an increase in the platelet count to 232 x 10(9)/L, white blood cell count to 6.8 x 10(9)/L, and no more need for blood transfusions. A bone marrow examination 5 months after treatment with rituximab showed hyperplastic myelopoiesis, normoblastic erythropoiesis, and slightly reduced megakaryopoiesis. The use of anti-CD20 monoclonal antibody in aplastic anemia warrants further investigation.