Autoimmune hemolytic anemia or pure red cell aplasia, AIHA: Hemolytic anemia Hemoglobin less than 10.0 g/dL without transfusion Hemolysis as evidenced by both: Sustained reticulocytosis (greater than 125,000/mm3) without evidence of active bleeding or increasing hemoglobin Laboratory evidence of hemolysis Positive direct antiglobulin test or equivalent immune adherence test No evidence for paroxysmal nocturnal hemoglobinuria Negative Ham's test and sucrose hemolysis. For PRCA: Anemia due to selective decrease in marrow erythroid precursors Hemoglobin less than 10.0 g/dL without transfusion Severe reticulocytopenia (less than 20,000/mm3 despite anemia) Severely decreased marrow erythroid precursors Positive marrow coculture with serum or cells or response to immunosuppression No evidence for PNH Negative Ham's test and sucrose hemolysis Severe disease: Chronic (i.e., greater than 1 year) Transfusion dependent or untransfused hemoglobin less than 8.0 g/dL Ferritin greater than 2,000 or evidence of organ dysfunction due to iron overload Refractory to conventional therapy after all 3 of the following: High dose steroids (at least 1 mg/kg) for at least 21 days Splenectomy (except cold reactive antibodies) 1 additional immunosuppressive therapy OR Controlled on conventional therapy but at price of unacceptable toxicity