Successful treatment of pure red cell aplasia with rituximab in patients with chronic lymphocytic leukemia.

Pure red cell aplasia (PRCA) is a rare complication in patients with chronic lymphocytic leukemia (CLL). It is characterized by reticulocytopenia and by an absence of red cell precursors in the bone marrow. Unlike autoimmune hemolytic anemia, which is characterized by an increased number of reticulocytes, positive Coombs test findings, and a high serum level of lactate dehydrogenase. Two patients with B-cell CLL are reported to have developed PRCA, one while on chemotherapy with fludarabine and one seeking treatment for de novo PRCA. Both responded dramatically to therapy with monoclonal antibody rituximab (Rituxan) in a short period of time and continued to be transfusion-independent. These are the first 2 reported patients for whom rituximab treatment for PRCA in CLL was successful, and this treatment deserves further investigation.