Development of cold agglutinin autoimmune hemolytic anemia during treatment for pediatric acute lymphoblastic leukemia.

Autoimmune hemolytic anemia (AIHA) is a potentially fatal complication of many lymphoid malignancies. Those most often associated with AIHA include chronic lymphocytic leukemia, B-cell lymphomas, and Burkitt-type acute lymphoblastic leukemia (ALL) and are clonal populations of mature B cells. There have been no reports of patients with B-cell precursor ALL who developed AIHA while undergoing chemotherapy, but AIHA has been reported in a few patients with ALL after hematopoietic stem cell transplant. The authors describe a child with B-cell precursor ALL who developed cold agglutinin AIHA during maintenance treatment while in remission after infection with influenza B.