Use of intravenous immunoglobulin in chronic lymphocytic leukemia.

Five patients with clinical stage III and IV chronic lymphocytic leukemia were treated with a five-day infusion of high-dose intravenous immunoglobulin for either autoimmune hemolytic anemia or immune thrombocytopenic purpura or by a dose of intravenous immunoglobulin G every three to four weeks for prevention and control of infections associated with hypogammaglobulinemia. The hematocrit level stabilized with a decrease in red blood cell destruction by intravenous immunoglobulin G in chronic lymphocytic leukemia patients with AIHA without altering red blood cell autoantibody titers, but severe hemolysis recurred after 21 days. A long-term remission was observed when intravenous immunoglobulin G was combined with steroids, chemotherapy, plasmapheresis, and splenectomy. The platelet count increased and platelet transfusion requirement was eliminated in a chronic lymphocytic leukemia patient with immune thrombocytopenic purpura by the intravenous immunoglobulin G, and chemotherapy was administered and a complete remission resulted. An interesting observation was the lymphocytopenic effects observed in the five patients during a daily infusion of intravenous immunoglobulin for five days. Furthermore, the maintenance intravenous immunoglobulin G given every three weeks controlled both infections and lymphocyte counts with the chemotherapy. Changing the schedule to every four weeks resulted in poor control of the lymphocyte counts with chemotherapy. These observations indicate a direct macrophage blocking effect in autoimmune hemolytic anemia and immune thrombocytopenic purpura, but the lymphocytopenic effect suggests immunomodulating effects of intravenous immunoglobulin G, which may alter the response of chronic lymphocytic leukemia cells to chemotherapy.