The Food and Drug Administration (FDA) licensed Rho(D) immune globulin intravenous (anti-D IGIV) in March 1995 for treatment of immune thrombocytopenic purpura (ITP). The presumed mechanism of action of anti-D IGIV is extravascular hemolysis of anti-D-sensitized RBCs by splenic macrophages. Although seemingly inconsistent with this mechanism of action, acute hemoglobinemia and hemoglobinuria have been reported and are listed in the professional package insert for anti-D IGIV as possible adverse events. Through November 30, 2004, FDA received 6 reports of disseminated intravascular coagulation (DIC) associated with “acute hemolysis” (or similar terms) following anti-D IGIV treatment for ITP (Gaines AR. Disseminated intravascular coagulation associated with acute hemoglobinemia or hemoglobinuria following Rho(D) immune globulin intravenous administration for immune thrombocytopenic purpura.
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). All patients were clinically stable and were initially discharged home following anti-D IGIV administration. All were subsequently hospitalized for signs and symptoms of acute hemolysis or DIC. The mean decrease between pretreatment and nadir posttreatment hemoglobin levels was 5.8 g/dL (range: 3.0 to 9.6 g/dL); 4 patients received 2 to > 5 units of packed RBCs. Four patients whose baseline serum creatinine levels were within normal limits developed renal insufficiency; 2 of those patients underwent dialysis. The pediatric patient was subsequently discharged from the hospital without sequelae. However, all 5 adult patients remained hospitalized and died 3 to 10 days after anti-D IGIV administration. Attending or consulting physicians assessed that acute hemolysis and/or DIC caused or contributed to each death. Data from previously reported cases further suggested that previous uneventful administration of anti-D IGIV does not preclude the development of acute hemolysis upon subsequent administration of anti-D IGIV. These cases suggested that patients treated with anti-D IGIV for ITP who experience acute hemoglobinemia or hemoglobinuria be monitored for the development of DIC. To increase our knowledge about the seemingly rare but potentially serious complication of DIC following anti-D IGIV treatment for ITP, physicians and other health care professionals are encouraged to submit serious adverse event reports to the anti-D IGIV manufacturer or to FDA. Contact information for reporting adverse events to the manufacturer of any FDA-approved product is generally available in the professional package insert or on manufacturer- or distributor-sponsored web sites. Alternatively, adverse events can be reported directly to FDA through its adverse event reporting system, MedWatch, by Internet at http://www.fda.gov/medwatch, by telephone at 1-800-FDA-1088; by fax at 1-800-FDA-0178; or by mail at MedWatch, HF-2, 5600 Fishers Lane, Rockville, MD 20852-9787.