IMMUNOLOGICAL STUDIES OF ANAPHYLAXIS TO IRON DEXTRAN IN PATIENTS ON RENAL DIALYSIS

Systemic reactions resembling anaphylaxis have occurred after intraven ous (IV) iron-dextran administration, a treatment modality that has ac quired increased acceptance following the use of erythropoietin for th e anemia of patients with chronic renal diseases. Three such patients sustained anaphylactoid reactions immediately after receiving IV test doses of iron-dextran which were their only known exposures. In an eff ort to determine the mechanism of their reactions, we applied tests fo r (1) basophil degranulation by iron-dextran, basophil histamine relea se, (2) a type I anaphylactic reaction, specific IgE antibodies, and ( 3) an immune complex activation, specific IgG antibodies against iron- dextran. Six other patients with renal diseases sewed as controls, thr ee of whom had tolerated IV iron-dextran, and three without known expo sure. One patient only had any test abnormalities. Her initial positiv e basophil histamine release and specific IgG antibodies reversed and declined respectively at a 4-month follow-up study. She had developed anaphylaxis, and her studies had been performed at a time after anaphy laxis earlier than the other two. The mechanisms of iron-dextran anaph ylaxis may be multiple and not be detectable several months after the incident. Prospective studies will probably be required for a predicti ve test to be developed.