A severe case of cefoxitin-induced immune hemolytic anemia

Drug-induced immune hemolytic anemia is a rare but underdiagnosed and potentially fatal condition. We report a case of severe hemolytic anemia induced by cefoxitin in a 45-year-old woman admitted with menometrorrhagia. Hemoglobin levels reached a nadir of 4.7 g/dl approximately 72 h after cefoxitin initiation, and hemolysis resolved when cefoxitin was discontinued and prednisone 1 mg/kg was initiated. A transfusion reaction workup revealed no abnormalities. Direct antiglobulin testing was weakly positive with anti-C3. The patient's plasma and RBC eluate reacted with cefoxitin-treated RBCs but not with untreated RBCs in the presence or absence of cefoxitin.