A hemolysis verified to be induced by anti-meropenem

Incompatibility of blood groups or unexpected antibodies are primary considerations when acute hemolysis occurs during or after transfusion. However, less attention is paid to drug-induced immune hemolytic anemia (DIIHA), which is a rare but potentially life-threatening autoimmune disease. We present the case of a 34-year-old woman (group A, RhD+) who was treated with multiple antibiotics after meningioma resection. As her hemoglobin (Hb) decreased significantly from 109 g/L to 52 g/L without obvious bleeding, a blood transfusion was conducted soon after the medication, during which acute hemolysis occurred. An unexpected antibody, anti-M (MNS blood group system), was identified in the patient. It was confirmed that both the recipient and donor were group A, M antigen negative (M−) with CCDee phenotype, and no agglutination reactivity was observed in major crossmatch by testing the specimens before and after transfusion. Meanwhile, the results of the direct antiglobulin test (DAT) changed from negative to positive. Anti-meropenem, a drug-dependent antibody of meropenem, was detected, and hemolysis resolved after cessation. Anti-meropenem may mainly act through an "immune complex-type" reaction that induces intravascular hemolysis. Notably, the peculiarity of this case was dependent on the occurrence time of the acute hemolysis. Hence, it is necessary to raise awareness of DIIHA in clinical antibiotic treatments.