Immunochemical Mechanisms of Penicillin Induced Coombs Positivity and Hemolytic Anemia in Man

Abstract

Penicillin therapy covalently coupled RBC [red blood cells] with benzylpenicilloyl (BPO) groups in vivo, and a dose dependence was Indicated. Coombs posltlvlty was found to be benzylpenicilloyl (BPO) specific at least In part, and correlate with a relatively high titered IgG [immunoglobulin] antibody response to penicillin. In one case, non-BPO-specific antibodies were partially responsible for Coombs positlvity. BPO-speclflc Coombs positlvity appears to result from specific binding of circulating BPO-antibodies to BPO-coupled RBC in vivo. Both relatively intense hapten coupling of RBC and a relatively high titered (and/or high avidity) antibody response appear necessary for Coombs posltlvlty.