An unusual course of invasive infection due to nontoxinogenic strain of Corynebacterium diphtheriae.

The authors report a case of complicated sepsis caused by nontoxigenic Corynebacterium diphtheriae biotype gravis in a young immunocompetent female with no predisposing factors. She acquired the infection from her boyfriend, an asymptomatic carrier of nontoxigenic strain. The primary site of infection and subsequent sepsis was not identified. The occurence and importance of carriage and invasive infections caused by nontoxigenic strains of Corynebacterium diphtheriae are discused.