Corynebacterium CDC Group G Native and Prosthetic Valve Endocarditis

We report the first case of native and recurrent prosthetic valve endocarditis with Corynebacterium CDC group G, a rarely reported cause of infective endocarditis (IE). Previously, there have been only two cases reported for prosthetic valve IE caused by these organisms. A 69-year-old female with a known history of mitral valve regurgitation presented with a 3-day history of high-grade fever, pleuritic chest pain and cough. Echocardiography confirmed findings of mitral valve thickening consistent with endocarditis, which subsequently progressed to become large and mobile vegetations. Both sets of blood cultures taken on admission were positive for Corynebacterium CDC group G. Despite removal of a long-term venous access port, the patient’s presumed source of line associated bacteremia, mitral valve replacement, and aggressive antibiotic therapy, the patient had recurrence of vegetations on the prosthetic valve. She underwent replacement of her prosthetic mitral valve in the subsequent 2 weeks, before she progressed to disseminated intravascular coagulation and expired. Although they are typically considered contaminants, corynebacteria, in the appropriate clinical setting, should be recognized, identified, and treated as potentially life-threatening infections, particularly in the case of line-associated bacteremias, and native and prosthetic valve endocarditis.