Native valve endocarditis due to Corynebacterium striatum: case report and review

We report the first known case of native valve endocarditis due to Corynebacterium striatum and review 51 previously reported cases of native valve endocarditis due to non-diphtheriae corynebacteria. Of the 52 patients with corynebacterial endocarditis, 11 (21%) had no predisposing conditions and 27 (52%) had structural heart disease; endocarditis in the remaining 14 patients (27%) was associated with noncardiac predisposing factors including injection drug use, chronic hemodialysis, vasculitis, alcoholism, liver transplantation and hemodialysis, a peritoneovenous shunt, and prior aspiration of a noninfected bursa. The mortality rate associated with corynebacterial endocarditis was 31%. The majority of corynebacteria in this series were sensitive to penicillin, erythromycin, gentamicin, and vancomycin. Non-diphtheriae corynebacteria are capable of producing acute valvular damage, even in patients without conditions that are predisposing for endocarditis. The occurrence of bacteremia due to non-diphtheriae corynebacteria in the appropriate clinical setting should alert physicians to the possible diagnosis of endocarditis. Empirical antibiotic therapy with vancomycin, with or without an aminoglycoside, should be initiated pending antibiotic susceptibility testing.