Endocarditis caused by Streptococcus morbillorum.

Although patients with nutritionally variant streptococcal endocarditis have been reported in recent years, the specific clinical features of this disease have not been well characterized. We report here the clinical and laboratory features of a particularly unusual case of persistent bacteremia caused by Streptococcus morbillorum , one of the nutritionally variant streptococci. The patient was successfully treated with a combination of penicillin and rifampin after two treatment failures. We also review cases of nutritionally variant streptococcal endocarditis published in the English literature since 1971, in an attempt to understand some difficulties encountered in diagnosing and treating this type of endocarditis.