Abstract
Rothia dentocariosa is a rare gram-positive bacterial organism, one of the group of microbes that normally resides in the mouth and respiratory tract. R. dentocariosa rarely causes disease. Documented cases occur chiefly in patients with valvular or dental disease, or both. We report the case of a previously healthy 58-year-old man who presented with evidence of bacterial endocarditis caused by this organism-which originated from an elusive source. His endocarditis was successfully treated with mitral valve replacement and the administration of antibiotic agents.