Primary actinomycotic endocarditis: case report and review.

Endocarditis due to Actinomyces species for which a portal of entry cannot be identified is extremely rare. We present a case of primary endocarditis due to Actinomyces israelii with an unknown portal of entry and review seven similar cases reported in the literature since 1939. The disease predominantly affects males. Clinical features are similar to those of bacterial endocarditis due to other organisms. Penicillin remains the drug of choice for treatment of this condition. The optimal duration of treatment has not yet been determined; however, with early diagnosis and appropriate antimicrobial therapy, the prognosis is good.