[A clinical investigation of infective endocarditis at a community hospital in Japan]. 
There have been few reports on the clinical features of infective endocarditis (IE) in Japan.  We clinically investigates 45 episodes (36 cases) of definite IE that were experienced from January 1985 to March 1997 at a community hospital, Okinawa Chubu Hospital, Okinawa, Japan.  Regarding age, prior dental procedure, causative organisms and sites of infection, analyses and comparison were performed on a total of 94 episodes, by adding another 49 episodes of IE that were experienced between 1977 and 1984 at our hospital.  The mean age was 47 years and majority of patients in the recent 12 years were older than 50 years of age.  Mortality of all 94 episodes was 20%, while that of recent 45 cases was 13%.  Eight % of all episodes had history of recent dental treatment but significance of the finding remains unclear.  Alpha streptococci were most common (33%) and Staphylococcus aureus was the second most common organism (17%).  Eleven % of all episodes were culture-negative and there was a statistically significant difference in the histories of prior antibiotic therapy between culture-negative and culture-positive episodes.  Regarding sites of infection, 27% of all episodes involved mitral valves, while 24% involved aortic valves.  Prosthetic valves were involved in 12%.  Ninety-eight % of the recent episodes had fever, 98% had cardiac murmurs and 27% had characteristic mucocutaneous lesions.  Heart failure was the most common complication (27%) and half of the cases with prosthetic valve infection had heart failure.  Cerebral embolism was most frequently seen among the major arterial embolic complications.  Our results were similar to those which were previously reported from other countries.  We should have a high index of suspicion for endocarditis whenever we see patients who present various clinical manifestations and fever of which origin remains unclear.  Willingness to obtain blood culture before starting antibiotics is most important.