Actinobacillus actinomycetemcomitans endocarditis: a report of four cases and review of the literature.

Four patients with infective endocarditis caused by Actinobacillus actinomycetemcomitans seen at the National Taiwan University Hospital between January 1985 and December 1990 are reported. There were two men and two women with a mean age of 40 years. Three had had a xenograft replacement, the other one had prolapse of mitral valve. Carious teeth were noted in two. The most common presenting symptoms were fever, cough, dyspnoea, and weight loss and the duration of symptoms before diagnosis varied from 2 weeks to 2 months. Peripheral stigmata of endocarditis were not present in any patient. Laboratory investigation revealed haematuria and anaemia in three patients, and elevated erythrocyte sedimentation rates in all four. None had leucocytosis. Echocardiography was performed more than once for each patient and vegetation was demonstrated in only one. Blood culture became positive after 7-10 days of incubation. One of the isolates was resistant to penicillin. The diagnosis was delayed due to the indolent clinical course, non-specific presentation, and the slow growth of the organism. However, all patients were cured clinically and bacteriologically after 6 weeks of intravenous antibiotic therapy which included penicillin, cefamandole, chloramphenicol, or aztreonam, with or without an aminoglycoside. All patients were free of evidence of recurrence after 6-25 months of follow-up.