Infective endocarditis caused by beta-hemolytic streptococci. The Infectious Diseases Society of America's Emerging Infections Network.

Infective endocarditis caused by beta-hemolytic streptococci is infrequently seen. Members of the Infectious Diseases Society of America's Emerging Infections Network (EIN) were polled for cases of beta-hemolytic streptococcal endocarditis that were seen between 1 January 1994 and 31 December 1996. Thirty-one cases were submitted by 22 members. The patients' ages ranged from 4 months to 79 years, and 18 (58.1%) were males. Prosthetic valve infection occurred in six cases and intravenous drug abuse was noted in only one case. Diabetes mellitus was noted in 10 patients (32.3%). Group B beta-hemolytic streptococci accounted for over two-thirds of isolates (21 [67.7%] of 31). Twenty-five patients (80.7%) developed complications of infective endocarditis, and 15 (48.4%) underwent surgical intervention with valvular revision or excision. Sixty-one percent (19 of 31) received aqueous crystalline penicillin G either as monotherapy or in combination with gentamicin sulfate. In contrast to previously published data, the mortality rate (12.9%) among patients in this survey was remarkably low. There was no infection relapse documented in 16 of the remaining 27 patients for whom posttreatment follow-up information was available.