ENTEROCOCCUS, AN EMERGING PATHOGEN

OBJECTIVES: To review the bacterial genus Enterococcus with respect to its epidemiology, specific infections in humans, mechanisms of resist ance and tolerance, and antimicrobial treatment. DATA SOURCES: A MEDLI NE search of English-language journal articles published from 1977 to 1992 was completed. Articles published prior to 1977 were identified t hrough Index Medicus and from references appearing in the bibliographi es of other journal articles. information also was acquired from abstr acts, personal communication with infectious disease specialists with active research in the area of enterococcal infection, and conference proceedings. STUDY SELECTION: In vitro data; animal models of enteroco ccal infection; case reports; and case-controlled, cohort, and randomi zed controlled trials in humans were evaluated for relevant informatio n. DATA EXTRACTION: Studies were evaluated by their methodologic stren gth (e.g., randomized controlled trial), reporting of clinically relev ant outcomes (e.g., clinical response to antimicrobial therapy), stati stical analyses, and accountability of all patients who entered the st udy. DATA SYNTHESIS: The incidence of enterococcal infections has incr eased in recent years and enterococci are now the second most frequent ly reported nosocomial pathogens. Enterococcus faecalis is the pathoge n responsible for most enterococcal infections seen today; it has been implicated as an important cause of endocarditis, bacteremia, urinary tract infections, and intraabdominal infections. CONCLUSIONS: Enteroc occal infection is of particular concern clinically because of its res istance to several antibiotics. Controlled comparative clinical trials of antimicrobial therapy in humans are lacking for several enterococc al infections. Therefore, the recommendations for antimicrobial therap y presented in this review are guidelines that reflect our current und erstanding of antibiotics used for enterococcal infection.