Frequency of occurrence and antimicrobial susceptibility of bacterial isolates from the intestinal and female genital tracts.

In the selection of empiric therapy for infections of the female genital tract and intraabdominal infections in humans, the requisite information includes (1) the frequency of isolation of bacterial species dominant in the normal gastrointestinal and female genital tracts and in intraabdominal and female genital tract infections and (2) the in vitro susceptibilities of the dominant species to drugs that may be used against them (e.g., penicillin G, cefoperazone, cefoxitin, chloramphenicol, clindamycin, and metronidazole). The predominant bacteria in fecal contents are not necessarily those most frequently found in infections. Intraabdominal and perirectal infections are usually polymicrobial, resulting from mixtures of facultative species (coliforms and streptococci) and anaerobes. The predominant bacteria of the normal vagina and cervix are lactobacilli, facultative streptococci, Peptococcus species, and Peptostreptococcus species. Most infections of the female genital tract are due to mixtures of facultative enteric bacilli, streptococci, and anaerobes (Peptococcus and Peptostreptococcus species, Bacteroides fragilis, Bacteroides disiens, Bacteroides melaninogenicus, Bacteroides bivius, and Bacteroides asaccharolyticus). Of the antibiotics tested, clindamycin appears the most active against many of the groups of bacteria isolated.