Current problems in antibiotic treatment in obstetrics and gynecology

Abstract

Recent developments that influence patterns of antibiotic prescription for obstetric-gynecologic patients include a better understanding of the multibacterial dimensions of pelvic infections, the introduction of new antibiotics, and the pressures for cost-containment in medical care. Prophylaxis has become established as effective for prevention of infection following vaginal hysterectomy and cesarean section, but its success in abdominal hysterectomy has been less uniform. For patients with pelvic infections, the poorest clinical response occurs in those whose infection is well established before initiation of therapy. Because gram-negative anaerobic bacteria often are present in such infections, the selection of antibiotics should be based on the susceptibility patterns of the infecting organism(s) and on the ability of the agent to reduce high counts of anaerobic bacteria. Both metronidazole and clindamycin meet these criteria. Controlled studies of infections seen early in the clinical course are few. The initial selection of agents effective against gram-negative anaerobes seems important in the treatment of endomyometritis following cesarean section, whereas curettage seems the most significant therapy for infections following abortion.

PIP: More sophisticated knowledge of the microbiologic components of pelvic infection, the availability of several new antimicrobial agents, and pressures to control medical costs are contributing to changes in antibiotic prescribing patterns in hospitals in the US. The use of prophylactic antibiotics is the area that has undergone the greatest change in the field of obstetrics and gynecology. Prophylactic antibiotics are widely administered after cesarean section to prevent postpartum soft tissue infections. The combination of clindamycin and an aminoglycoside, or single-agent therapy with a newer cephalosporin or penicillin, results in a higher success rate than the previous regimen of penicillin G and an aminoglycoside. Women given prophylactic antibiotics in conjunction with vaginal hysterectomy also demonstrate a reduced incidence of postoperative uterine infections; in abdominal hysterectomy, the utility of this approach is not as obvious. For patients with pelvic infections, those with early infection (symptoms for 4 days or less and no indurated mass) are more likely to be cured by antibiotics and less likely to require operative intervention than those with more advanced infection. The selection of antibiotic in cases of pelvic infection should be based on the susceptibility patterns of the organism and the antibiotic's ability to reduce high counts of anaerobic bacteria. Both metronidazole and clindamycin meet these criteria.