Randomized comparison of ampicillin-sulbactam to cefoxitin and doxycycline or clindamycin and gentamicin in the treatment of pelvic inflammatory disease or endometritis

Objective: To evaluate the efficacy and safety of ampicillin sulbactam (3 g every 6 hours) in patients with pelvic inflammatory disease or postpartum endometritis using a randomized, comparative, multicenter study of parallel design. Methods: Eligible patients with pelvic inflammatory disease were randomized to receive either ampicillin-sulbactam or cefoxitin (2 g every 6 hours) plus doxycycline (100 mg every 12 hours). Those with endometritis were randomized to ampicillin-sulbactam or clindamycin (900 mg every 8 hours) plus gentamicin (1.5 mg/kg every 8 hours). In the ampicillin-sulbactam group, chlamydia-positive patients also received oral doxycycline. Results: For pelvic inflammatory disease, the clinical response rates (cure or improvement) were 85.5% (47 of 55) and 89.6% (43 of 48) in the ampicillin-sulbactam and cefoxitin and doxycycline groups, respectively (χ²=0.10, P=.76). For endometritis, the clinical response rates were 88.7% (141 of 159) and 90.8% (139 of 153) in the ampicillin sulbactam and clindamycin and gentamicin groups, respectively (χ²=0.15, P=.70). The percentages of patients with pelvic inflammatory disease who had adverse experiences were not significantly different in the cefoxitin and doxycycline group (47% [29 of 62]) than in those receiving ampicillin-sulbactam (33% [22 of 66]) (P=.12). These adverse effects were mostly mild or moderate. In the endometritis subjects, the incidence of adverse experiences in the ampicillin-sulbactam group (11% [20 of 179]) was comparable to that during treatment with clindamycin and gentamicin (12% [22 of 180]). These adverse experiences were also mostly mild to moderate. Conclusion: Ampicillin-sulbactam is as effective and well tolerated as combination regimens using cefoxitin plus doxycycline and clindamycin plus gentamicin for the treatment of pelvic inflammatory disease or endometritis, respectively.