Pelvic inflammatory disease (PID) affects 4.4% of women aged 18-44 in the United States, and may cause infertility if it is ineffectively treated. A combination of clindamycin and gentamicin is generally used for the treatment of PID. The benefit of adding metronidazole into the treatment combination still remains unclear, and this study was designed to evaluate its effectiveness. We retrospectively included 107 women who were diagnosed with PID from May 2013 to September 2020 in a single hospital. Based on their used antibiotic regimens, the patients were divided into three groups-those who were treated with clindamycin + gentamicin (group 1, n = 46), those who took regular antibiotics plus metronidazole (group 2, n = 27), and others (group 3, n = 34). Primary outcomes included the rates of taking surgery after failed antibiotics, occurrence/rupture of tubo-ovarian abscesses, and readmission within the following 6 months of first treatment. Secondary outcomes to assess were the length of stay (LOS) and expenditure for PID. There were no significant differences in the surgical rates, readmission rates, LOS and expenditure noted between the three groups. Subgroup analysis showed that visual analogue pain scores being 5 or more would increase the LOS by 3.83 days (p < 0.001), and body temperature > 38.3 °C or more would increase the treatment total expenditure (p < 0.001). Our study results suggest that the combination of clindamycin + gentamicin is a convincible treatment protocol for PID.
Keywords: clindamycin; gentamicin; metronidazole; pelvic inflammatory disease.