Treatment of concomitant Neisseria gonorrhoeae and Chlamydia trachomatis infections in women: comparison of trimethoprim-sulfamethoxazole with ampicillin-probenecid.

Sixty-nine women with known or suspected uncomplicated gonorrhea were treated randomly either with a single dose of 3.5 g of ampicillin plus 1 g of probenecid or with four doses of trimethoprim-sulfamethoxazole (TMP-SMZ) in two double-strength tablets (160 mg of TMP plus 800 mg of SMZ) twice daily for two days. Overall, 56 (81%) of the women had gonococcal infections, 26 (38%) had chlamydial infections, and 23 (33%) had coexisting Chlamydia trachomatis and Neisseria gonorrhoeae infections. Among the women with genital or anal gonorrhea, two (9%) of 23 treated with TMP-SMZ and three (12%) of 25 treated with ampicillin and probenecid remained infected. TMP-SMZ cured four of four pharyngeal gonococcal infections. C. trachomatis was isolated at the first posttreatment visit significantly more often after treatment with ampicillin and probenecid (10 of 11 times) than after treatment with TMP-SMZ (1 of 10 times; P = 0.003). However, at the second follow-up visit, C. trachomatis was isolated from 30% of the women treated with TMP-SMZ. The area of ectopic columnar epithelium (ectopy) on the ectocervix and edema of this area were highly correlated with the presence of C. trachomatis, and persistence of C. trachomatis was associated with persistent edema of ectopy and with friability. TMP-SMZ is as effective as ampicillin-probenecid for the treatment of uncomplicated genital gonorrhea in women and may be more effective for the treatment of pharyngeal gonorrhea. The optimal dose and duration of TMP-SMZ therapy for C. trachomatis infection requires further study.