The effect of ciprofloxacin and doxycycline plus metronidazole on lower genital tract flora in patients with proven pelvic inflammatory disease.

Alterations in the lower genital tract flora were studied during antimicrobial treatment of 36 women with acute pelvic inflammatory disease (PID). Sixteen women received ciprofloxacin, and 20 received doxycycline plus metronidazole. Both regimes eradicated Chlamydia trachomatis in all cases and Neisseria gonorrhoeae in all except one in which combination treatment failed because of resistance of the organism to tetracycline. Both regimes eradicated Mycoplasma hominis in all cases, while ciprofloxacin was somewhat less effective than combination treatment against Ureaplasma urealyticum. Ciprofloxacin was less effective than combination treatment against Gardnerella vaginalis. The incidence of Candida infection increased equally in both groups, although symptoms necessitating antifungal treatment were rare.