The role of fluoroquinolones in sexually transmitted diseases

The management of sexually transmitted diseases (STDs) has reached a new level in the era of antibiotic resistance and human immunodeficiency virus infection. To date, no single antimicrobial is capable of eradicating the commonly encountered STD pathogens including Neisseria gonorrhoeae, Chlamydia trachomatis, and Treponema pallidum. Among the marketed fluoroquinolones, ciprofloxacin, ofloxacin, lomefloxacin, and enoxacin all provide excellent in vitro activity (MIC90 < 0.06 micrograms/ml) and excellent in vivo efficacy against N. gonorrhoeae, including multiply resistant isolates (penicillinase-producing N. gonorrhoeae and chromosomally mediated resistant N. gonorrhoeae). Ofloxacin is the only fluoroquinolone approved by the Food and Drug Administration for chlamydial infection. All of the quinolones lack reliable in vitro activity against Ureaplasma urealyticum, a cause of nongonococcal urethritis. Although limited data suggest the usefulness of ciprofloxacin and ofloxacin in the treatment of pelvic inflammatory disease, these drugs cannot currently be recommended for single-agent therapy. Haemophilus ducreyi infections, however, can be managed effectively with the fluoroquinolones. Although their role continues to evolve, this class of drugs cannot be used equally to treat all STDs, and notably, no quinolone to date inhibits T. pallidum.