Azithromycin treatment for nongonococcal urethritis negative for Chlamydia trachomatis, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum, and Ureaplasma urealyticum.

Some patients with nongonococcal urethritis (NGU) are negative for Chlamydia trachomatis, mycoplasmas, and ureaplasmas. The optimal antimicrobial chemotherapy for such NGU has not fully been clarified. We assessed the efficacy of azithromycin for treatment of nonmycoplasmal, nonureaplasmal, nonchlamydial NGU (NMNUNCNGU). Thirty-eight men whose first-pass urine was negative for Chlamydia trachomatis, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum, and Ureaplasma urealyticum were treated with a single dose of 1 g azithromycin. Urethritis symptoms and polymorphonuclear leukocytes in urethral smears or in first-pass urine were assessed before and after treatment with azithromycin. Thirty-two (84.2%) of the 38 men with NMNUNCNGU showed no signs of urethral inflammation after treatment. The efficacy of this azithromycin regimen was comparable to that of the 7-day regimen of levofloxacin, gatifloxacin, minocycline, or clarithromycin reported previously. A single dose of 1 g azithromycin, which is effective not only for NGU due to specific pathogens but also for NMNUNCNGU, is an appropriate treatment for NGU.