Association of Mycoplasma genitalium with nongonococcal urethritis in heterosexual men

Chlamydia trachomatis and Neisseria gonorrhoeae are universally acknowledge d as urethral pathogens, yet the etiology in the majority of cases of ureth ritis is unclear. Our case-control study assessed the association of Mycopl asma genitalium, Ureaplasma urealyticum, and other potential pathogens with acute nongonococcal urethritis (NGU) in heterosexual men presenting to an urban sexually transmitted diseases clinic. M. genitalium was detected in 2 7 (22%) of 121 NGU case patients and in 5 (4%) of 117 control subjects (P<. 01). Although C. trachomatis was detected in 36 (30%) of 121 NGU case patie nts and in 4 (3%) of 117 control subjects (P <.01), only 3 men with NGU wer e infected with both C. trachomatis and M. genitalium. U. urealyticum was n ot associated with NGU. By multivariate analyses, controlling for age, race , history of prior urethritis, and chlamydial infection, M. genitalium was associated with a 6.5-fold increased risk of urethritis (95% confidence int erval, 2.1-19.5), which supports a role of this organism in the etiology of NGU.