Our results showed a significant association between U. urealyticum (biovar 2) and NGU. They also suggest that the presence of U. parvum (biovar 1) in the male urethra might be the result of colonization.

No abstract

We developed a TaqMan-based real-time PCR assay for quantifying Mycoplasma genitalium. This assay is able to specifically quantify concentrations of the M. genitalium 16S rRNA gene ranging from 10 7 to 10 copies/reaction. Using the TaqMan assay, we quantified the M. genitalium 16S rRNA gene in first-pass urine of men with urethritis and asymptomatic men who were positive for M. genitalium by PCR-and phylogenybased assay. Of 130 men with gonococcal urethritis (GU), five were positive for M. genitalium. The mycoplasma load for each specimen was <5 ؋ 10 copies/ml. Of 84 men with chlamydial non-GU (CNGU), seven were positive for M. genitalium. One man had an M. genitalium load of <5 ؋ 10 copies/ml, and six men had loads ranging from 1.1 ؋ 10 7 to 2.7 ؋ 10 2 copies/ml. Of 86 men with nonchlamydial NGU (NCNGU), 17 were positive for M. genitalium. The mycoplasma loads for these men ranged from 3.3 ؋ 10 6 to 2.3 ؋ 10 2 copies/ml. Of 76 asymptomatic men, only two were positive for M. genitalium. For these men, the loads were 2 ؋ 10 2 and <5 ؋ 10 copies/ml. The patients with NGU had significantly higher concentrations of M. genitalium in their first-pass urine than did men with GU (P < 0.01) or asymptomatic men (P < 0.05). In addition, M. genitalium loads were significantly higher in men with NCNGU than those in asymptomatic men (P < 0.05). The quantitative assessment of M. genitalium loads by the TaqMan assay will provide useful information for understanding the pathogenicity of this mycoplasma in the urogenital tract.Mycoplasma genitalium was isolated in urethral cultures from two men with nongonococcal urethritis (NGU) in 1981 (21). Although M. genitalium had been proposed as a cause of human NGU (22), the precise role of the mycoplasma in the etiology of NGU had not been established because of the immense difficulty in isolating it from clinical samples. Since PCR-based assays facilitated the detection of M. genitalium in clinical specimens (10, 17), a significant association between M. genitalium and NGU has been demonstrated (7,9,13,20). So far, however, any studies to investigate the potential association of M. genitalium loads with the pathogenicity of the mycoplasma in the urogenital tract have not been performed, because isolation of M. genitalium in culture is still difficult and because conventional PCR-based assays are lacking in quantitative assessment of the mycoplasma in clinical specimens. For this study, therefore, we developed a TaqMan-based real-time PCR assay for quantifying M. genitalium. Using this assay, we quantified M. genitalium DNA in first-pass urine of men with urethritis and asymptomatic men and assessed whether the bacterial load of M. genitalium might be associated with the pathogenicity of the mycoplasma in the urogenital tract. MATERIALS AND METHODS Bacterial strains. Strains of 15 species of human mycoplasmas and ureaplasmas, including Mycoplasma buccale, Mycoplasma faucium, Mycoplasma fermentans, M. genitalium, Mycoplasma hominis, Mycoplasma lipophilum, Mycoplasmaorale, Mycoplasma pene...

This study suggests that the persistence of M genitalium in the urethra may be associated with recurrence of nongonococcal urethritis.

The association of increased U. urealyticum (biovar 2) loads with symptomatic urethritis suggests that U. urealyticum (biovar 2) may be a pathogen of NGU. Our results also suggest that the presence of U. parvum (biovar 1) may not be significant in the development of NGU.

Coinfection with M. genitalium or U. ureaplasma biovar 2 in men with GU was significantly associated with PGU, independent of C. trachomatis. Men with GU should be treated presumptively with antibiotics that are active against C. trachomatis, M. genitalium, and U. urealyticum biovar 2.

The prevalences of M. genitalium in patients with gonococcal urethritis and nongonococcal urethritis who attended our clinic were 4.1 and 13.2%, respectively. M. genitalium was detected significantly more often in men with nongonococcal urethritis than in asymptomatic men. In addition, its prevalence in men with chlamydia negative nongonococcal urethritis (26.5%) was significantly greater than in those with chlamydia positive nongonococcal urethritis (2.4%). These findings suggest that M. genitalium may be associated with the development of nongonococcal urethritis independent of C. trachomatis.

This study suggests that subtype 1 of U. urealyticum (serovars 2, 5, 8, and 9) is associated with NGU independently of Chlamydia trachomatis or M. genitalium.