Quantitative detection of Mycoplasma genitalium from first-pass urine of men with urethritis and asymptomatic men by real-time PCR.
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 phylogeny-based assay. Of 130 men with gonococcal urethritis (GU), five were positive for M. genitalium. The mycoplasma load for each specimen was <5 x 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 x 10 copies/ml, and six men had loads ranging from 1.1 x 10(7) to 2.7 x 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 x 10(6) to 2.3 x 10(2) copies/ml. Of 76 asymptomatic men, only two were positive for M. genitalium. For these men, the loads were 2 x 10(2) and <5 x 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.
Yoshida
Takashi
T
Research and Development Department, Mitsubishi Kagaku Bio-Clinical Laboratories, Inc., Tokyo 174-8555, Japan.
Deguchi
Takashi
T
Ito
Masayasu
M
Maeda
Shin-Ichi
S
Tamaki
Masayoshi
M
Ishiko
Hiroaki
H
D004269:DNA, Bacterial / Q000032:analysis; D020459:Genes, rRNA; D006801:Humans; D008297:Male; D009174:Mycoplasma / Q000235:genetics / Q000302:isolation & purification* / Q000472:pathogenicity; D009175:Mycoplasma Infections / Q000382:microbiology; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D019914:Taq Polymerase / Q000378:metabolism; D014526:Urethritis / Q000382:microbiology*; D014556:Urine / Q000382:microbiology*
D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D019914:Taq Polymerase