Introduction Chlamydia trachomatis, Mycoplasma genitalium or Trichomonas vaginalis are the pathogens for non-gonococcal urethritis, but pathogenicity of other microorganisms for the male urethral has not be confirmed. In this study, the bacterial flora of urine specimens from male patients with urethritis was analysed by the clone library method based on the 16S rRNA gene.

Methods The first voided urine specimens of male patients with urethritis were collected. The detection of Neisseria gonorrheae, C.trachomatis were examined by transcriptional mediated amplification (TMA) method and M. genitalium, Ureaplasma urealyticum, Ureaplasma parvum and Mycoplasma hominis were examined by real-time PCR method. The urine specimens were strained by Ethidium bromide and the number of bacterial cells were counted. DNA was extracted from the urine and amplification of the 16S rRNA gene via PCR (universal primers) and determination of the nucleotide sequences of 96 colonies were performed. The homology search was performed with a basic local aligment search tool (BLAST) using in-house software system and phylotypes of bacteria in each specimens were analysed.

Results Urine specimens were collected from 58 patients and the divided to 4 group; gonogoccal urethritis (n:9), chlamydial urethritis (n:12), non-chlamydial non gonococcal urethritis detecting with Ureaplasmas or Mycoplasmas (UM+NCNGU, n;15) and non-chlamydial non gonococcal urethritis detecting without Ureaplasmas or Mycoplasmas (UM-NCNGU, n:22). Cell numbers were higher in UM+NCNGU than in UM-NCNGU. Among specimens, 2427 clones in 38 bacterial flora could be analysed and 91 bacterial phylotypes were detected together with N.gonorrhoeae, C.trachomatis, Mycoplasmas or Ureaplasmas positive specimens among chlamydial urethritis or UM+NCNGU groups. Gardnerella vaginalis was detected with Mycoplasma/Ureaplasma in Chlamydial urethritis ot UM+NCNGU.

Conclusion The clone library method by using 16S rRNA gene is the new technology for analysis the bacterial flora of urine with urethritis. The relationship between G. vaginalis and Ureaplasma/Mycoplasma was found by this analysis.

Disclosure of interest statement This study was supported by Japan Society for Promotion Science (JSPS) KAKENHI Grant Number 25293337.