[Evaluation of the composition of the microbiota of the urethra in men with sexually transmitted infections]

Abstract

Objective: to conduct a comparative study of the composition of the microbiota of the urethra in men with sexually transmitted infections (STIs), and healthy men.

Material and methods: The study included 103 men aged 18 to 45 years: 42 men with urethritis caused by STIs and 61 clinically healthy men. Identification of pathogenic and conditionally pathogenic microorganisms in scrapings from the urethra was performed by PCR in real time (test system Androflor (DNA-Technology, Moscow).

Results: In the analysis of the total bacterial mass, it was found that the bacterial contamination of the urethral biotope in patients with STI was significantly higher than in the group of healthy men (5.8 Lg10 and 4.7 Lg10, respectively), with the highest level of bacterial contamination was detected in patients infected with N. gonorrhoeae (6.4 Lg10). Patients with STIs had significantly lower levels of relative Staphylococcus spp., Streptococcus spp., Corynebacterium spp. and their amounts in General compared to clinically healthy men: according to ROC analysis, the best diagnostic indicator (0.93+/-0.04, p<0.001), distinguishing a group of healthy individuals from patients with STI, was the amount of Staphylococcus spp., Streptococcus spp. and Corynebacterium spp. ("Amount Of Normoflor"). In patients infected with C. trachomatis, compared with clinically healthy men, the relative number was significantly higher of Bacteroides spp. / Porphyromonas spp. / Prevotella spp., Peptostreptococcus spp. / Parvimonas spp.; in patients infected with N. gonorrhoeae - Anaerococcus spp. and in patients infected with M. genitalium - Megasphaera spp. / Veillonella spp. / Dialister spp., Anaerococcus spp., Peptostreptococcus spp. / Parvimonas spp. and Eubacterium spp.

Conclusion: An increase in the total bacterial contamination of the urethra in STI was found, most pronounced in infection with Neisseria gonorrhoeae. The best diagnostic indicator that distinguishes normal microbiota from the microbiota of patients with STIs is the sum of Staphylococcus spp., Streptococcus spp. and Corynebacterium spp. In patients with clinical signs of an inflammatory reaction and the presence of STIs, a decrease in the normoflora in all types of STIs and an increase in obligate anaerobic bacteria - Megasphaera spp. / Veillonella spp. / Dialister spp., Bacteroides spp. / Porphyromonas spp. / Prevotella spp., Anaerococcus spp., Peptostreptococcus spp. / Parvimonas spp. and Eubacterium spp.

Keywords: STI; real-time PCR; urethral microbiota; urethritis.