[Urethral microbiome in patients with pulmonary tuberculosis]

Treatment of tuberculosis involves long-term intake of several antimicrobial drugs, including that with a wide spectrum of action, which may affect the microflora of the urinary tract.

To determine the effect of long-term combination of antibiotic drugs on the microbiome of male urethra.

A total of 75 men were included in an open, prospective, non-comparative study, including 63 patients with pulmonary tuberculosis who received anti-tuberculosis therapy for at least 3 and no more than 5 months without urinary tract infections (main group) and 12 patients with non-infectious urological diseases (urolithiasis, benign prostatic hyperplasia) and normal urinalysis (comparison group). All patients underwent urethral swab with a sterile cotton after cleaning of genital area. The identification of pathogens and the quantitative assessment of composition of the microbiota in the obtained samples was performed by the method of real-time polymerase chain reaction (RT-PCR). The quantitative results are presented in the number of genomic equivalents in 1 ml (GE/ml), which are proportional to the microbial contamination of the samples.

"Classical" pathogenic microflora in the urethral swab was detected in 1/3-1/4 patient with tuberculosis. Enterobacteriaceae spp./Enterococcus spp. in a titer of 103-104 GE/ml was identified in 16 (25.4%) patients. Staphylococcus spp. was found in the titer of 103-106 GE/ml in 20 males (31.7%). In the comparison group, Staphylococcus spp. was present in half of the cases (n=6), and Enterobacteriaceae spp./ Enterococcus spp. were isolated in every third patient (n=4) with a titer of 103-105 GE/ml. In patients with tuberculosis, Corynebacterium spp. was most commonly detected (n=31, 49.2%), while in the comparison group this pathogen was isolated only in 3 (25.0%) patients. At the same time, the detection rate of Candida spp. in urethral swab was not significantly different between two groups (7.9 and 8.3%, respectively).

Patients with tuberculosis receiving combination of chemotherapeutic drugs for at least 3 months, and male without signs of urinary tract infections have significant differences in the spectrum of the urethral microflora.