Virusuria as a component of the urine microbiota and its significance for assessing the health of the urinary tract: a descriptive clinical study

Aim. To determine the frequency of occurrence of opрortunistic pathogenic bacterial flora and viral pathogens in the urine of healthy people with the establishment of the association between them. Materials and methods. 40 healthy sexually active women and men were examined, which are divided by gender into equivalent groups: Group I - healthy women (n=19), Group II - healthy men (n=21). The age of the subjects ranged from 20 to 25 years, the average age was 22.4±1.2 years. In both groups, the average portion of morning urine was taken for a study after a proper hygienic procedure with self-urination of the subjects in a sterile plastic container (Sterile Uricol for urine sample collection «HiMedia»). In addition to the nutrient media regulated by the Clinical Guidelines, additional HiMedia chromogenic media were used to cultivate facultative anaerobic (FAB) and non-clostridial anaerobic bacteria (NAB). Detection of viruses was performed by PCR with detection in «real time». DNA isolation was carried out by the sorption method using the AmpliPrime DNA-Sorb-B («NextBio») kit from urine samples, with preliminary concentration. Results. In all 40 cases, normative leukocyturia was detected in the urine. According to the results ofbacteriological examination ofurine, healthy men and women in all cases found aerobic-anaerobic associations. Coagulase-negative staphylococci (CNS) and Corynebacterium spp. Dominated in the cluster of aerobic taxa of microbiota. (75.0%, 55.0% respectively). The spectrum of CNS was represented by five species: S.epidermidis (30.0%), S.haemolyticus (27.5%), and S.warneri (25.0%), S.saprophyticus and S.lentus (15.0%). Enterococcus spp. were recorded in the urine in 32.5% of cases. Representatives of the Enterobacteriaceae family were represented by 4 taxa: E. coli (10.0%), Klebsiella spp., Proteus spp. (5.0% each), Enterobacter spp., Citrobacter spp. (2.5%). In a cluster of anaerobic bacteria in the urine, Eubacterium spp. (60.0%) and almost half of healthy individuals recorded Lactobacillus spp. and Peptococcus spp. (42.5% each). When analyzing the frequencies of detection of various microbiota taxa, it was found that women significantly more frequently recorded urine Corynebacterium spp., Eubacterium spp. and Lactobacillus spp., as well as Enterococcus spp. and Peptococcus spp. Peptostreptococcus spp. and Veillonella spp. were significantly more often determined (p<0.05) in the urine of men. HHV6 (10.0%), HPV18 and B19 parvovirus (2,5%) were determined in the urine of healthy people. It should be noted that the studied viruses were more often recorded in men, in particular, HPV18 and parvovirus B19 - only in men, and HHV6 - more often in men (7.5%), less often in women (2.5%). Significant associations of some genera of microorganisms with the sex of the participants were revealed for E. faecalis and Lactobacillus spp., which were more often found in the urine of healthy women Reliably significant associations were found for three taxa: viruses HPV6, HPV18 and parvoviruses B19 (16.7%) were determined in the presence of Bacteroides spp., Bifidobacterium spp., and Prevotella spp., in urine. Accordingly, in 83.3% of cases, these viruses were detected in the absence of the above-listed taxa of microorganisms in the urine. Conclusions. The normal urinary microbiota of healthy women and men has differences: Lactobacillus spp and Candida spp are absent in the urine of men while Streptococcus spp in urine of women. HHV6, HPV18, parvoviruses B19 are found in urine of healthy people and more often in men. Data about the virobiota and microbiota of urine in healthy people can highlight on the pathogenesis of urinary tract infections of various localization and develop targeted approaches in personalized therapy of this group of diseases.

virobiota, microbiota, metagenomic sequencing, urine culture