On the assesment of the etiological significance of bacteria detected in the male genital tract

Abstract

Introduction. Currently, there is an increasing importance of microbial associations in the pathogenesis of genital inflammatory diseases. However, the issues of deciphering the taxonomic affiliation and the diagnostic significance of the bacteria detected in this case remain unresolved. The aim of the study was to review the diagnostic significance of the quantitative approach in determining the etiological role of microorganisms in andrology. Materials and methods. For the study, samples of ejaculate and/or discharge from the urethra from 15 men who were in infertile marriages, 12 with a confirmed diagnosis of "acute genital gonococcal infection" were used. The testing included a classic bacteriological study and the metagenomic analysis of 16S ribosomal RNA samples carried out at the Department of Collection Cultures of the State Research Center for Applied Microbiology (Obolensk). To standardize the distribution of samples into groups based on the indicators of alpha diversity and the concentration of putrescine, the range of variation and the average linear deviation were used. Statistical analysis of the obtained data was carried out using Excel software (MS Office package). Results. The microbial landscape of the ejaculate was characterized by the predominance of representatives of the genera Enterococcus, Neisseria, Lactobacillus, Corynebacterium, Prevotella, Bacteroides. Stable associations of E. faecalis and M. osloensis were detected in the ejaculate. When using the cultural method, representatives of the genus Moraxella were not isolated in any sample. It was shown that discrepancies can affect not only quantitative indicators, but also reveal inconsistencies between the qualitative assessment of detected genetic markers and the results of identification in a bacteriological study of individual representatives of similar or phenotypically similar taxa. Discussion. The results of this study indicate that the lesser diversity of opportunistic pathogens gives them more opportunities to realize their pathogenic potential. On the other hand, in a complex community with greater alpha diversity, its realization is hindered by a complex intermicrobial relationships and the need to survive. Conclusion. As a result, it seems that the most promising approach is the integrated use of cultural methods and metagenomics with a comparative statistical analysis of the obtained qualitative and quantitative indicators.

Keywords

• microbial community
• cultivation
• metagenomic research
• polyamines