BACKGROUND

Currently, no recognized evidence is known about the bacterial communities found within seminal vesicles (SV) of men presenting with refractory hematospermia.

METHODS AND RESULTS

Fifteen male patients with refractory hematospermia or anejaculation were enrolled, and 15 SV-Infection (SV-In) samples from SV with hemorrhage and/or stones, 11 SV-Control (SV-C) samples from SV with non-infection, and 14 Urine (Urine) samples from posterior urethra were obtained via transurethral seminal vesiculoscopy. Then the high-throughput 16 S rRNA gene sequencing method was performed to characterize the microbiota profile. Finally, a total of 1535 operational taxonomic units (OTUs) were found, 1295 OTUs were shared across three groups, 7 OTUs, 45 OTUs, and 48 OTUs were unique to SV-C group, SV-In group, and Urine group, respectively. The 5 top bacterial phyla (mean relative abundance) in all samples were Firmicutes (52.08%), Bacteroidetes (21.69%), Proteobacteria (12.72%), Actinobacteria (9.64%), and Fusobacteria (1.62%), the 5 top bacterial genera in all samples were Bacteroides (9.13%), Lactobacillus (5.38%), Bifidobacterium (5.35%), Faecalibacterium (5.10%), and Allobaculum (3.34%), of which Bifidobacterium had the highest level in SV-C samples and had a significant difference (P < 0.05) across all groups. Differential analysis showed genera Leuconostoc and LachnospiraceaeFCS020group were identified as biomarkers in the SV-In microbiota.

CONCLUSION

Altered microbiota composition in seminal vesicles is related to refractory hematospermia in men, and the distribution of genus Leuconostoc or LachnospiraceaeFCS020group within seminal vesicles may interact with hematospermia. This study provides clues for the diagnosis and treatment of this urologic disorder.