Urinary microbiota is associated to clinicopathological features in benign prostatic hyperplasia.

BACKGROUND: The urinary microbiota of patients with benign prostatic hyperplasia (BPH) has been associated with lower urinary tract symptoms (LUTS), however, little is known about urinary microbiota correlations with clinicopathological parameters associated with BPH. Here, we investigate associations between the urinary microbiota and clinical parameters of patients with BPH undergoing surgery. METHODS: Forty-one patients with BPH undergoing surgery were recruited from two medical centers. Catheterized urine specimens were collected and the microbiota was characterized by 16S rRNA gene sequencing. Patients were segregated into two groups according to each clinical parameter and differences in urinary microbiota diversity and composition were evaluated. RESULTS: Higher prostate weight and prostate-specific antigen (PSA) levels were associated with higher alpha diversity in the urinary microbiota of BPH patients. At the specific microbe level, we found that the greater the prostatic weight, the lower the relative abundance of Streptococcus, while the greater the PSA levels, the higher the abundance of Lactobacillus. Treatment with 5-α-reductase inhibitor was associated with overall urinary microbiota composition, in part due to a higher abundance of Corynebacterium and Anaerococcus in this group. CONCLUSIONS: We demonstrated that the urinary microbiota of BPH patients is associated with clinicopathological features, paving the way for larger studies in which causality between urinary microbiota and BPH can be appropriately explored.

The bladder microbiota is not significantly altered by intravesical BCG therapy.

INTRODUCTION: Bladder microbiota dysbiosis has been associated with several urological disorders. However, dysbiosis markers in bladder cancer have not been identified and little is known about the effect of Bacillus Calmette-Guérin (BCG) intravesical therapy on the bladder microbiota. In this study, we compared the bladder microbiota of patients with non-muscle-invasive bladder cancer (NMIBC) undergoing BCG therapy to nononcological controls. We also longitudinally analyzed the impact of BCG therapy on the bladder microbiota of NMIBC patients and addressed whether bladder microbiota is associated with BCG efficacy. METHODS: We collected catheterized urine samples from males with intermediate/high-risk NMIBC (cancer group, n = 32) or benign prostatic hyperplasia (control group, n = 41). The cancer group also provided urine samples during and after BCG induction. We used 16S rRNA gene sequencing to characterize the bladder microbiota. Bladder microbiota parameters, such as diversity and taxonomic composition, were compared between groups and associated with clinicopathological data and BCG efficacy. RESULTS: We observed no significant differences between the bladder microbiota of NMIBC patients and controls. BCG intravesical instillations did not significantly alter the bladder microbiota of NMIBC patients, and BCG was rarely detected in the bladder during and after BCG therapy. Microbiota diversity and overall composition before BCG induction did not influence disease persistence at 3 months. However, higher abundance of Lactobacillus, Streptococcus, and Cutibacterium in the pre-BCG bladder microbiota was associated with BCG effectiveness. CONCLUSION: We were unable to identify markers of bladder microbiota dysbiosis among male NMIBC patients. Moreover, we demonstrated for the first time using longitudinally collected samples that BCG cannot persist in the bladder microbiota nor significantly alter its diversity and composition. The associations found between bladder microbes and BCG efficacy highlight the potential of microbial-based therapeutic and risk-stratification strategies in the intermediate/high-risk NMIBC setting.