Microbial flora in ileal and colonic neobladders

Area of Science:

• Urology
• Microbiology
• Surgical Reconstruction

Background:

• Urinary tract reconstruction using intestinal segments (ileal or colonic neobladders) is a common procedure after radical prostatectomy.
• Understanding the microbial environment within these neobladders is crucial for patient outcomes and preventing complications.

Purpose of the Study:

• To characterize the bacterial colonization patterns in patients with ileal and colonic neobladders.
• To investigate the correlation between bacterial colonization, residual urine, and urinary leakage.
• To assess the impact of prophylactic antibiotic therapy on neobladder bacteriuria.

Main Methods:

• Urine cultures were performed weekly for 3 weeks and again at 6 months in patients with ileal neobladders, colonic neobladders, post-radical prostatectomy, and healthy controls.
• Residual urine volume and urinary leakage were assessed.
• A subset of ileal neobladder patients received prophylactic trimethoprim.

Main Results:

• Neobladders showed high rates of bacterial colonization (67%), including uropathogenic species, unlike controls and prostatectomy patients.
• Bacterial colonization strongly correlated with increased residual urine but not with leakage.
• Ileal neobladders had higher rates of anaerobic colonization compared to colonic neobladders.

Conclusions:

• The lower urinary tract in neobladder patients is heavily colonized by potentially uropathogenic and anaerobic bacteria.
• Complete bladder emptying significantly reduces the bacterial burden.
• Prophylactic antibiotics did not reduce bacterial burden but altered the microbial composition, favoring anaerobic strains.