Does asymptomatic bacteriuria affect the response to intravesical bacillus Calmette-Guérin?

To determine the initial response to intravesical bacillus Calmette-Guérin and the 3-year recurrence rate of high-risk non-muscle-invasive bladder cancer in patients who have asymptomatic bacteriuria.

Response and recurrence rates were investigated in 505 patients with high-risk non-muscle-invasive bladder cancer after treatment with induction bacillus Calmette-Guérin (TICE strain) therapy. Initial response was determined after 3 months and patients were followed every 3-6 months for 3 years. Before bacillus Calmette-Guérin and each follow-up cystoscopy, urine cultures were obtained, stratified as no growth, <104, >104 or >105 colony-forming unit/mL. Any degree of bacteriuria on culture was classified as asymptomatic bacteriuria.

Of the 505 cases, 270 (53%) had asymptomatic bacteriuria. A total of 89% of patients with asymptomatic bacteriuria showed a complete response to bacillus Calmette-Guérin versus 76% of uninfected patients (P = 0.001), and 75% of bacteriuric patients survived tumor-free for 3 years versus 65% of uninfected patients.

Chronic bacteriuria might enhance the response of high-risk non-muscle-invasive bladder cancer to intravesical bacillus Calmette-Guérin and result in longer tumor-free survival than uninfected patients.