The Challenge of Asymptomatic Bacteriuria and Symptomatic Urinary Tract Infections in Patients with Neurogenic Lower Urinary Tract Dysfunction

Purpose: We investigated the prevalence of asymptomatic bacteriuria and the incidence of symptomatic urinary tract infections in patients with neurogenic lower urinary tract dysfunction undergoing urodynamics. We also assessed predictors of symptomatic urinary tract infections. Materials and Methods: We evaluated a prospective consecutive series of 317 patients, including 106 women and 211 men, with neurogenic lower urinary tract dysfunction. Of the patients 111 (35%) voided spontaneously, 141 (44%) relied on intermittent self-catheterization and 65 (21%) relied on an indwelling catheter. Before urodynamics the urine samples were collected by sterile catheterization for dipstick testing and urine culture. We assessed the association of patient characteristics with symptomatic urinary tract infections after urodynamics in patients with asymptomatic bacteriuria and developed a prediction model based on the most important risk factors. Results: Before urodynamics urine cultures were negative in 123 patients (39%) and positive in 194 (61%). Escherichia coli and Klebsiella pneumoniae were the most frequent bacteria, found in 32% and 18% of patients, respectively. Of 194 patients with a positive culture 35 (18%) had at least 1 symptomatic urinary tract infection. In patients with a history of previous urinary tract infections the overall estimated probability of a symptomatic urinary tract infection was 45% regardless of the underlying neurological disorder. Conclusions: A symptomatic urinary tract infection will develop in the follow-up year in about 1 of 5 patients with asymptomatic bacteriuria. This rather low overall probability precludes routine antibiotic prophylaxis or treatment in patients with neurogenic lower urinary tract dysfunction who have asymptomatic bacteriuria since 4 of 5 would be overtreated. However, in patients with a history of previous symptomatic urinary tract infections antibiotic prescription might be justified.