Urodynamic risk factors of asymptomatic bacteriuria in men with non-neurogenic lower urinary tract symptoms

Purpose To investigate the prevalence of asymptomatic bacteriuria (ASB) in middle-aged and older men with non-neurogenic lower urinary tract symptoms (LUTS) and clarify urodynamic factors related to the presence of ASB. Methods We retrospectively reviewed the clinical data of men with LUTS who underwent urine culture examination, LUTS severity assessment, and urodynamic studies. The patients were allocated into two groups (the ASB + LUTS and LUTS-only) according to presence or absence of ASB. The patients’ characteristics and urodynamic factors related to the development of ASB were assessed using univariate, binomial logistic regression, and receiver-operating characteristic (ROC) curve analyses. Results Of 440 men, 93 (21.1%) had ASB. Parameters related to voiding functions, such as maximum flow rate, post-void residual urine volume, bladder voiding efficiency (BVE), and bladder contractility index (BCI), were significantly reduced in the ASB + LUTS group, while bladder outlet obstruction index was not different between the groups. Binomial logistic regression analysis showed that the presence of diabetes, lower BCI, and lower BVE were significantly associated with the presence of ASB. In addition, ROC analysis identified 55% as the optimal cutoff value of BVE for the presence of ASB, with a sensitivity of 84% and specificity of 83%. Conclusions ASB was found in > 20% of men with non-neurogenic LUTS and was associated with decreased bladder contractility and decreased BVE. BVE could predict presence of ASB with high sensitivity and specificity.