Background: Intravesical gentamicin instillations have been shown to be a safe, prophylactic measure in reduction of urinary tract infections (UTIs) in patients who intermittently catheterize. This practice is generally low risk with few side effects but has been shown to be associated with increased bacterial resistance to aminoglycosides. Less information is available regarding the effectiveness of normal saline bladder irrigations in reducing UTIs and evaluations for concerns of infections. We hypothesized that normal saline bladder irrigation would be associated with a reduction in the frequency of febrile UTIs and evaluations for suspected infections in patients evaluated in our Spina Bifida clinic. Methods: A retrospective review of patients evaluated in our multidisciplinary Spina Bifida Clinic between 2020 and 2023 was conducted. The number of urine analysis (UA) obtained, UTI’s treated and UTI-related hospitalizations for each patient were abstracted. UAs obtained was used as a surrogate for evaluation for suspected infection. UTI was defined as the presence of urologic symptoms associated with a documented positive culture that was treated by any provider. Patient characteristics were reported as frequencies and proportions for categorical variables and as median and interquartile range (IQR) for continuous variables. Differences in the outcomes between groups (pre- and post-intervention) were determined by the Wilcoxon matched-pairs signed-rank test. Analyses were performed on Stata version 18.0 (StataCorp LLC, College Station, TX, USA). A p-value of <0.05 was considered statistically significant. Results: Twenty-two patients with a median age of 7.5 years old [IQR 5 to 10 years] and a median follow up of approximately 1 year [IQR 0.57 to 2 years] were included in our study. In total, 45% were males, 73% had associated bowel dysfunction, and 86% were on a bowel program. Four patients were on antibiotic prophylaxis. Among the 22 patients, the median number of UTIs decreased from 3 [IQR 2 to 5] to 0 [IQR 0-2] (P=0.001) (Figure 1a.), and median number of febrile UTIs decreased from 1 [IQR 0-2] to 0 [IQR 0-1] (P=0.01) (Figure 1b.). The median number of UAs obtained after the initiation of irrigations decreased, although it was not statistically significant. Conclusions: Intravesical normal saline irrigations significantly reduced the number of febrile UTIs and UTI-related hospitalizations in patients with neurogenic bladder secondary to Spina Bifida who catheterize at our institution. Although it did show a reduction in UAs obtained, this result was not statically significant. Despite limitations by small sample size and the availability of records, our findings highlight the need for prospective studies to confirm the practical use of the normal saline irrigation and compare it to other methods of UTI prevention like oral antibiotics or gentamycin instillations. Additionally, further studies are needed to further define the ideal administration protocol.
