Comparing Prophylactic Antibiotic Protocols in Office-based Periurethral Bulking

Objectives: There is conflicting evidence regarding type and timing of antibiotic administration for periurethral bulking procedures. Patients are screened for urinary tract infections (UTIs) on the day of the procedure; and urinalysis suggestive of UTI may lead to procedure cancelation. The aim of this study is to evaluate two prophylactic antibiotic protocols for periurethral bulking and their impact on UTI rate, procedure cancelation, and rate of procedure-related office phone calls.

Methods: This was a retrospective cohort study evaluating patients undergoing periurethral bulking in a single Urogynecologic office at an academic institution, between May 2022 and January 2024. Initially, the protocol consisted of antibiotic administration two days prior to the procedure for 3 to 5 days in total (Group 1). The protocol was changed in May 2023 when antibiotics were provided on the day of the procedure for 3 to 5 days (Group 2). The antibiotic regimen included nitrofurantoin, or in case of allergies trimethoprim-sulfamethoxazole or ciprofloxacin. Procedures were cancelled if urinalysis on the procedure date was suggestive of UTI (positive leukocytes and nitrites). Records of patients in both groups were reviewed. The primary outcome was procedural cancellations on presentation for periurethral bulking due to suspected UTI. Secondary outcomes included positive urine cultures the day of the procedure, post-procedural UTI within 8 weeks, and number of office phone calls related to the procedure.

Results: 179 records were included in this study, with 90 in Group 1 and 89 in Group 2. Group 1 was on average younger with a greater proportion of non-Hispanic patients when compared to Group 2 (Table 1). Across both cohorts, 96% of patients received nitrofurantoin for 5 days as their antibiotic regimen (Table 2). Two (2.2%) patients in Group 1 presented with positive urinalyses requiring cancellation, compared to 4 (4.5%) patients in Group 2 (p=0.398). All positive urinalyses resulted in positive urine cultures. Patients in Group 1 called the office regarding their antibiotic regimen a mean of 0.98 (± SD 0.42) times compared to 0.16 (± SD 0.37) for those in Group 2 (p < 0.001). In Group 1, 9 (10%) patients developed a UTI within 8 weeks of the procedure, compared to 8 (9%) patients in Group 2 (p=0.818).

Conclusions: There was no statistically significant difference regarding same-day periurethral bulking cancellations between the two antibiotic protocols, with low numbers of cancellations in both cohorts. Additionally, a similar number of patients in this study developed UTIs within the post-procedural period. Patients who received antibiotics prior to the procedure were more likely to call the office regarding the antibiotic regimen. This study suggests that prescribing antibiotics on the day of the procedure may reduce telephone burden without increasing the risk of same-day procedural cancellation or post-procedural UTI.