Impact of Type and Duration of Oral Antibiotic Prophylaxis on Urinary-Tract Infection Rate After Botox.

[INTRODUCTION AND HYPOTHESIS] Urinary tract infection (UTI) is common after onabotulinumtoxin A intradetrusor injections (BTX) but no evidenced-based recommendations exist to guide prophylactic antibiotic regimen. We sought to compare the effect of different oral antibiotic prophylaxis in women with idiopathic and neurogenic overactive bladder (OAB) undergoing BTX.

[METHODS] This was a single-center retrospective cohort study of women >18 years old who underwent BTX for OAB between June 2018 and June 2023. Duration and type of antibiotic prophylaxis at time of BTX injection were recorded. Primary outcome was treatment for symptomatic UTI within 30 days.

[RESULTS] A total of 1250 procedures were included. UTI rate within 30 days of BTX injection was 10% (n = 125). Duration of antibiotics (1 day, 3 days, 5 days, versus ≥7 days of treatment) did not affect 30-day UTI rate (p = 0.42). When comparing antibiotic type, nitrofurantoin had the lowest UTI rate at 8.7% while trimethoprim/sulfamethoxazole (TMP-SMX) had a rate of 12.3% and "other" had highest at 32.4% (p< 0.01). Retreatment rate for UTI was low at 1.9% and urine cultures showed low resistance rates (1.8%) but TMP-SMX had the highest rate of resistance at 4.6% (p < 0.01). There were no differences in retreatment rate or resistance rate between the different durations of prophylactic antibiotics (p>0.05 for both).

[CONCLUSIONS] The UTI rate after onabotulinumtoxin A injections was similar regardless of the duration of prophylactic antibiotic use. Nitrofurantoin and TMP-SMX had the lowest 30-day UTI rates. These data provide compelling evidence in support of 1-day prophylactic antibiotic treatment regimens with nitrofurantoin (or TMP-SMX) for women with OAB undergoing BTX injection.