Botox rechallenge-An additional tool in the management of an incompletely emptying bladder and inadequate overactive symptom control following sacral neuromodulation.

Two female patients aged 70 and 72 with video-urodynamics-confirmed detrusor overactivity and detrusor underactivity (DO-DU) were treated. Patients were refractory to medical therapies and had previously failed intravesical botulinum toxin type A (BoNT-A) at other centers secondary to urinary retention and difficulty with self-catheterization. Placement of an Interstim II device (Medtronic, Minneapolis, Minnesota) for sacral neuromodulation (SNM) as alternative third-line treatment partially improved overactive bladder (OAB) symptoms while significantly improving voiding symptoms. Postvoid residual (PVR) of patients improved from a median of 118 mL (110-125 mL) to 20 mL (18-26 mL) and 213 mL (195-230 mL) to 70 mL (60-73 mL), respectively. Addition of medical therapies post SNM failed to modify OAB symptoms further and a rechallenge with dose-reduced BoNT-A was undertaken.OAB symptoms were significantly improved by addition of BoNT-A, while urinary retention was avoided (median PVR post BoNT-A 38 mL [34-40 mL] and 185 mL [150-205 mL], respectively). Reduction in incontinence pad use as well as resolution of nighttime incontinence in both patients and daytime incontinence in one patient was achieved. DO-DU patients treated by SNM who have improved bladder emptying (PVR <100 mL) but incomplete resolution of OAB symptoms should be trialed on adjunct medical therapies to improve OAB symptoms. If OAB symptoms are still inadequately controlled, consideration of a rechallenge with BoNT-A, particularly with dose reduction, appears to be efficacious and avoids symptomatic retention in this challenging cohort.