Neurogenic lower urinary tract dysfunction (NLUTD) in children can cause renal failure and urinary incontinence if not treated sufficiently. Antimuscarinics (AM) and intradetrusor botulinum toxin injections (BoNT-A) with clean intermittent catheterization (CIC) are widely used treatment options for children with NLUTD. However, a considerable number will become refractory to these treatment options. This study aimed to evaluate the efficacy and long-term outcomes of mirabegron in children with NLUTD as an add-on and as a stand-alone treatment.
Patients under 18 years of age with NLUTD who were refractory to AM and/or BoNT-A and were treated with mirabegron 50 mg were retrospectively studied. Mirabegron was either used as monotherapy or in addition to AM and/or BoNT-A. Video-urodynamic studies (VUDSs) were performed before and after treatment with mirabegron. Changes in video-urodynamic parameters, the need for other NLUTD therapy during follow-up, patient-reported side effects, and urinary incontinence were outcomes of interest.
A total of 34 patients with NLUTD were included. All patients were on CIC and the median age was 13.1 years (IQR 15.9-10.3). Median follow-up was 31.4 months (IQR 57.4-11.4). Bladder compliance improved by 89.9%, from 14.9 to 28.3 ml/cm H2O (p-value<0.001). Maximum cystometric capacity, end-filling detrusor pressure, volume at first detrusor overactivity, vesicoureteral reflux, and urinary incontinence significantly improved after mirabegron. The add-on therapy group showed more significant improvements in video-urodynamic outcomes compared to the monotherapy group. The median time of requiring other NLUTD therapy was 25.5 months (IQR 39.8-14.8). None of the included patients reported side effects.
Mirabegron is an effective treatment for children with therapy-refractory NLUTD with an average efficacy of 2 years after which additional therapy is required. Despite the retrospective character of this study, our results confirm the beneficial effect of mirabegron in children with therapy-refractory NLUTD, in particular when mirabegron is used as add-on therapy in those with low-compliance bladders.
Journal of pediatric urology. 2023 Aug 19 [Epub ahead of print]
Felice E E van Veen, Martje Schotman, Lisette A 't Hoen, Bertil F M Blok, Jeroen R Scheepe
Department of Urology and Pediatric Urology, Sophia Children's Hospital, Erasmus MC, Rotterdam, the Netherlands. Electronic address: ., Department of Urology and Pediatric Urology, Sophia Children's Hospital, Erasmus MC, Rotterdam, the Netherlands.