Non-invasive evaluation of botulinum-A toxin treatment efficacy in children with refractory overactive bladder

Abstract

Objective: We aimed to evaluate the efficacy and safety of intravesical onabotulinum toxin A (onaBoNTA) injections for the treatment of children diagnosed with refractory overactive bladder (OAB) by using non-invasive methods.

Methods: A total of 31 pediatric patients with a mean age of 10.2 years received intravesical onaBoNTA injection at the dose of 10 U/kg (max: 200 U). Twenty-one patients who failed to respond to the first injection, received second injection 6 months after the first one. The patients were retrospectively evaluated after the 1st and the 2nd injections by means of standardized questionnaire forms and voiding diary records.

Results: In the 6-month follow-up, 10 patients (32.2%) were determined to have full response after the first injection. The number of patients with partial response and no response were found to be 15 (48.4%) and 6 (19.4%), respectively. The mean value of Dysfunctional Voiding and Incontinence Symptom Score (DVISS) of the patients with full response was 8.5 before the injection, which decreased to 1 at 6-month follow-up and to 0.5 at 12-month follow-up (p < 0.001). Twenty-one patients without full response after the first injection received a second injection 6 months after the first one. Full response was achieved in 9 (42.9%) of the 21 patients who had a second injection, but only partial response was achieved in 9 (42.9%). Three (14.3%) of the remaining patients did not respond to the second injection either. 1-year follow-up evaluations revealed that the rates of the full response, partial response, and no response were 61.3, 29, and 9.7%, respectively.

Conclusions: Based on our results, onaBoNTA therapy is an effective and reliable second-line off-label therapy in the management of patients with non-neurogenic OAB that is refractory to medical therapy. Asking the patients/guardians to fill out a standardized questionnaire form before and after the therapy enables easy and non-invasive assessment of the response to the therapy.

Keywords: Botulinum toxin A; Children; Overactive bladder; Urgency; Urinary incontinence.