Use and Outcomes of Botulinum Toxin A for Both Neurogenic and Non-neurogenic Voiding Dysfunction in the Pediatric Patient

Purpose of ReviewIn this review, we seek to present the most recent data that is available and not perform an exhaustive review of the whole literature. Many recent publications have provided us with randomized prospective studies which confirmed much of the prior groundbreaking work done by the authors who published some of the original work in the field. In some cases, we may intersperse data from an adult study when there is a lack of data from a pediatric study.Recent FindingsIn a 48-week prospective, multicenter, randomized, double-blind study in children (aged 5-17 years) with neurogenic detrusor overactivity and urinary incontinence (UI) receiving onabotulinum toxin A, a reduction was noted in urinary incontinence along with an increase in first morning cathed urine volumes and increases in maximum cystometric volumes as well as a decrease in pressure. Safety was similar across doses; urinary tract infection was the most frequent adverse event experienced (24). In a systematic review published in 2021 (25) looking at 16 studies that included a total of 455 patients with neurogenic bladder, 15 of 16 reported improvement in incontinence, vesicoureteral reflux (VUR), UTI, bowel dysfunction, hydronephrosis, and patient-reported satisfaction. Thirteen studies reported an improvement in incontinence, with a post-injection improvement rate of 54-100%. Six studies reported improvements in the rate of VUR (73-100%).In patients with non-neurogenic bladder overactivity involving 257 children, a complete response was seen in patients with enuresis, daytime incontinence, or both, in 50%, 45.7%, and 17%, respectively. Bladder capacity was significantly increased after the first, second, and third injection of 100 U OnaBTX-A. Other studies have shown similar results as well in non-neurogenic OAB.Recent FindingsIn a 48-week prospective, multicenter, randomized, double-blind study in children (aged 5-17 years) with neurogenic detrusor overactivity and urinary incontinence (UI) receiving onabotulinum toxin A, a reduction was noted in urinary incontinence along with an increase in first morning cathed urine volumes and increases in maximum cystometric volumes as well as a decrease in pressure. Safety was similar across doses; urinary tract infection was the most frequent adverse event experienced (24). In a systematic review published in 2021 (25) looking at 16 studies that included a total of 455 patients with neurogenic bladder, 15 of 16 reported improvement in incontinence, vesicoureteral reflux (VUR), UTI, bowel dysfunction, hydronephrosis, and patient-reported satisfaction. Thirteen studies reported an improvement in incontinence, with a post-injection improvement rate of 54-100%. Six studies reported improvements in the rate of VUR (73-100%).In patients with non-neurogenic bladder overactivity involving 257 children, a complete response was seen in patients with enuresis, daytime incontinence, or both, in 50%, 45.7%, and 17%, respectively. Bladder capacity was significantly increased after the first, second, and third injection of 100 U OnaBTX-A. Other studies have shown similar results as well in non-neurogenic OAB.SummaryThe most recent data appears to be convincing that Botulinum toxin A is a valuable tool in the treatment of neurogenic and non-neurogenic detrusor overactivity as well as sphincteric dysfunction. There are differences in the length of time the botulinum toxin A efficacy persists after injection in the bladder between neurogenic and non-neurogenic patients. With the non-neurogenic patients experiencing a longer symptomatic benefit than the neurogenic patients. BTX-A is not a cure-all and may help stave off augmentation cystoplasty in some patients, but it may not be able to do so in severely compromised bladders especially those treated in a non-proactive fashion. Neutralizing antibody formation is not a major issue in the vast majority of patients and the formation of antibodies does not necessarily equate with loss of function.