Botulinum Toxin Injection for Medically Refractory Neurogenic Bladder in Children: A Systematic Review

Botulinum Neurotoxin Type A in paediatric non-neurogenic therapy resistant overactive bladder: a cohort study

INTRODUCTION AND OBJECTIVE

Intradetrusor Botulinum Neurotoxin Type A (BoNT-A) is an increasingly applied treatment modality for overactive bladder (OAB) in children with refractory urinary incontinence. Despite that, evidence is sparse, and the potential not fully understood. The aim of this study was to evaluate the effectiveness and safety of intradetrusor injection in children with refractory functional OAB and urinary incontinence. Furthermore, we aimed to identify predictors of efficacy and side effects to BoNT-A treatment.

MATERIALS AND METHODS

We conducted a cohort study of children with OAB and urinary incontinence who received intradetrusor injection of BoNT-A in the period 01.01.2016 to 31.12.2020 at our centre. All patients were refractory to standard urotherapy, anticholinergics, mirabegron and the combination of these treatments. Patients with neurogenic bladder were excluded. Primary endpoint was the reduction on the frequency of urinary incontinence episodes from baseline. Secondary endpoints included urodynamic parameters and uroflowmetry characteristics as well as side effects.

RESULTS

Forty-three children (mean age at first treatment 10.7 ± 1.8, 30 males) were included. After first treatment, a reduction of ≥ 50% in incontinence episodes was seen in 58% of patients with daytime urinary incontinence (DUI) and 47% of patients with nocturnal enuresis (NE). Adverse events, mainly urinary tract infections (UTI), were reported by 16% of patients after first treatment. Our analysis identified normal cystometric compliance as a significant predictor of treatment effect We estimated the mean duration of effect to be approximately 7 months.

CONCLUSIONS

Intradetrusor BoNT-A injection appears to be a safe and effective option in treating refractory urinary incontinent children with overactive bladder. We identified cystometric compliance as a predictor of response. Most children necessitate repeated treatments. Further prospective and controlled studies are necessary in order to fully identify predictors and potential of treatment.

Intravesical Botulin Toxin-A Injections for Neurogenic Bladder Dysfunction in Children: Summary Update on Last 10 Years of Research

Neurogenic bladder dysfunction (NB) represents a challenge in pediatric urology. Intravesical botulin toxin-A (BTX-A) bladder injection is part of the armamentarium for the treatment of this condition, usually after failed first-line medical strategies and before the escalation to more invasive options such as neuromodulation or augmented cystoplasty in severe cases. However, there is still a lack of consensus about the appropriate treatment modality for the pediatric population. A review of the last 10 years' research was performed on the PubMed database by two authors. Articles doubly selected and meeting the inclusion criteria were collected and analyzed for their study type, demographics, neurological disease(s) at diagnosis, BTX-A treatment modality and duration, previous treatment, clinical and urodynamic parameters, adverse events, outcomes, and follow-ups. A total of 285 studies were initially selected, 16 of which matched the inclusion criteria. A cohort of 630 patients was treated with BTX-A at a median age of 9.7 years, 40% of which had a diagnosis of myelomeningocele. The results of the selected publications show the overall efficacy and safety of BTX-A injections in children and confirmed BTX-A as a valuable strategy for NB treatment in pediatric population. Nevertheless, up to now, the literature on this topic offers scarce uniformity among the published series and poor protocol standardization.

Understanding Clinical Effectiveness and Safety Implications of Botulinum Toxin in Children: A Narrative Review of the Literature

Since its first approval by the Food and Drug Administration in 1989 for strabismus, botulinum toxin indications of use have been widely expanded. Due to its anticholinergic properties, this toxin is currently approved in adult patients for the treatment of a wide range of neuromuscular, otolaryngologic, orthopedic, gastrointestinal, and urologic disorders. Approved pediatric indications of use include the treatment of blepharospasm associated with dystonia, strabismus, lower-limb spasticity, focal spasticity in patients with cerebral palsy, and neurogenic detrusor overactivity. Alongside these approved indications, botulinum toxin is extensively used off-label. Although several clinical studies have shown that botulinum toxin is effective and well-tolerated in children, uncertainties persist regarding its long-term effects on growth and appropriate dosing in this population. As such, further research is needed to better define the botulinum toxin risk-benefit profile and expand approved uses in pediatrics. This narrative review aimed to provide a broad overview of the evidence concerning the clinical effectiveness and safety of BoNT with respect to its principal authorized and non-authorized pediatric therapeutic indications, as well as to describe perspectives on its future use in children.

Long-Term Adherence to Onabotulinum Toxin-A Intradetrusor Injections for Neurogenic Dysfunction in Children-A Retrospective Single-Center Evaluation

Onabotulinum Toxin-A (BTX-A) is a second-line treatment for neurogenic bladder (NB). It requires repeated injections over time, which is a possible limit for long-term adherence, especially in children, as general anesthesia is required. Almost 50% of adults discontinue therapy; few data on pediatric patients are present. The aim of this study is to share our long-term experience of BTX-A adherence in children. This study is a retrospective review of 230 refractory NB patients treated with BTX-A. The inclusion criteria were ≥3 treatments and the first injection performed ≥10 years before the study endpoint. Fifty-four patients were included. Mean follow-up was 10.2 years; mean treatment number was 6.4 for each patient. During follow-up, 7% did not need BTX-A anymore; 76% discontinued therapy, with a prevalence of acquired NB (64% acquired vs. 34% congenital; p = 0.03); sex-based and urodynamic findings did not influence the discontinuation rate (p = 0.6, p = 0.2, respectively). Considering those who withdrew from the therapy, 43% were lost to follow-up/died after a mean of 7.5 years (although 33% still experienced clinical efficacy); 33% changed therapy after a mean of 5.8 years (with reduced efficacy in 22%, persistent efficacy in 11%). BTX-A is a safe and effective therapy for pediatric patients. The treatment abandonment rate is higher for children than for adults; no specific reasons were highlighted. It is necessary to evaluate any age-specific factors to explain these data.

Multidisciplinary management of people with spina bifida across the lifespan

The average worldwide prevalence of neural tube defects (NTDs) is 1.0 per 1000 births. Its development is multifactorial due to genetic and non-genetic factors. Spina bifida (SB) is one of main representatives of NTD. The spinal cord lesion level is the main determinant of the level of paralysis, numbness, and difficulties with bladder/bowel functions. Myelomeningocele prenatal repair reduces hydrocephalus and hindbrain herniation and improves motor function. The severity of hydrocephalus is associated with poorer neurodevelopmental outcomes whether operated on prenatally or after birth. People with SB tend to have a lower IQ and cognitive difficulties. Early diagnosis, proactivity, and lifelong multidisciplinary follow-up are key protective issues. Invasive urological interventions should be considered in selected patients after failure of conservative treatment. Transition to adult care should be well planned as it is challenging. Health literacy is directly associated with success at transition. Sexuality and fertility should be addressed before/during puberty. Overall, the rates of fecal and urinary continence and skin breakdown increase with age, whereas the ability to ambulate declines with age. Bowel and urinary incontinence are independent predictors of lower health-related quality of life (HRQoL) in adults with SB. Bowel incontinence has negative impact on HRQoL regardless of frequency or amount. Long-term caregiver support should be offered at diagnosis. Survival at a mean of 50 years is poor, at 32%, due to central nervous system deaths, cancer, urological disease, and sepsis. Challenges to implementation of recommended practices exist, especially in low and middle-income countries.

Long-term complications and outcomes of augmentation cystoplasty in children with neurogenic bladder

Augmentation cystoplasty (AC) is an effective surgical procedure for patients with neurogenic bladder whenever conservative treatments have failed. The present study aimed to determine the risks of metabolic complications, malignancy, long-term outcomes and histopathologic changes of native bladder and the augmented intestine after AC in children with neurogenic bladder. Pediatric patients < 18 years who underwent AC between 2000 and 2020 were enrolled. Early postoperative complications, long-term outcomes and histopathologic changes in mucosal biopsies of native bladder and the augmented intestine after AC were reviewed. Twenty-two patients with a mean age of 7.6 ± 4.4 years were included. The ileum was used in 19 patients and the sigmoid colon in 3 patients. The length of hospital stay was 14.8 ± 6.8 days. Post-operatively, the urinary continence rate improved from 22.7 to 81.8% (p < 0.001). Hydronephrosis resolved in 17 of 19 patients. Vesicoureteral reflux resolved in 16 (64.0%) of the refluxing ureter units and was downgraded in 7 (28.0%). Grades of hydronephrosis and reflux significantly improved following AC (p < 0.001). The estimated glomerular filtration rate also significantly increased (p = 0.012). Formation of urinary tract stones was the most frequent late complication (in 8 patients, 36.4%). Life-threatening spontaneous bladder perforation occurred in 1 patient. After a mean follow-up of 13.4 ± 5.9 years, there were no cases of mortality, new-onset symptomatic metabolic acidosis, or changes in serum electrolytes. Of the 17 patients who were followed for > 10 years, no cases of malignancy or metaplastic changes were identified in the native bladder or augmented bowel epithelium. AC is a safe and effective procedure with low surgical and metabolic complication rates. In addition, AC provides a satisfactory continence rate and long-term protection of renal function, increases functional capacity, and regresses reflux and hydronephrosis. Individualized surveillance is recommended for the early identification of urolithiasis and metabolic disturbances.

Onabotulinum Toxin A Intradetrusor Injections in Children with Neurogenic Lower Urinary Tract Dysfunction: Long-Term Histological Effects on the Bladder Wall

BACKGROUND

In the last twenty-five years, Onabotulinum Toxin A (BTX-A) has gained increasing popularity for neurogenic lower urinary tract dysfunction (NLUTD) treatment. To maintain its efficacy, repeated BTX-A intradetrusor injections are required over time, with unknown effects on the bladder wall in children. The aim of this paper is to report long-term effects on the bladder wall in children treated with BTX-A.

METHODS

Children with NLUTD not responsive to anticholinergics were treated with BTX-A, according to our protocol, with bladder wall control using endoscopic cold-cup biopsy. Specimens were evaluated considering edema, chronic inflammation, and fibrosis.

RESULTS

Of the 230 patients treated from 1997 to 2022, we considered only specimens obtained in patients who had received ≥5 treatments (36 children), considered as the threshold to evaluate clinical effectiveness on long-term treatment with BTX-A. Most of them had congenital NLUTD (25 patients) and detrusor overactivity (27 patients). In all, increased edema and chronic inflammation with reduced fibrosis over time was reported; these data were not statistically significant. No difference was observed between patients with congenital and acquired diseases.

CONCLUSIONS

Repeated intradetrusor BTX-A injections are not related to significant histological alterations in children, similarly with adults, and repeated injections could be considered safe.

Efficacy of Intravesical Botulinum Toxin A Injection in the Treatment of Refractory Overactive Bladder in Children

This study aimed to evaluate the efficacy of intravesical botulinum toxin A (BoNT-A) injections for the treatment of pediatric overactive bladder (OAB) by exploring the differential treatment outcomes in children with different OAB etiologies and those who received additional intrasphincteric BoNT-A injections. We performed a retrospective review of all pediatric patients who received intravesical BoNT-A injections between January 2002 and December 2021. All patients underwent a urodynamic study at baseline and three months after BoNT-A administration. A Global Response Assessment (GRA) score of ≥2 at three months after BoNT-A injection was defined as successful treatment. Fifteen pediatric patients (median age, 11 years), including six boys and nine girls, were enrolled in the study. A statistically significant decrease in detrusor pressure from baseline to three months postoperatively was observed. Thirteen (86.7%) patients reported successful results (GRA ≥ 2). The cause of OAB and additional intrasphincteric BoNT-A injections did not affect the improvement in urodynamic parameters and treatment success. The study demonstrated that intravesical BoNT-A injection is effective and safe for the treatment of neurogenic and non-neurogenic OAB in children refractory to conventional therapies. Additionally, intrasphincteric BoNT-A injections do not provide additional benefits in the treatment of pediatric OAB.

Effectiveness and safety of sacral neuromodulation for neurogenic bladder

BACKGROUND

The treatment of neurogenic bladder (NB) is a challenge because conventional therapy often fails. Sacral neuromodulation (SNM) is a minimally invasive technique and an unconventional treatment for neurogenic bladder. Its research is still in the exploratory stage. The research on its effectiveness and safety is not clear.

OBJECTIVE

To assess the effectiveness and safety of sacral neuromodulation (SNM) for neurogenic bladder (NB).

METHODS

By searching the PubMed databases and Cochrane Library databases, combined with the method of literature tracing, the clinical researches and works on neurogenic bladder and sacral neuromodulation therapy were collected. Two reviewers independently selected and extracted data, (1) determine whether the study meets the inclusion criteria and exclude the literature that meets the exclusion criteria. (2) Researchers' screening results and data, if there are differences in the results, will be discussed to eliminate the differences. (3) Read the full text of the literature carefully to determine the final literature to be included. (4) The relevant data of 11 independent studies, a total of 291 patients, were systematically reviewed using review manager 5.3 software.

RESULTS

This research included 11 independent studies with a total of 291 patients. The improvements of main outcomes before and after SNM therapy were significant: incontinence episodes /24 h (WMD -2.52; 95%CI-3.14-1.90; p <0.001), frequency/24 h (WMD-5.96; 95%CI -6.27，-5.66; p <0.001), voiding volume (WMD 116.09 mL; 95%CI 86.68，145.51; p <0.001), cystometric capacity (WMD 129.84 mL; 95%CI 100.53, 159.15; p <0.001), post-void residual volume (WMD-198.00 mL; 95%CI-264.60, -131.40; p <0.001), clean intermittent self-catheterization/24 h (WMD-2.48; 95%CI -2.96, -2.00; p <0.001).

CONCLUSION

This systematic review indicated that the sacral neuromodulation treatment for neurogenic bladder was effective and safe.