Botulinum toxin injections in the management of non-neurogenic overactive bladders in children

The role of botulinum toxin in the management of nonneurogenic overactive bladder in children: Highlights for clinical practice. A systematic review

Overactive bladder (OAB) is the most common voiding dysfunction in children; however, nonneurogenic or idiopathic OAB remains poorly studied. First-line treatment includes conservative measures; however, as many patients are refractory, have adverse effects, or are contraindicated for anticholinergics, new options must be explored. This review covers the use of intravesical botulinum toxin (BoNT) for idiopathic OAB treatment in children, emphasizing its efficacy, safety, differences between toxins, doses, and injection techniques. Clinical results were promising, with all 8 studies reporting good results. All authors used BoNT type A (BoNT-A), either onabotulinum or abobotulinum toxin A. Response rates were variable, with full-response percentages of 32%-60%. As proven by the full-response rates of 50%, repeated injections are as safe and effective as first injections. Only a few cases of urinary tract infection, transient urinary retention, and hematuria have been reported, with no major local or systemic adverse effects. Despite these limitations, evidence encourages and supports BoNT-A use as a safe and effective treatment modality for refractory idiopathic OAB in pediatric settings, regardless of dosage and target toxin. To the best of our knowledge, this is the first systematic review of the use of intravesical BoNT-A for idiopathic OAB treatment in children.

Onabotulinum toxin-A versus extended release tolterodine in the management of idiopathic overactive bladder in children: A pilot randomised controlled trial (OVERT trial)

BACKGROUND

Idiopathic Overactive Bladder is the most common cause of urinary incontinence in children. Anticholinergic medications are successful in only 20% of those with daily wetting so there is a real need to find a more effective treatment for this condition. Onabotulinum toxin A injections are often used as a treatment but there have been no randomised controlled trials investigating effectiveness in children.

OBJECTIVE

To provide information that would inform the design and conduct of a definitive trial comparing onabotulinum toxin A with extended-release tolterodine for the management of therapy resistant idiopathic overactive bladder in children. Specific objectives were to assess rates of eligibility, recruitment, acceptability of randomisation, loss to follow-up, acceptability of urodynamic assessment and obtain primary outcome data for sample size estimation.

STUDY DESIGN

Single-centre, parallel, two-arm, open-label pilot randomised controlled trial. Eligible patients (aged 7-16 years) were recruited at Royal Manchester Children's Hospital and randomised (1:1) using a web-based system.

TRIAL REGISTRATION

EudraCT 2014-001068-36; Funding: UK NIHR Research for Patient Benefit Programme.

RESULTS

98 patients were assessed for eligibility, 85 (87%) were eligible for screening, parents of 62 (73%) provided consent, 46 (74%) remained eligible and were randomised (onabotulinum = 22, tolterodine = 24). All participants commenced allocated treatment. Two patients withdrew from follow-up. All participants underwent urodynamic assessment at baseline and 35 (76%) additionally at week 6. The mean (standard deviation) number of wetting episodes per day at week 6 was 1.4 (1.7) in the onabotulinum group and 1.6 (1.0) in the tolterodine group. There was one serious adverse event (probably related to the drug) and 22 non-serious adverse events reported by 8 participants in the onabotulinum group (36%). There were 23 non-serious adverse events reported by 9 participants in the tolterodine group (38%).

DISCUSSION

Recruitment was challenging but eligibility and consent rates were high as were retention rates. Treatment compliance in the botox group was high but it was difficult to measure in the tolterodine group. Treatment switching was also an issue.

CONCLUSIONS

Recruitment to a definitive trial was demonstrated to be feasible if a large number of centres are involved, though further consideration is required regarding trial design.

Evaluation of boys with daytime incontinence by combined cystourethroscopy, voiding cystourethrography and urodynamics

Objects: Approximately, 1% of school children have daytime urinary incontinence. The symptoms may be caused by an overactive bladder (OAB). In the evaluation of boys with OAB complaints, one should consider a possible urethral cause. The aim of the study was to evaluate the value of a diagnostic regime with cystourethroscopy, voiding cystourethrography (VCUG) and urodynamic pressure-flow studies in boys with OAB complaints after unsuccessful urotherapy and pharmacological therapy. Materials and Methods: Seventy-five boys (5-14 years old) were investigated with cystourethroscopy and within 24 h thereafter VCUG followed by urodynamic combined cystometry and pressure-flow study. All boys had daytime incontinence and urgency. Results: Sixty-one boys had no suspected urethral valves at cystoscopy or VCUG, and urodynamics showed no obstructed Pdet-Qmax. All 61 boys had detrusor overactivity. Two boys had late diagnosed urethral valves. In four boys, the initial cystourethroscopy was described as normal. The VCUG indicated presence of posterior urethral valves, but urodynamics showed no obstructed Pdet-Qmax. In eight boys, the initial cystourethroscopy was described as normal whereas urodynamics showed obstructed Pdet-Qmax. In four of these boys, VCUG showed abnormalities in the sphincter area but they were not described as suspected urethral valves. At repeat cystourethroscopy, urethral valves could still not be identified. Patient follow-up regarding achievement of continence after investigation guided treatment was in accordance with the literature. Conclusions: Boys can be safely evaluated by cystourethroscopy followed by urodynamics in search for a possible urethral problem. It is our suggestion, that VCUG can be restricted to those boys where urodynamics indicates obstruction or the findings by cystourethroscopy are uncertain.

Intradetrusor onabotulinum-a toxin injections in children with therapy-resistant idiopathic detrusor overactivity. A retrospective study

INTRODUCTION AND OBJECTIVE

The use of intravesical onabotulinum-A toxin (BoNT-A) injections in the treatment of idiopathic detrusor overactivity has been widely studied in adults [2-5]. However, in pediatric populations, study groups are small, and results are not yet sufficient to support this treatment as a standard practice. The aim of this study is to determine the effectiveness and safety of this treatment in children with non-neurogenic detrusor overactivity, resistant to conservative therapy.

MATERIAL AND METHODS

We retrospectively evaluated the effect and safety of the intradetrusor injection of 100 Units (U) of BoNT-A in 257 children with therapy-resistant non-neurogenic detrusor overactivity between May 2003 and August 2017. Outcome parameters were the number of daytime incontinence and enuresis episodes per week and bladder capacity (BC). Treatment outcomes were classified into complete response, partial response, or no response.

RESULTS

The database includes 257 children, of which are 102 girls and 155 boys. Median age of first BoNT-A injection was 8 years (range 4-18 years). Of the patients with enuresis, daytime incontinence or both, a complete response was seen in 50%, 45.7%, and 17%, respectively. BC was significantly higher after the first, second, and third injection of 100 U BoNT-A. We estimated that the mean duration of the effect of an injection with a dose of 100 U is around 12 months. After the first injection, one girl (0.4%) developed urinary retention, which required temporary clean intermittent catheterization (CIC). Seventeen patients (6.6%) developed a urinary tract infection. In three patients (1.2%), postoperative vesicoureteral reflux was seen.

DISCUSSION

A distinction between the effect on daytime incontinence and enuresis was made. A poorer effect on enuresis in children who suffered from both conditions was observed. Drawbacks of this study are its retrospective design and the lack of anticholinergic treatment standardization before and after BoNT-A injection.

CONCLUSION

BoNT-A injection is a potentially effective adjuvant therapy in the treatment of children with therapy-resistant overactive bladder (OAB). Bladder capacity increases significantly after the first, second, and third injections. A better effect on daytime incontinence than on enuresis was seen. Prospective randomized trials with standardization of conservative treatment and symptoms questionnaires are necessary to confirm the beneficial effect of BoNT-A injections on BC and incontinence.

WITHDRAWN: Optimization of the rat digit abduction score (DAS) assay: Evaluation of botulinum neurotoxin activity in the gastrocnemius lateralis, peronei, and extensor digitorum longus

The Publisher regrets that this article is an accidental duplication of an article that has already been published, https://doi.org/10.1016/j.toxcx.2020.100029. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

Current pharmacological management of idiopathic overactive bladder in children in the UK: a national survey of practice

BACKGROUND

Children with daytime urinary incontinence secondary to idiopathic overactive bladder (IOAB) commonly present to paediatric urologists following failure of standard urotherapy and/or 1st-line anticholinergics. Off-label oral medications and intravesical botulinum toxin A (BtA) are being increasingly used for treatment-refractory IOAB, despite the paucity of high-quality evidence and guidelines. Knowledge of contemporary paediatric urologists' practice allows specialists to keep up-to-date with current trends in the management of IOAB in children.

OBJECTIVES

1. To present an analysis of contemporary tertiary management of IOAB in children and 2. to highlight current trends in practice and identify areas of high variability in care for targeted research.

METHODS

Paediatric urologists (55 individuals) who attended the 2018 national British Association of Paediatric Urologists (BAPU) congress responded to a 20-question survey presented at the congress. Respondents could submit one answer per question, and one survey was taken per respondent, using secure software to disable any manipulation. Answers were analysed prospectively by a single reviewer.

RESULTS

Of UK paediatric urologists, 98% regularly manage children with IOAB, 48% use 48-h frequency/volume charts and others use three or seven-day bladder diaries to aid diagnosis. Oxybutynin is the 1st-line therapy for 85%, 2nd-line is tolterodine (53%), and 3rd-line is solifenacin (41%). Mirabegron is used either alone or in combination with solifenacin as 4th-line management by 55%. Those who use intravesical Botulinum toxin A (BtA) accounted for 81% and 84% of these perform invasive urodynamic assessment prior to BtA administration. Post-BtA, assessment was clinical in 18%, 24% use invasive urodynamics, whereas uroflowmetry is preferred by 58%. Of the paediatric urologists, 72% believe the most clinically significant outcome of treatment is patient-reported improvement. Treatment success is defined variably: 49% define success as completely dry, whereas 35% accept a 90% improvement as success.

CONCLUSIONS

Off-label medications are being used widely either alone or in combination by paediatric urologists. In oral therapy-resistant IOAB, BtA is being used by the majority of specialists, usually after formal urodynamic assessment. However, post-BtA assessment and evaluation of treatment success for IOAB are variable.

Pharmacologic therapies for the management of non-neurogenic urinary incontinence in children

Introduction: Non-neurogenic urinary incontinence in children is a common condition that affects the quality of life for both patients and parents. Symptoms may occur in the daytime, nighttime, or both and may be the result of structural and functional anomalies. Evaluation and management of associated co-morbidities, such as constipation is critical to management. Behavioral therapy is a fist line therapy in most cases of non-neurogenic urinary incontinence and pharmacologic therapy a second-line therapy.Areas covered: In this review, the authors cover the pharmacologic agents, FDA approved and commonly used non-FDA approved, available for the treatment of four non-structural etiologies of non-neurogenic urinary incontinence in children. These include nocturnal enuresis, overactive bladder, giggle incontinence, and dysfunctional voiding.Expert opinion: Non-neurogenic causes of urinary incontinence in children represent a complicated medical condition that requires both pharmacologic and non-pharmacologic management. Limited FDA-approved therapies as well as suboptimal results with approved therapies due to a lack in the understanding of the underlying pathophysiology and patient selection may lead to the use of alternative non-FDA approved therapies.

Intradetrusor injection of botulinum toxin A in children: a 10-year single centre experience

PURPOSE

We evaluated the efficacy and safety outcomes of endoscopic intradetrusor botulinum toxin A (BTA) injections for the treatment of children with neuropathic bladder (NB) and non-neuropathic bladder (NNB) with or without detrusor overactivity in a single centre with a retrospective analysis.

METHODS

For the period 2006-2015, children who received BTA in our hospital were analysed. They were divided into group 1, those with underlying NB and group 2, those without a clear neuropathic cause of symptoms (NNB). Data are given as percentages or medians (interquartile range).

RESULTS

Over the study period, 52 children (28 boys, 54%) received BTA, 28 in group 1 (54%; 17 (61%) boys) and 24 in group 2 (46%; 11 (46%) boys). Age at first injection was 11.8 (9.5-14.4) years. After initial injection, 40 (77%) reported symptomatic improvement, 17 (43%) becoming dry. There was no significant difference in response to initial injection between groups (p = 0.11). Duration of improvement after first injection was 7 (5.8-14) months. Twenty-five (48%) had further injections, of whom 3 (12%) were initial non-responders. Ongoing improvement was reported in 20 (80%), 11 (44%) of whom were dry. There was no significant difference in overall response to injections between groups (p = 0.11). Of the 11 non-responders, none (0/3) improved after subsequent injection and 3 (27%) subsequently underwent major urological surgery. Of the 40 who responded, 2 (5%) underwent major surgery.

CONCLUSION

BTA injection produced symptomatic improvement in 77% of our study population, with no significant differences in response between NB and NNB groups. In 95% of those who improved, major urinary tract procedures were avoided during the period studied. None of the initial non-responders improved after subsequent BTA injection. BTA injection is effective and reliable in the management of children with NB and NNB refractory to medical therapy.

Efficacy and safety of intradetrusor onabotulinumtoxinA injection for managing paediatric non-neurogenic overactive bladder: A prospective case-series study

Objectives: To evaluate the outcome of intradetrusor onabotulinumtoxinA (Botox®; Allergan Inc., Dublin, Ireland) (IDB) injection in children and adolescents with non-neurogenic overactive bladder (OAB) refractory or resistant to treatment.

Patients and Methods: In all, 91 patients underwent evaluation using subjective scores and urodynamic studies (UDS), including determination of maximum bladder capacity (MBC) and evaluating the capacity deficit vs the expected bladder capacity (EBC), and uroflowmetry determination of voided volume, maximum urinary flow rate (Q_max) and post-void residual urine volume (PVR). All patients received oxybutynin (0.3–0.5 mg/kg/day) for 3 months and re-evaluated patients who developed drug intolerability, persistence or recurrence of OAB received 100 U IDB injection using 20 injection sites, with trigone and sphincter sparing. All patients were re-evaluated 3-monthly for subjective scoring and at the end of the 12-month follow-up with UDS.

Results: In all, 43 patients underwent IDB injection and at the end of the 12-month follow-up the success rate for IDB injection was 90.7%. All patients showed progressively decreasing scores compared to baseline scores. At the 12-month follow-up, MBC, voided volume, and Q_max were significantly higher, whilst capacity deficit and PVR were significantly lower than baseline measures. The frequency of patients satisfied with the outcome of IDB was high.

Conclusion: For children with OAB refractory or resistant to biofeedback therapy, anti-cholinergic drugs must be tried first with IDB reserved for cases who fail to respond, are intolerant or recur after medical treatment. IDB using 100 U Botox, at 20 injection sites with trigone and sphincter sparing, is successful with a high satisfaction rate and free of postoperative problems.

Abbreviations: EBC: expected bladder capacity; IDB: intradetrusor onabotulinumtoxinA; MBC: maximum bladder capacity; OAB: overactive bladder; OABSS: Overactive Bladder Symptom Score; PPBC: Patient Perception of Bladder Condition; PVR: post-void residual urine volume; TENS: transcutaneous electrical nerve stimulation; Q_max: maximum urinary flow rate; UDS: urodynamic studies; UI: urinary incontinence

Onabotulinum toxin A in children with refractory idiopathic overactive bladder: medium-term outcomes

INTRODUCTION

Botulinum toxin-A (BtA) has been used for refractory idiopathic overactive bladder (IOAB) in children. Data on the optimum dose success rates, duration of effect, complications and medium-term outcomes are limited. This study aims to analyse the authors' experience to provide medium-term results of BtA in symptomatic refractory patients.

MATERIALS AND METHODS

Patients with refractory IOAB who were treated with BtA (Botox®) were retrospectively analysed. All patients had urodynamic study before treating with BtA. Group A had low-dose BtA (LDBtA) at 5 units/kg (maximum 150 units), and Group B had high-dose BtA (HDBtA) at 10 units/kg (maximum 300 Units). Post-BtA clinical response, functional bladder capacity (FBC) and postvoid residual (PVR) were assessed in addition to the duration of response.

RESULTS

Thirty-nine patients, 11 male and 28 female, were analysed. Forty-six percentage had symptom improvement (73% of males and 36% of females [P = 0.072, ns]). The difference in response rates between LDBtA and HDBtA was not statistically significant (P = 0.684). Increase in total bladder capacity (TBC) was greater in those given HDBtA (P ≤ 0.001), but the increase in FBC was not different between the groups, due to greater PVRs in the HDBtA group. Nine patients (23%) developed UTI; however, six of these patients suffered with UTI pre-BtA as well. Only three were asymptomatic after a single treatment with BtA. The remainder required further BtA or oral anticholinergic therapy. At a median follow-up of 35.4 months (interquartile range [IQR] 25.2-46.6), 12 (31%) were asymptomatic and off all therapy, 18 (46%) were still symptomatic despite therapy and 9 (23%) had their symptoms controlled on continuing treatment.

DISCUSSION AND CONCLUSIONS

Botulinum toxin-A improves symptoms in 46% of children after the first injection in refractory IOAB. Although HDBtA resulted in greater increase in bladder capacity, it conferred no advantage in terms of success rate or duration of response. Five units/kg may be an optimum dose to use as a first treatment with the understanding that some patients will require a higher dose. And, there will be a cohort of patients who need a dose lower than 5 units/kg. A higher dose is more likely to lead to PVR leading to urine stasis and UTIs. The success of BtA only lasts until its effect wears off, and the majority of this cohort (36/39) required continuing treatment with repeat BtA or anticholinergic agents. However, it remains a useful option in patients who are intolerant or unresponsive to anticholinergic medication with symptomatic resolution in 30% at medium-term follow-up.

Is there any Relationship Between Bladder Trabeculation and Efficacy and Safety of Intravesical Botulinum Toxin A Injection in Refractory Idiopathic Overactive Bladder Women?

Background:

Intradetrusor injection of botulinum toxin A (BTX-A) might serve as a minimally invasive substitute in patients with refractory idiopathic overactive bladder (RIOAB). The aim of this study was to evaluate the clinical outcomes related to two different doses of abo-BTX-A (AboBTX-A) in patients with RIOAB.

Materials and Methods:

This prospective clinical trial was performed on 55 women with RIOAB. After determination of trabeculation grade, 300 (no or mild) or 500 (moderate or severe) unit of AboBTX-A (Dysport) was intravesicaly injected. Before 1, 3, and 6 months after intervention, lower urinary tract symptoms during 24 h were recorded.

Results:

Of the study population, 62% had severe bladder trabeculation. The mean duration of overactive bladder (OAB) was 1.76 versus 5.85 years, for no or mild versus severe trabeculation, respectively. After injections of 300- and 500-unit dosage, there were 19% and 26% early complications such as urinary retention. There was a statistically significant difference between the two groups in OAB score after 1 month (P < 0.001) and duration of OAB symptoms, over three follow-up times (P < 0.001). The mean preinjection OAB scores between patients with and without recurrence were statistically significant (29.36 vs. 25.07; P < 0.03). Urinary tract infection as a late complication was distinguished in four patients.

Conclusion:

In RIOAB, by adjusted dosage of AboBTX-A related to the grade of bladder trabeculation, in addition to maintain efficacy, consequent complications might not be affected by dosage and the drug dosage could be increased to nearly 60% with less concern associated to complication

Adolescence transitional care in neurogenic detrusor overactivity and the use of OnabotulinumtoxinA: A clinical algorithm from an Italian consensus statement

AIMS

OnabotulinumtoxinA (onaBNTa) for treating neurogenic detrusor overactivity (NDO) is widely used after its regulatory approval in adults. Although the administration of onaBNTa is still considered off-label in children, data have already been reported on its efficacy and safety. Nowadays, there is a lack of standardized protocols for treatment of NDO with onaBNTa in adolescent patients in their transition from the childhood to the adult age. With the aim to address this issue a consensus panel was obtained.

METHODS

A panel of leading urologists and urogynaecologists skilled in functional urology, neuro-urology, urogynaecology, and pediatric urology participated in a consensus-forming project using a Delphi method to reach national consensus on NDO-onaBNTa treatment in adolescence transitional care.

RESULTS

In total, 11 experts participated. All panelists participated in the four phases of the consensus process. Consensus was reached if ≥70% of the experts agreed on recommendations. To facilitate a common understanding among all experts, a face-to-face consensus meeting was held in Rome in march 2015 and then with a follow-up teleconference in march 2017. By the end of the Delphi process, formal consensus was achieved for 100% of the items and an algorithm was then developed.

CONCLUSIONS

This manuscript represents the first report on the onaBNTa in adolescents. Young adults should be treated as a distinct sub-population in policy, planning, programming, and research, as strongly sustained by national public health care. This consensus and the algorithm could support multidisciplinary communication, reduce the extent of variations in clinical practice and optimize clinical decision making.