Efficacy and Safety of Local Steroids for Urethra Strictures: A Systematic Review and Meta-Analysis

Pharmacotherapy of urethral stricture

Urethral stricture is characterized by the chronic formation of fibrous tissue, leading to the narrowing of the urethral lumen. Despite the availability of various endoscopic treatments, the recurrence of urethral strictures remains a common challenge. Postsurgery pharmacotherapy targeting tissue fibrosis is a promising option for reducing recurrence rates. Although drugs cannot replace surgery, they can be used as adjuvant therapies to improve outcomes. In this regard, many drugs have been proposed based on the mechanisms underlying the pathophysiology of urethral stricture. Ongoing studies have obtained substantial progress in treating urethral strictures, highlighting the potential for improved drug effectiveness through appropriate clinical delivery methods. Therefore, this review summarizes the latest researches on the mechanisms related to the pathophysiology of urethral stricture and the drugs to provide a theoretical basis and new insights for the effective use and future advancements in drug therapy for urethral stricture.

[Evaluation and management of urethral strictures-guideline summary 2024 : part 1-anterior urethra]

In recent years, several international urological societies have published guidelines on the diagnosis, treatment, and follow-up of urethral strictures, but a guideline for the German-speaking region has not been available to date. This summary provides a detailed comparison of the guidelines of the European Association of Urology (EAU), American Urological Association (AUA) and the Société Internationale d'Urologie (SIU) with regard to the treatment of anterior urethral strictures, i.e. from the bulbar urethra to the meatus. In the following work, differences and specific recommendations in the guidelines are highlighted. In particular, the three guidelines largely agree with regard to diagnostic workup and follow-up. However, divergences exist in the management of anterior urethral strictures, particularly with regard to the use of endoscopic therapeutic approaches and the use of urethral stents. In addition, the EAU provides more comprehensive and detailed recommendations on urethroplasty techniques and specific patient follow-up. The EAU guidelines are the most current and were the first to include instructions for urethral strictures in women and individuals with gender incongruence after genital approximation surgery. Reconstructive urology is a rapidly evolving specialty and, thus, the clinical approach has been changing accordingly. Although guideline recommendations have become more inclusive and comprehensive, more high-quality data are needed to further improve the level of evidence.

Safety of Xiaflex® (Collagenase Clostridium histolyticum) Treatment for Adult Anterior Urethral Stricture Disease

Male urethral stricture disease is highly prevalent and difficult to treat due to potential complications. Minimally invasive treatments tend to have high recurrence rates, keeping urethroplasty as the gold standard. Collagenase Clostridium histolyticum (CCH) has been used in humans to treat fibrosis in a minimally invasive manner. Herein, we present the preliminary results from treatments of three males with urethral stricture as a feasibility and safety evaluation of the first-in-human CCH treatment for male urethral stricture disease.

Is a Course of Intermittent Self-dilatation with Topical Corticosteroids Superior at Stabilising Urethral Stricture Disease in Men and Improving Functional Outcomes over a Course of Intermittent Self-dilatation Alone? A Systematic Review and Meta-analysis

Context

Intermittent self-dilatation (ISD) is a therapeutic strategy used to stabilise a urethral stricture and postpone or avoid further treatment. Adding corticosteroids to this mode of management might further enhance its outcomes by downregulation of collagen deposition and excessive scar tissue formation.

Objective

To explore whether a course of ISD with topical corticosteroids is superior at stabilising urethral stricture disease in men and improving functional outcomes over a course of ISD alone.

Evidence acquisition

This systematic review and meta-analysis was undertaken by the European Association of Urology Urethral Strictures Guideline Panel according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines (CRD42021256744). The primary benefit outcome was successful stabilisation of the urethral stricture. Treatment-related complications were the primary harm outcome.

Evidence synthesis

In total, 978 records were screened for eligibility, ultimately leading to five included studies, all randomised controlled trials, comprising 250 patients, of whom 124 underwent a course of ISD with corticosteroids and 126 underwent a course of ISD alone, all after direct vision internal urethrotomy (DVIU). Successful stabilisation of the stricture was achieved in 77% and 64% of patients in the group with and without corticosteroids, respectively (p = 0.04). No extra complications related to the addition of corticosteroids to the ISD regimen were reported. The risk of bias of the included studies was generally unclear to high.

Conclusions

Based on the currently available data, a course of ISD with topical corticosteroids appears to be safe and superior at stabilising a urethral stricture after DVIU in the short term to a course of ISD alone. However, given the unclear to high risk of bias in the included studies, further high-quality studies are needed to fully underpin this.

Patient summary

This study shows that addition of topical corticosteroids to intermittent self-dilatation after direct vision internal urethrotomy can better stabilise the stricture in the short term.

Effect of Nintedanib on healing and fibrosis in rats with experimentally induced urethral injury

AIM

We aimed to determine the effectiveness of Nintedanib treatment, which has known antifibrotic effect, in preventing fibrosis after urethral trauma.

MATERIAL AND METHODS

Twenty-three adult Sprague-Dawley rats were divided randomly into 3 different groups: Sham, Urethral injury group (UI) and Urethral injury+ Nintedanib (UI+N). The urethral injury model was made with a pediatric urethrotome knife. Nintedanib was administered at a dose of 50mg/kg by oral gavage for 14 days at the same time every day. After 14 days of treatment, all rats were performed penectomy under general anesthesia. Urethral tissue was evaluated histopathologically (congestion, inflammatory cell infiltration and spongiofibrosis) and immunohistochemically (transforming growth factor (TBF) Beta-1 and vascular endothelial growth factor receptor 2 (VEBFR2)).

RESULTS

Histopathological findings: Group UI had higher scores in all categories (congestion, inflammatory cell infiltration, and spongiofibrosis), followed by Group UI+N and Group Sham, respectively. A statistically significant difference was found between Group UI and Group UI+N in terms of the scores of histopathological parameters (p<0.05). Immunohistochemical findings: Group UI had higher scores in both categories, followed by Group UI+N and Group Sham, respectively. A statistically significant difference was found between Group UI and Group UI+N in TGF Beta-1 and VEGF scores (p<0.05).

CONCLUSION

We found that Nintedanib administration after urethral trauma reduced inflammation and fibrosis histologically and immunohistochemically. The positive effect of Nintedanib on inflammation and fibrosis after urethral trauma reported in this animal study is encouraging for a potential clinical human application.

Effect of local steroids on urethral strictures: A systematic review and meta-analysis

PURPOSE

Urethral stricture disease is common and has high associated morbidity and impact on quality-of-life. This systematic review and meta-analysis aims to summarise current evidence on the efficacy of local urethral steroids post-direct vision internal urethrotomy (DVIU) for the treatment of urethral strictures in males.

MATERIALS AND METHODS

A comprehensive search was performed using reputable databases and registries, up to 22 February 2022. Only randomised control trials in which participants were randomised to DVIU plus local urethral steroids versus DVIU only were included. Statistical analyses were performed using a random-effects model. Quality of evidence was rated according to the GRADE approach.

RESULTS

The search identified seven studies in which 365 participants were randomised to DVIU plus local urethral steroids versus DVIU only. The application of local steroids appeared to reduce recurrence rates (risk ratio, 0.67; 95% confidence interval [CI], 0.49-0.90) and time-to-recurrence (hazard ratio, 0.58; 95% CI, 0.39-0.85). Qmax also improved following steroid application (mean difference, 0.82; 95% CI, -1.02-2.66); however, this was not statistically significant. No heterogeneity was identified between included studies for all outcomes. The certainty of evidence was downgraded due to study limitations with a small sample size and unclear risk-of-bias related to insufficient trial information.

CONCLUSIONS

Compared to DVIU alone, adjuvant steroids applied to the urethra may reduce risk of recurrence and time-to-recurrence. These findings were statistically significant and likely also clinically significant given low associated costs and risk. However, more robust randomised trials are necessary to enhance the validity of these outcomes.

Comparative review of the guidelines for anterior urethral stricture

PURPOSE

We aimed to provide a detailed comparison between the American Urologic Association (AUA), Société Internationale d'Urologie (SIU), and the European Association of Urology (EAU) guidelines on the evaluation, management, and follow-up of the patients with anterior urethral stricture disease (USD).

METHODS

The urethral stricture guidelines from SUI, AUA, and EAU were collected and evaluated regarding the recommendations on diagnosis, evaluation, and treatment of anterior USD. The strength of evidence for each statement was included and discussed when guidelines differed.

RESULTS

While the guidelines remarkably align in terms of the diagnostic workup and follow-up, there is discordance in the management of anterior urethral strictures, specifically for the use of endoscopic treatment and stenting. Further, the EAU offers more comprehensive recommendations regarding urethroplasty techniques and patient follow-up. The EAU guidelines are the most recent and first to offer guidance for USD in transgender people and women.

CONCLUSION

Reconstructive urology is a rapidly adapting field, and best practices change accordingly. Guideline statements have become more inclusive and expansive but will require further research to improve the level of evidence and continue to provide patients and providers with the best treatment plans.

Ability of photocurable gelatin to prevent stricture recurrence after urethral dilation in rabbits

OBJECTIVES

To evaluate the ability of photocurable gelatin to prevent stricture recurrence after urethral dilation in a rabbit urethral stricture model.

METHODS

We created urethral strictures in the bulbar urethras of 10 male Japanese white rabbits using electrocoagulation. After 1 month, the rabbits were randomly divided into Group A (n = 5; urethral stricture dilation and the local application of photocurable gelatin using a ruthenium photoinitiator and irradiation with a light-emitting diode light [λ = 455 nm, 50 mW/cm2 ] for 1 min) and Group B (n = 5; dilation only). Urethral stricture status was evaluated 1-2 months later by retrograde urethrography and urethroscopy. The lumen ratio (urethral width at the stricture site to the normal urethral width on retrograde urethrography) was calculated. Urethral patency was considered to be improved when the urethral lumen could accommodate a 10-Fr urethroscope without resistance. Urethral specimens were harvested for histopathological examination.

RESULTS

The mean lumen ratio did not differ significantly between Groups A and B before dilation (25.8% vs 23.4%; P = 0.40), but differed significantly after dilation (65.5% vs 27.3%, respectively; P = 0.03). Urethral patency improved in all rabbits in Group A (100%) versus one rabbit in Group B (20%; P = 0.02). The mean circumference of the regenerated urethral epithelium at the stricture site was larger in Group A than in Group B (14 mm vs 6.6 mm; P = 0.06).

CONCLUSIONS

Photocurable gelatin can reduce urethral stricture recurrence after dilation in a rabbit model.

The use of local therapy in preventing urethral strictures: A systematic review

Background

Urethral stricture disease is a common problem amongst men in Western countries often leading to a decreased quality of life. Current endoscopic treatment procedure shows an unsatisfying stricture recurrence rate which could be improved by addition of local therapies.

Objectives

To provide an overview of both preclinical and clinical studies in order to investigate current level of evidence on the addition of local therapy to improve urethral stricture recurrence rates after endoscopic procedures.

Methods

We performed a literature search in December 2020 and August 2021 using Cochrane, Embase, PubMed, Scopus and Web of Science and identified articles through combinations of search terms for ‘urethral stricture disease’, ‘stricture formation’ and ‘local interventions’. We used the SYRCLE, RoB-2 and ROBINS-I tools to assess risk of bias across included studies. We did not perform a meta-analysis due to methodological differences between studies.

Results

We included 32 articles in the qualitative analysis, 20 of which were preclinical studies and 12 clinical studies. Regarding preclinical articles using an animal model, nearly all interventions showed to have a positive effect on either urethral fibrosis, urethral stricture formation and/or fibrotic protein expression levels. Here, immunosuppressants and chemotherapeutics seemed most promising for possible clinical purposes. Regarding clinical studies, mitomycin-C and hyaluronic acid and carboxymethylcellulose showed positive effects on urethral stricture recurrence rates with low to intermediate risk of bias across studies. However, the positive clinical effects of mitomycin-C and steroids seemed to decrease in studies with a longer follow-up time.

Conclusion

Although local adjuvant use of mitomycin-C or hyaluronic acid and carboxymethylcellulose may carry clinical potential to improve urethral structure recurrence rates after endoscopic procedures, we believe that a large, well-designed RCT with a yearlong follow-up time is necessary to identify the true clinical value.

A Systematic Review and Meta-analysis of Adjuncts to Minimally Invasive Treatment of Urethral Stricture in Men

CONTEXT

Urethral stricture disease (USD) is initially managed with minimally invasive techniques such as urethrotomy and urethral dilatation. Minimally invasive techniques are associated with a high recurrence rate, especially in recurrent USD. Adjunctive measures, such as local drug injection, have been used in an attempt to reduce recurrence rates.

OBJECTIVE

To systematically review evidence for the efficacy and safety of adjuncts used alongside minimally invasive treatment of USD.

EVIDENCE ACQUISITION

A systematic review of the literature published between 1990 and 2020 was conducted in accordance with the PRISMA checklist.

EVIDENCE SYNTHESIS

A total of 26 studies were included in the systematic review, from which 13 different adjuncts were identified, including intralesional injection (triamcinolone, n = 135; prednisolone, n = 58; mitomycin C, n = 142; steroid-mitomycin C-hyaluronidase, n = 103, triamcinolone-mitomycin C-N-acetyl cysteine, n = 50; platelet-rich plasma, n = 44), intraluminal instillation (mitomycin C, n = 20; hyaluronic acid and carboxymethylcellulose, n = 70; captopril, n = 37; 192-iridium brachytherapy, n = 10), application via a lubricated catheter (triamcinolone, n = 124), application via a coated balloon (paclitaxel, n = 106), and enteral application (tamoxifen, n = 30; deflazacort, n = 36). Overall, 13 randomised controlled trials were included in the meta-analysis. Use of any adjunct was associated with a lower rate of USD recurrence (odds ratio [OR] 0.37, 95% confidence interval [CI] 0.27-0.50; p <  0.001) compared to no adjunct use. Of all the adjuncts, mitomycin C was associated with the lowest rate of USD recurrence (intralesional injection: OR 0.23, 95% CI 0.11-0.48; p <  0.001; intraluminal injection: OR 0.11, 95% CI 0.02-0.61; p =  0.01). Urinary tract infection (2.9-14%), bleeding (8.8%), and extravasation (5.8%) were associated with steroid injection; pruritis of the urethra (61%) occurred after instillation of captopril; mild gynaecomastia (6.7%) and gastrointestinal side effects (6.7%) were associated with oral tamoxifen.

CONCLUSIONS

Adjuncts to minimally invasive treatment of USD appear to lower the recurrence rate and are associated with a low adjunct-specific complication rate. However, the studies included were at high risk of bias. Mitomycin C is the adjunct supported by the highest level of evidence.

PATIENT SUMMARY

We reviewed studies on additional therapies (called adjuncts) to minimally invasive treatments for narrowing of the urethra in men. Adjuncts such as mitomycin C injection result in a lower recurrence rate compared to no adjunct use. The use of adjuncts appeared to be safe and complications are uncommon; however, the studies were small and of low quality.

European Association of Urology Guidelines on Urethral Stricture Disease (Part 1): Management of Male Urethral Stricture Disease

OBJECTIVE

To present a summary of the 2021 version of the European Association of Urology (EAU) guidelines on management of male urethral stricture disease.

EVIDENCE ACQUISITION

The panel performed a literature review on these topics covering a time frame between 2008 and 2018, and used predefined inclusion and exclusion criteria for the literature to be selected. Key papers beyond this time period could be included as per panel consensus. A strength rating for each recommendation was added based on a review of the available literature and after panel discussion.

EVIDENCE SYNTHESIS

Management of male urethral strictures has extensively been described in literature. Nevertheless, few well-designed studies providing high level of evidence are available. In well-resourced countries, iatrogenic injury to the urethra is one of the most common causes of strictures. Asymptomatic strictures do not always need active treatment. Endoluminal treatments can be used for short, nonobliterative strictures at the bulbar and posterior urethra as first-line treatment. Repetitive endoluminal treatments are not curative. Urethroplasty encompasses a multitude of techniques, and adaptation of the technique to the local conditions of the stricture is crucial to obtain durable patency rates.

CONCLUSIONS

Management of male urethral strictures is complex, and a multitude of techniques are available. Selection of the appropriate technique is crucial, and these guidelines provide relevant recommendations.

PATIENT SUMMARY

Injury to the urethra by medical interventions is one of the most common reasons of male urethral stricture disease in well-resourced countries. Although different techniques are available to manage urethral strictures, not every technique is appropriate for every type of stricture. These guidelines, developed based on an extensive literature review, aim to guide physicians in the selection of the appropriate technique(s) to treat a specific type of urethral stricture.

The standard for the management of male urethral strictures in the UK: a consensus document

Objective:

The aim of this study was to establish an evidence-based best clinical practice consensus for the management of urethral stricture disease in the UK.

Methods:

A systematic review of optimal management of urethral stricture generated a base document which was endorsed by the British Association of Urological Surgeons (BAUS) section of Andrology and Genito-Urinary Reconstructive Surgeons (AGUS). A two-round electronic mail modified Delphi survey of 43 consultant reconstructive urologists, members of the British Association of Genito-Urinary Reconstructive Surgeons (BAGURS), was then performed. The panel’s views about the base document was sought in seven domains: definition, diagnosis, investigation, conservative, endoscopic and reconstructive treatments, and follow up. Responses were collated and used to modify the base to achieve a consensus statement.

Results:

In round one of the Delphi process four panel members commented on the base document and seven in round two. Consensus was thereby reached on 38 statements regarding definition (one), diagnosis (three), investigation (two), conservative/endoscopic (five) and reconstructive (24) treatments and follow up (three) for the management of urethral stricture disease.

Conclusion:

This consensus statement will help standardise care, provide guidance on the management of urethral stricture disease, and assist in clinical decision-making for healthcare professionals of all grades.

A drug-coated balloon treatment for urethral stricture disease: Interim results from the ROBUST I study

INTRODUCTION

We aimed to investigate the safety and preliminary efficacy of the Optilume™ paclitaxel-coated balloon for the treatment of recurrent urethral stricture.

METHODS

Men with bulbar urethral strictures ≤2 cm with 1-4 prior endoscopic treatments were enrolled at four study sites after ethics committee approvals. All subjects were treated with mechanical balloon dilation or direct visualization internal urethrotomy prior to drug-coated balloon treatment. Patients were evaluated at 2-5 days, 14 days, three, six, and 12-months post-treatment. The primary safety endpoint was serious complications through 90 days post-procedure. The preliminary efficacy endpoint was anatomic success, defined as urethral lumen ≥14 Fr at 12 months.

RESULTS

A total of 53 subjects were enrolled and treated; 46 completed the 12-month followup. Forty-three percent of men had undergone >1 previous dilation; the mean for the overall study population was 1.7 prior dilations. There were no serious adverse events related to the treatment within 90 days. Anatomic success was achieved in 32/46 (70%; 95% confidence interval [CI] 54-82%) at 12 months. The 14 failures included seven cystoscopic recurrences, five retreatments, and two patients who exited the study early due to symptom recurrence.

CONCLUSIONS

One-year data indicates the Optilume paclitaxel-coated balloon is safe for the treatment of recurrent bulbar urethral strictures. Early efficacy results are encouraging and support further followup of these men through five years, as well as further investigation with a randomized trial.

Intralesional Steroid Injections for Recurrent Vaginal Strictures

BACKGROUND

Postoperative complications after transverse vaginal septum excision include stricture formation. The purpose of this report is to describe use of intralesional corticosteroid injections for vaginal strictures.

CASE

A 32-year-old gravida 0 with history of transverse vaginal septum and recurrent strictures presented for follow-up of chronic pelvic pain. After her fourth septum revision, the patient underwent a total of 7 triamcinolone injections at the septum tissue. The course of triamcinolone injections improved the stricture and patient's pain.

SUMMARY AND CONCLUSION

Steroid injection into the vaginal septum tissue can be a safe and effective adjuvant therapy after septum resection. Although it is an established adjuvant therapy in other specialties, further studies are warranted to show a decrease in the recurrence rate of vaginal strictures.

Development of a novel indwelling catheter for urethral surgery

This study aimed to develop an indwelling catheter that can be used for urethral flushing, urethral secretion drainage, local urethral drug delivery, and urine drainage.We designed a new indwelling catheter type that has a balloon, 4 peripheral grooves, and a C-shaped groove on its surface. In addition, there is a flushing channel, a balloon channel, and a urine drainage channel in the catheter body. However, the most critical characteristic is that the flushing channel and the 4 peripheral grooves are connected with the C-shaped groove, and the flushing liquid can reach the C-shaped groove through the flushing channel and then flow out through the peripheral grooves, while the balloon channel leads to the balloon. Generally, our design is to add 4 peripheral grooves, a C-shaped groove, and a flushing channel to the indwelling catheter that is applied clinically nowadays.We designed a new type of indwelling catheter, which is multifunctional, and we had acquired a national patent in China. In theory, the new catheter type cannot only be used for urine drainage, bladder irrigation, but also for urethral flushing, urethral excretion drainage, and local urethral drug delivery at the same time.This new indwelling catheter can theoretically reduce catheter-associated urinary tract infection and facilitate urethral secretion drainage or flushing out, which is especially suitable for the treatment and nursing of patients who underwent urethral operation. However, the new catheter have not been produced and tested clinically, and this is our next step.

microRNA expression profiles of scar and normal tissue from patients with posterior urethral stricture caused by pelvic fracture urethral distraction defects

Pelvic fracture urethral distraction defect (PFUDD) seriously affects the quality of life of patients. At present, there are few effective drug treatments available for PFUDD-induced urethral stricture, which is associated with fibrosis and scar formation in urethra lumen. Emerging evidence suggests that microRNAs (miRNAs/miRs) may be involved in the regulation of fibrosis, and analysis of miRNA expression profiles in urethral scar and normal urethra tissues may therefore benefit the discovery of novel treatments for urethral stricture with micro invasive procedures. In the present study, miRNA sequencing and quantitative polymerase chain reaction (qPCR) validation using paired scar and normal tissues from patients with PFUDD, and functional analysis of the miRNAs involved in the fibrosis associated signaling pathway was performed. A total of 94 differentially expressed miRNAs were identified in the scar tissue of patients with PFUDD. Among them, 26 miRNAs had significantly altered expression in the scar tissue compared with the normal tissue from the same patient. qPCR validation confirmed that miR-129-5p was overexpressed in scar tissue. The TGF-β pathway-associated functions of a total of 5 miRNAs (hsa-miR-129-5p, hsa-miR-135a-5p, hsa-miR-363-3p, hsa-miR-6720-3p and hsa-miR-9-5p) were further analyzed, as well as their key molecular targets and functional mechanisms in signaling regulation. To conclude the miRNA sequencing indicated a significantly altered expression of hsa-miR-129-5p, hsa-miR-135a-5p, hsa-miR-363-3p, hsa-miR-6720-3p and hsa-miR-9-5p in patients with PFUDD. These miRNAs and their potential target genes were associated with fibrosis in several diseases, and the data from the present study may help explore potential miRNA targets for future precision treatments for urethral stricture.

The predictive value of platelet to lymphocyte and neutrophil to lymphocyte ratio in determining urethral stricture after transurethral resection of prostate

OBJECTIVE

The pathology of urethral stricture disease is still unclear however progressive inflammation may contribute to the development of urethral stricture. The platelet-to- lymphocyte ratio (PLR) is a new and simple marker that indicates inflammation. In this study we aimed to investigate the predictive value of neutrophil to lymphocyte ratio (NLR) and PLR in patients with urethral stricture who underwent transurethral resection of prostate (TURP).

MATERIAL AND METHODS

A total of 208 patients who underwent bipolar-TURP were included in this study. Patients who had previously undergone surgery due to any urethral pathology, posterior urethral strictures, previous or ongoing treatment for any cancer, hematologic disorders, presence of an active infection at the time of surgical intervention, and prior blood transfusion were excluded. PLR, NLR and red cell distribution width (RDW) levels were measured. In order to investigate the predictive values of NLR and PLR variables, binary logistic regression analysis was performed.

RESULTS

No statistically significant differences were observed between the groups in terms of age, NLR, RDW, prostate size and operative times. Statistically significant differences were presented only in the median PLR- values. For predicting urethral stricture, the optimal cut-off value was 112.5, (sensitivity: 0.84, specificity: 0.64; AUC=0.762, 95% CI 0.684-0.84).

CONCLUSION

In this study we showed that PLR can be used to determine urethral stricture as a cost-effective, common, and simple biomarker in patients after TURP.

Management of bladder neck stenosis and urethral stricture and stenosis following treatment for prostate cancer

The aim of this review is to examine all urethral strictures and stenoses subsequent to treatment for prostate cancer, including radical prostatectomy (RP), radiotherapy, high intensity focused ultrasound (HIFU) and cryotherapy. The overall majority respond to endoscopic treatment, including dilatation, direct visual internal urethrotomy (DVIU) or bladder neck incision (BNI). There are adjunct treatments to endoscopic management, including injections of corticosteroids and mitomycin C (MMC) and urethral stents, which remain controversial and are not currently mainstay of treatment. Recalcitrant strictures are most commonly managed with urethroplasty, while recalcitrant stenosis is relatively rare yet almost always associated with bothersome urinary incontinence, requiring bladder neck reconstruction and subsequent artificial urinary sphincter (AUS) implantation, or urinary diversion for the devastated outlet.

Application of Wnt Pathway Inhibitor Delivering Scaffold for Inhibiting Fibrosis in Urethra Strictures: In Vitro and in Vivo Study

Objective: To evaluate the mechanical property and biocompatibility of the Wnt pathway inhibitor (ICG-001) delivering collagen/poly(l-lactide-co-caprolactone) (P(LLA-CL)) scaffold for urethroplasty, and also the feasibility of inhibiting the extracellular matrix (ECM) expression in vitro and in vivo. Methods: ICG-001 (1 mg (2 mM)) was loaded into a (P(LLA-CL)) scaffold with the co-axial electrospinning technique. The characteristics of the mechanical property and drug release fashion of scaffolds were tested with a mechanical testing machine (Instron) and high-performance liquid chromatography (HPLC). Rabbit bladder epithelial cells and the dermal fibroblasts were isolated by enzymatic digestion method. (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay) and scanning electron microscopy (SEM) were used to evaluate the viability and proliferation of the cells on the scaffolds. Fibrolasts treated with TGF-β1 and ICG-001 released medium from scaffolds were used to evaluate the anti-fibrosis effect through immunofluorescence, real time PCR and western blot. Urethrography and histology were used to evaluate the efficacy of urethral implantation. Results: The scaffold delivering ICG-001 was fabricated, the fiber diameter and mechanical strength of scaffolds with inhibitor were comparable with the non-drug scaffold. The SEM and MTT assay showed no toxic effect of ICG-001 to the proliferation of epithelial cells on the collagen/P(LLA-CL) scaffold with ICG-001. After treatment with culture medium released from the drug-delivering scaffold, the expression of Collagen type 1, 3 and fibronectin of fibroblasts could be inhibited significantly at the mRNA and protein levels. In the results of urethrography, urethral strictures and fistulas were found in the rabbits treated with non-ICG-001 delivering scaffolds, but all the rabbits treated with ICG-001-delivering scaffolds showed wide caliber in urethras. Histology results showed less collagen but more smooth muscle and thicker epithelium in urethras repaired with ICG-001 delivering scaffolds. Conclusion: After loading with the Wnt signal pathway inhibitor ICG-001, the Collagen/P(LLA-CL) scaffold could facilitate a decrease in the ECM deposition of fibroblasts. The ICG-001 delivering Collagen/P(LLA-CL) nanofibrous scaffold seeded with epithelial cells has the potential to be a promising substitute material for urethroplasty. Longer follow-up study in larger animals is needed in the future.

Outcomes of Direct Vision Internal Urethrotomy for Bulbar Urethral Strictures: Technique Modification with High Dose Triamcinolone Injection

Objective. To evaluate the recurrence rate of bulbar urethral strictures managed with cold knife direct vision internal urethrotomy and high dose corticosteroid injection. Methods. 28 patients with bulbar urethral strictures underwent direct vision internal urethrotomy with high dose triamcinolone injection into the periurethral tissue and were followed up for recurrence. Results. Our cohort had a mean age of 60 years and average stricture length of 1.85 cm, and 71% underwent multiple previous urethral stricture procedures with an average of 5.7 procedures each. Our technique modification of high dose corticosteroid injection had a recurrence rate of 29% at a mean follow-up of 20 months with a low rate of urinary tract infections. In patients who failed treatment, mean time to stricture recurrence was 7 months. Patients who were successfully treated had significantly better International Prostate Symptom Scores at 6, 9, and 12 months. There was no significant difference in maximum flow velocity on Uroflowmetry at last follow-up but there was significant difference in length of follow-up (p = 0.02). Conclusions. High dose corticosteroid injection at the time of direct vision internal urethrotomy is a safe and effective procedure to delay anatomical and symptomatic recurrence of bulbar urethral strictures, particularly in those who are poor candidates for urethroplasty.

Steroid Administration is Effective to Prevent Strictures After Endoscopic Esophageal Submucosal Dissection: A Network Meta-Analysis

Esophageal stricture is a severe adverse event after circumferential endoscopic submucosal dissection (ESD). Steroid administration is a new method to prevent stricture formation. We performed a meta-analysis to investigate the efficacy and safety of steroid administration to prevent esophageal stricture after circumferential ESD. PubMed, the Cochrane Library, EMBASE, Chinese Biomedical Database, and Clinicaltrials.gov were searched. Studies on steroid administration + endoscopic balloon dilation (EBD) versus EBD alone for esophageal stricture were included and pooled analyzed in random-effects models. Besides, subgroup analysis and network analysis were performed to define the influence of ESD type and steroid administration method. Twelve studies involving 513 patients were included. Meta-analysis showed that steroid administration significantly achieved a lower stricture rate (risk ratio [RR], 0.40; 95% CI, 0.20-0.81) and less required EBD sessions (mean difference [MD], -4.33; 95% CI, -6.10 to -2.57) than control. Subgroup analysis indicated that steroid was effective after both semi- and complete circumferential ESD. Network meta-analysis showed that compared with oral steroid, local injected steroid had a similar effect to prevent stricture (RR, 1.16; 95% CI, 0.48-2.85), whereas a better effect to reduce required EBD sessions (MD, 7.77; 95%CI, 0.26-15.3). Additional steroid administration is effective to reduce the stricture rate and required EBD sessions. And local injected steroid was superior to oral steroid in EBD reduction, whereas due to the varied method and dose of steroid administration, the finding needs to be clarified in the future.

Collagenase Clostridium histolyticum (Xiaflex) for the Treatment of Urethral Stricture Disease in a Rat Model of Urethral Fibrosis

OBJECTIVE

To evaluate the treatment effect of collagenase Clostridium histolyticum (CCH) in a rat model of urethral fibrosis.

MATERIALS AND METHODS

Thirty male Sprague-Dawley rats (300-350 g) were divided into 5 groups. The rat urethra was injected with normal saline in the sham group and, in the other 4 groups, the rat urethra was injected with 10 μg of transforming growth factor beta 1 to create fibrosis of the urethra. Two weeks following transforming growth factor beta 1 injection, the rats were injected with varying doses of CCH or vehicles, depending on their group. The rats were then euthanized at 4 weeks after CCH or vehicle injection. Urethral tissue was harvested for histologic and molecular analyses. Type I and III collagen levels were evaluated by Western blot analysis.

RESULTS

There was urethral fibrosis and to significant increase in collagen type I and III expressions in the urethral fibrosis group compared with the sham group (P <.05). Urethral injection of CCH appeared to be safe and significantly reduce urethral fibrosis as well as collagen type I and III expressions in the high-dose CCH treatment groups when compared with the treatment control group (P <.01).

CONCLUSION

This study demonstrated a beneficial effect of CCH injections in a rat model of urethral fibrosis. These findings suggest a potential role for CCH as a therapeutic option in urethral stricture patients and warrant further investigation.