Stricture Disease Research Articles

Preoperative Predictors of Surgical Success for Robotic Ureteral Reconstruction of Proximal and Middle Ureteral Strictures

OBJECTIVETo investigate predictors of surgical success for patients undergoing robotic ureteral reconstruction (RUR) for ureteropelvic junction obstruction, proximal and middle ureteral stricture disease. METHODSWe retrospectively reviewed our multi-institutional Collaborative of Reconstructive Robotic Ureteral Surgery (CORRUS) database to identify all consecutive patients undergoing RUR for UPJO, proximal and/or middle ureteral stricture disease between 04/2012-12/2020. The specific reconstruction technique was determined by the primary surgeon based on clinical history and intraoperative findings. Patients were grouped according to whether they were surgical successful. Preoperative variables between both groups were compared using chi-square tests. All independent variables with associations of p<0.2 then underwent a binary logistic regression analysis to determine predictive variables of success for RUR (p≤0.05 was considered statistically significant). RESULTSOverall, 338 patients met inclusion criteria. Surgical success rates of RUR are shown in Table 1. Univariate analysis (Table 2) showed that there were a lower proportion of patients with diabetes (8.9% versus 25.7%, p<0.01) and a higher proportion of patients who underwent ureteral rest (74.3% versus 48.6%, p<0.01) in the surgical success group. Multivariate logistic regression analysis (Table 3) further revealed the odds of surgical success in patients without diabetes was 3.08 times (CI 1.26-7.54, p=0.01) the odds of success for patients with diabetes. The odds of surgical success in patients who underwent preoperative ureteral rest were 2.8 times (CI 1.35-5.83, p=0.01) the odds of success for patients who did not undergo preoperative ureteral rest. CONCLUSIONSurgical success of RUR for management of UPJO, proximal and middle ureteral strictures may be influenced by factors including preoperative ureteral rest and presence of diabetes.

Epigenetic and Metabolic Reprogramming of Fibroblasts in Crohn's Disease Strictures Reveals Histone Deacetylases as Therapeutic Targets.

No effective therapeutic intervention exists for intestinal fibrosis in Crohn's disease [CD]. We characterized fibroblast subtypes, epigenetic and metabolic changes, and signalling pathways in CD fibrosis to inform future therapeutic strategies. We undertook immunohistochemistry, metabolic, signalling pathway and epigenetic [Transposase-Accessible Chromatin using sequencing] analyses associated with collagen production in CCD-18Co intestinal fibroblasts and primary fibroblasts isolated from stricturing [SCD] and non-stricturing [NSCD] CD small intestine. SCD/NSCD fibroblasts were cultured with TGFβ and valproic acid [VPA]. Stricturing CD was characterized by distinct histone deacetylase [HDAC] expression profiles, particularly HDAC1, HDAC2, and HDAC7. As a proxy for HDAC activity, reduced numbers of H3K27ac+ cells were found in SCD compared to NSCD sections. Primary fibroblasts had increased extracellular lactate [increased glycolytic activity] and intracellular hydroxyproline [increased collagen production] in SCD compared to NSCD cultures. The metabolic effect of TGFβ stimulation was reversed by the HDAC inhibitor VPA. SCD fibroblasts appeared 'metabolically primed' and responded more strongly to both TGFβ and VPA. Treatment with VPA revealed TGFβ-dependent and TGFβ-independent Collagen-I production in CCD-18Co cells and primary fibroblasts. VPA altered the epigenetic landscape with reduced chromatin accessibility at the COL1A1 and COL1A2 promoters. Increased HDAC expression profiles, H3K27ac hypoacetylation, a significant glycolytic phenotype and metabolic priming characterize SCD-derived as compared to NSCD fibroblasts. Our results reveal a novel epigenetic component to Collagen-I regulation and TGFβ-mediated CD fibrosis. HDAC inhibitor therapy may 'reset' the epigenetic changes associated with fibrosis.

S14 Impact of Body Mass Index as Predictor for Surgical Interventions in Crohn’s Disease Strictures

S14 Impact of Body Mass Index as Predictor for Surgical Interventions in Crohn’s Disease Strictures

Uropathogenic Dysbiosis Pattern is Associated With Urethral Fibrosis

Purpose: Cellular mechanisms of stricture progression after repeated transurethral interventions are unclear. We hypothesize that urethral injury and mechanical stretch cause tears on the urethral epithelial cell lining leading to leaking epithelium and urine extravasation. Urinary bacteria traverse the epithelial lining and may promote fibrogenesis through inflammation due to microbial activity. Our objective was to perform a case-control study of the urobiome from patients with urethral stricture disease or healthy controls using 16S rRNA and shotgun metagenomic sequencing profiling to elucidate the clinical relevance of the urobiome in urinary stricture progression. Materials and Methods: First catch urine samples from patients and healthy volunteers were collected and pelleted urine was used for DNA extraction, followed by high throughput 16S rRNA and shotgun metagenomic sequencing. Sequencing data were used to determine microbial taxa and functions associated with urethral stricture disease. Results: Sequencing results revealed that the lower urinary tract urobiome was significantly different between urethral stricture disease cases and healthy controls. In particular, taxonomic and metabolic profiles point toward anaerobic biofilm formation by antibiotic-resistant species of Klebsiella, which is a known uropathogen. Importantly, no patients in the study exhibited signs or symptoms of clinical infection. Conclusions: Our findings suggest a role for biofilm formation by uropathogens such as Klebsiella spp. in developing an inflammatory environment and consequent fibrosis progression. Future studies will elucidate specific mechanisms of Klebsiella-induced fibrosis. Our data suggest that targeting specific bacteria or biofilm formation may be beneficial for urethral stricture disease detection and prevention of progression.

Extracellular matrix analysis of fibrosis: A step towards tissue engineering for urethral stricture disease.

The urogenital tract is a target for many congenital and acquired diseases, both benign and oncogenic. In males, the urethra that transports urine and semen can be obstructed by a fibrotic disease called urethral stricture disease (USD). In severe USD, the whole organ including the vascular embedding, the corpus spongiosum (CS), is affected. Recurrent or severe USD is treated by reconstructive surgery. Tissue engineering may improve the outcome of urethral reconstruction in patients with complicated USD. Currently in urethral reconstruction only the epithelial layer is replaced, no substitution for the CS is provided, while the CS is important for mechanical support and vascularization. To develop a tissue engineering strategy for the CS, it is necessary to know the protein composition of the CS. As the extracellular matrix (ECM) plays an important role in the formation of fibrosis, we analyzed the distribution and localization of ECM components in human healthy and fibrotic CS tissue using immunohistology. The morphology of components of the elastic network were affected in USD. After decellularization a clear enrichment of proteins belonging to the ECM was found. In the proteomic analysis collagens COL15A1 and COL4A2 as well as inter-alpha-trypsin inhibitor ITIH4 were upregulated in fibrotic samples. The glycoproteins Periostin (POSTN), Microfibrillar-associated protein 5 (MFAP5) and EMILIN2 are downregulated in fibrotic tissue. To our knowledge this is the first proteomic study of ECM proteins of the CS in healthy and in USD. With these results a regenerating approach for tissue engineered CS can be developed, including relevant ECM proteins that reduce fibrosis and promote healthy healing in urethral reconstructive surgery.

Long-term outcomes of urethral balloon dilation for anterior urethral stricture: A prospective cohort study

ObjectiveTo prospectively follow up a cohort of anterior urethral stricture disease patients managed with balloon dilation (BD) for 3 years to evaluate the long-term outcomes and to study factors that contribute to recurrence. MethodsThis study included men who had urethral BD for significant anterior urethral stricture disease between January 2017 and March 2019. Data about the patient age, stricture characteristics, and recurrence date were recorded, along with information on postoperative indwelling catheter use and operative complications. Furthermore, information about the self-calibration procedure was collected and where available, free flow (FF) measurements during the follow-up period were recorded and analyzed. Success was defined as a lack of symptoms and acceptable FF rates (maximum flow rate>12 mL/s). ResultsThe final analysis was conducted on 187 patients. The mean follow-up period was 37 months. The long-term overall success rate at the end of our study was 66.8%. Our recurrence rate was 7.4% at 12 months, 24.7% at 24 months, and reached 33.2% at the end of our study. The time to recurrence ranged from 91 days to 1635 days, with a mean of 670 days. The stricture-free survival was significantly shorter with lengthy peno-bulbar (p=0.031) and multiple strictures (p=0.015), and in the group of patients who were not committed to self-calibration protocol (p<0.011). However, post-procedural self-calibration was the most important factor that may have decreased the incidence of recurrence (odds ratio=5.85). Adjuvant self-calibration after BD not only reduced the recurrence rate from 85.4% in the non-self-calibration group to 15.1% in the self-calibration one (p<0.001), but also improved the overall stricture-free survival and FF parameters. ConclusionUrethral BD has a high recurrence rate in the long-term, especially with long and multiple strictures. Adjuvant self-calibration has proven to reduce the recurrence risk and the need for re-intervention.

Three Optilume® drug-coated balloon dilations in series for panurethral stricture disease

Three Optilume® drug-coated balloon dilations in series for panurethral stricture disease

Single-stage or two-stage? Experience from single center for lichen sclerosus-related urethral stricture disease

Single-stage or two-stage? Experience from single center for lichen sclerosus-related urethral stricture disease

Qualitative Analysis of Patient Experiences Reaching Urethroplasty for Recurrent Urethral Stricture Disease.

Despite the inferior outcomes, urethral stricture patients often undergo multiple endoscopic procedures prior to undergoing definitive urethroplasty. We sought to qualitatively evaluate the patient experience of obtaining urethroplasty to better understand the impact of this experience on quality of life. Patients treated with urethroplasty between September 2019 and July 2021 were identified and invited to participate in our study if they had undergone ≥ 2 endoscopic procedures prior to urethroplasty. Semistructured telephone interviews were conducted, coded, and analyzed using an iterative inductive-deductive approach. Of the 105 urethroplasty patients during the study period, 50 (47.6%) had undergone ≥ 2 endoscopic procedures prior (IQR 3-5), of whom 20 participated in the study. Qualitative themes related to repeat endoscopic procedures included unmet treatment expectations, dissatisfaction with catheterization and repeat procedures, and negative impacts of recurrent stricture symptoms and treatments on quality of life. External factors associated with a delay to urethroplasty included financial constraints, surgeon access, and time off work. A trajectory of declining quality of life and unmet treatment expectations are the primary factors driving the decision to proceed with urethroplasty. However, external factors such as recovery costs and access to specialists play important roles in delaying surgery. These findings illustrate the need for improved community provider education and patient counseling to better inform expectations of both patients and providers with various treatment outcomes. Furthermore, these data highlight the need to improve access to specialized care for urethral stricture patients.

Novel Urethral Stricture Disease Guideline Amendment (2023) by the American Urological Association: editorial comments

This article summarises the new amendments to the American Urological Association guidelines on Urethral Stricture Disease (2023) and comments thereon. The author presents a view on a few issues based on the experience of management more than 10.000 patients with urethral strictures.

Serial Changes in Intestinal Stenotic Stiffness in Patients with Crohn's Disease Treated with Biologics: A Pilot Study Using Ultrasound Shear Wave Elastography.

Intestinal strictures represent an important serious complication of Crohn's disease. Shear wave elastography is a promising noninvasive ultrasound technique for assessing tissue stiffness. This study aimed to evaluate stiffness in the areas of intestinal stricture in patients with Crohn's disease using shear wave elastography and the changes in stiffness after biologics. We enrolled 21 Crohn's disease patients having intestinal stricture. The patients consisted of 3 groups, which were the infliximab naïve (n = 6) group, the ustekinumab naïve (n = 8), and the bio-switch from infliximab to ustekinumab (n = 7) group. Bowell wall thickness was examined by ultrasound sonography, and the stiffness of Crohn's disease stricture lesions was evaluated using Shear wave speed before and 1 year after anti-tumor necrosis factor-alpha antibody infliximab, anti-interleukin 12/23 antibody ustekinumab, and bio-switch from infliximab to ustekinumab. Bowell wall thickness was significantly improved after infliximab, ustekinumab, and the bio-switch. However, shear wave speed indices only in the ustekinumab group significantly decreased after treatment (P = .028), but not in the other group. Shear wave elastography might be a useful method to evaluate stiffness in the areas of intestinal stricture in patients with Crohn's disease treated with biologics. However, a prospective randomized study evaluating the development of obstruction after biological treatment is needed to validate the study findings.

De novo urethral stricture disease in renal transplant recipients.

With routine catheterization and low urine output pre-transplant, renal transplant recipients (RTRs) may be at risk of urethral stricture disease post-transplant. The objective of this study was to characterize new urethral stricture disease in males following renal transplant. A retrospective chart review was carried out on all male RTRs at Vancouver General Hospital who developed urethral strictures from October 2009-2019. Descriptive analyses were conducted on patient characteristics. Comparative analyses against non-stricture RTRs were carried out. Of 636 RTRs, 18 (2.8%) developed a postoperative urethral stricture. Median time from transplant to stricture discovery was 56 days (range 8-618 days). One-third of stricture patients had prior risk factors for stricture formation. Post-transplant, 77.8% presented symptomatically, with 61.1% requiring intervention. Overall graft survival rate was 88.9% among the RTR stricture group; 16.7% experienced acute rejection and 22.2% had delayed graft function (DGF). There was no significant association between developing postoperative urethral stricture and urinary tract infection (Chi-squared [X2]=0.04, p=0.84; odds ratio [OR ] 0.81, 95% confidence interval [CI] 0.1-6.21), DGF (X2=0.14, p=0.70; OR 0.8, CI 0.26-2.48), or acute rejection (X2=2.02, p=0.14; OR 2.55, CI 0.71-9.12). De novo post-transplant urethral stricture rates appear to occur at a higher rate than the general population and contribute to patient morbidity. Stricture disease should be considered post-transplantation in patients with voiding dysfunction, even if they don't have prior risk factors. Multicenter studies should be considered to elucidate any relationship between urethral stricture and graft survival.

Retrograde sagittal urethrography in diagnostics of urethral stricture disease: shifting the focus

Background. For over a century retrograde urethrography (RUG) has offered the key method to diagnose urethral stricture (US). The disadvantage of the technique, however, is a potential high risk to underestimate the stricture length due to distorted visualization and eventual flawed surgical planning.Aim. To consider retrograde sagittal urethrography (RSU) and how it contributes to enhancing US preoperative diagnostics and treatment efficacy in clinical practice.Materials and methods. We compared the protocols of pre-op urethrograms performed by a radiologist and a urologist to surgery protocols for both patient groups. Group 1 included 154 patients who underwent US surgical treatment from 2017 to 2021 after using RSU as a diagnostic method (positioning 90°). Group 2 comprised 142 patients presented with identical disease who received surgery between 2012 to 2016 in our hospital after RUG using traditional technique (positioning 45°). Discrepancies of 5 mm and over in stricture length measurements between radiography protocols and intraoperative data were considered a diagnostic flaw (i.e. inconsistency). Treatment efficacy was compared across both groups.Results. In 87.6 % of cases in Group 1 (RSU) protocols provided by a radiologist matched intraoperative data versus45.7 % of cases receiving accurate protocol data in Group 2 (RUG) (χ2 = 59.15, p &lt;0.001). Urethrogram protocols prepared by a urologist pre-operatively were accurate in 95.4 % of cases in Group 1 versus 62.0 % in Group 2 (χ2 = 49.11, p &lt;0.001). The overall efficiency of surgery was higher in Group 1 (91.6 %), than in Group 2 (82.4 %) (χ2 = 5.54, p &lt;0.01).Conclusion. RSU is an innovative technique that allows to significantly improve the accuracy of urethral stricture length measurement, resulting in greater treatment efficiency in Group 1 of patients. The proposed urethrographic technique can be recommended as a basic diagnostic procedure for anterior US in men.

Outcomes of Urethroplasty for Synchronous Anterior Urethral Stricture Utilizing the Trauma and Urologic Reconstruction Network of Surgeons Length, Segment and Etiology Anterior Urethral Stricture Classification System

To describe the characteristics, management, and functional outcomes of patients with synchronous urethral stricture disease (SUSD) utilizing a multi-institutional cohort. Data were collected and assessed from a prospectively maintained, multi-institutional database. Patients who underwent anterior urethroplasty for urethral stricture disease (USD) were included and stratified by the presence or absence of SUSD. USD location and etiology were classified according to the Trauma and Urologic Reconstruction Network of Surgeons Length, Segment and Etiology Anterior Urethral Stricture Classification System. Anterior urethroplasty techniques were recorded for both strictures. Functional failure was compared between groups. One thousand nine hundred eighty-three patients were identified, of whom, 137/1983 (6.9%) had SUSD. The mean primary stricture length for patients with SUSD was 3.5 and 2.6cm for the secondary stricture. Twelve anterior urethroplasty technique combinations were utilized in treating the 27 different combinations of SUSD. Functional failure was noted in 18/137 (13.1%) patients with SUSD vs 192/1846 (10.4%) patients with solitary USD, P=.3. SUSD was not associated with increased odds of functional failure. S classifications: S1b, P=.003, S2a, P=.001, S2b, P=.01 and S2c, P=.02 and E classifications: E3a, P=.004 and E6, P=.03, were associated with increased odds of functional failure. Repair of SUSD in a single setting does not increase the risk of functional failure compared to patients with solitary USD. Increasing S classification, S1b through S2c and E classifications E3a and E6 were associated with increased functional failure. This reinforces the importance of the Trauma and Urologic Reconstruction Network of Surgeons Length, Segment and Etiology Anterior Urethral Stricture Classification System as a necessary tool in large-scale multi-institutional analysis when assessing highly heterogenous patient populations.

Management Patterns of Male Urethral Stricture Disease among Urologists: What Do the Guidelines Say? What Do Urologists Do?

The aim of the present study is to evaluate and analyze the daily clinical practice for male urethral stricture disease (MUSD) among urologists. Considering the latest guidelines on urethral stricture disease, a survey was developed regarding the various treatment options and preferences in different sites of male urethral stricture disease. The survey was sent to urologists via e-mail and phone application. A total of 266 urologists completed the survey and were included in the final analysis. In regard to workplace, 62 (23.3%), 58 (21.8%), 71 (26.7%), and 75 (28.2%) respondents worked in university hospitals, training and research hospitals, state hospitals, and private practice hospitals, respectively. In regard to the diagnostic method used in male urethral strictures, 88.7% of the participants would choose uroflowmetry + postvoiding residual (UF + PVR), and 64.6% would choose retrograde urethrography (RUG). Direct vision internal urethrotomy (DVIU) was the most frequently chosen method in penile urethral strictures (PUS), being chosen by 72.9%. Direct vision anterior internal urethrotomy was the most common method for both ≤2 cm and >2 cm strictures, 63.1%, and 30.8%, respectively. The most preferred graft for augmentation urethroplasty was buccal mucosa (75.8%). Endoscopic incision/resection (transurethral resection (TUR)) is the most frequently applied treatment method for posterior urethral/vesicourethral anastomotic strictures (86.4%). The present study clearly shows that most urologists still prefer DVIU and urethral dilatation to urethroplasty in MUSD, which contradicts current guidelines. Urologists should be encouraged to perform urethroplasty and/or refer patients to experienced centres for recurrent MUSD.

Understanding the prevalence and distribution of fellowship trained female and male genitourinary reconstruction and men's health/andrology academic faculty in the United States.

We evaluated the prevalence, distribution, and specialist to population ratio of male and female reconstruction and andrology/prosthetics faculty within United States urologic training programs. Our objective was to help determine the current need/demand for reconstructive fellowship trained faculty for necessary clinical exposure during residency in the midst of a nationwide residency expansion. All non-military urology residency programs were evaluated. Programs were sorted into their American Urologic Association Sections and websites were analyzed for evidence of fellowship training and/or clinical expertise/interest: (I) male genitourinary reconstruction (MGR); (II) female genitourinary reconstruction (FGR) and (III) infertility/andrology/men's health (AMH). The 2020 US Census data was used to determine specialist to population ratios by sections. Of 137 evaluated programs, FGR had the highest percentage of fellowship-trained faculty (76%) followed by AMH (66%) and MGR (61%). Clinical/surgical interest was noted in pelvic organ prolapse (88%), inflatable penile prosthesis (79%) and urethral stricture disease (75%). Over 10% of training programs had two or more faculty with MGR, FGR and AMH fellowship training. Significant geographic variation amongst academic programs exists with the South and Southeastern parts of the US being relatively underserved, both in percentage of programs with fellowship-trained faculty, and by faculty per 1,000,000 inhabitants. The majority of US urology residencies have faculty with fellowship training and/or stated clinical interest in MGR, FGR and AMH. Still, many programs remain without these faculty while others have two or more in their respective fields. The geographic trends noted here have both educational and recruitment significance.

To assess the impact of prior urethral dilatation or DVIU on the outcome of anterior urethroplasty.

Background: Male urethral stricture has remained the major problem in urologic practice. Patients presenting with urethral stricture disease are commonly managed by dilatation, DVIU, and urethroplasty.&#x0D; Methodology: This is a descriptive study of male patients who underwent anterior urethroplasty at our setup from 5th August 2021 to 25th February 2022. We analyzed the age, duration, type, length, and location of the stricture and the surgical treatment outcome after urethroplasty. The post-operative catheter was removed after 3 weeks, and UFM is advised. Qmax (max flow rate) &gt; 15 ml/sec was measured on UFM (uroflowmetry) on the 1st week, 6 weeks, and followed on 3 months. Final outcome in terms of success was assessed by uroflowmetry. A maximum urine flow greater than 15mL/s after 3 months’ treatment assessed by uroflowmetry was considered as success.&#x0D; Results: In our study, the blood loss in group A and group B patients, those patients who had DVIU or dilation in the past, had more bleeding during surgery than those who did not have a history of surgery. 66.67% of group B patients have bleeding from 200 ml to 500 ml, which is higher than group A patients. In our study, we found that if the patient had undergone surgery or no surgery had taken place before urethroplasty, the results in terms of UFM were quite similar, as in group A, 96.69% of patients had UFM more than 15 ml/sec, and in group B 87.88% had UFM more than 15 ml/sec.&#x0D; Conclusion: Urethral dilatation or DVIU delays definitive treatment and increases operative challenges by increasing the length of stricture, more adhesion, and more fibrosis but has minimal impact on the outcome of urethroplasty success.

Preoperative stricture length measurement does not predict postoperative outcomes in robotic ureteral reconstructive surgery.

We sought to determine whether preoperative stricture length measurement affected the choice of procedure performed, its correlation to intraoperative stricture length, and postoperative outcomes. The Collaborative of Reconstructive Robotic Ureteral Surgery (CORRUS) database was queried for patients undergoing robotic ureteral reconstructive surgery from 2013 to 2021 who had surgical stricture length measurement. From this cohort, we identified patients with and without preoperative stricture length measurement via retrograde pyelogram or antegrade nephrostogram. Outcomes evaluated included intraoperative complications, 30-day complications greater than Clavien-Dindo grade II, hardware-free status, and need for additional procedures. Of 153 patients with surgical stricture length measurements, 102 (66.7%) had preoperative radiographic measurement. No repair type was more likely to have preoperative measurement. The Pearson correlation coefficient between surgical and radiographic stricture length measurements was + 0.79. The average surgical measurement was 0.71cm (± 1.52) longer than radiographic assessment. Those with preoperative imaging waited on average 5.0months longer for surgery, but this finding was not statistically significant (p = 0.18). There was no statistically significant difference in intraoperative complications, 30-day complication rates, hardware-free status at last follow-up, or need for additional procedures between patients with and without preoperative measurement. The only significant predictive factor was preoperative stricture length on 30-day postoperative complications. Despite relatively high prevalence of preoperative radiographic stricture length measurement, there are few measures where it offers clinically meaningful diagnostic information towards the definitive surgical management of ureteral stricture disease.

Novel single-stage preputial spiral graft for panurethral stricture: a step-by-step description of the technique.

To report the 12-month results of a novel urethroplasty technique relying on a spiral preputial graft for panurethral stricture disease. Twenty consecutive patients were treated between May and October 2021 at our center. A spiral preputial mucocutaneous graft is a foreskin-based graft, developed from a 5-cm-wide preputial skin, which is harvested using a helicoidal shape and can reach up to 20cm in length. Stricture characteristics were assessed through preoperative retrograde and voiding cystourethrogram and maximum uroflowmetry data (Qmax). Complications were collected up to 30days after surgery and graded using the Clavien-Dindo (C-D) classification. The patients were followed up to 12months. Preoperative median Qmax was 6.5ml/s [interquartile range (IQR): 4.0-8.7]. After a median follow-up of 12months (IQR 12-13), six patients experienced at least one complication. Of them, two patients had grade 2 C-D complications, while only one developed a grade 3a C-D complication. The median postoperative Qmax was 16ml/s (IQR: 13-18). Only one patient had early urethral stricture recurrence treated with dilatation after catheter removal. At one-year follow-up, no other patients had urethral stricture recurrence with an overall median Qmax of 15.1ml/s (IQR 13.5-16.4). Our novel single-stage spiral preputial graft urethroplasty for panurethral stricture treatment appears to be safe and could be used as a valid alternative to two-stage procedures or even to single-stage buccal mucosa graft augmentation.

Urinary microbiome differences between lichen sclerosus induced and non-lichen sclerosus induced urethral stricture disease.

To describe differences in the urinary microbiome of patients with pathologically confirmed lichen sclerosus (LS) urethral stricture disease (USD) vs non-lichen sclerosus (non-LS) USD pre- and post-operatively. Patients were pre-operatively identified and prospectively followed, all underwent surgical repair and had tissue samples obtained to make a pathological diagnosis of LS. Pre- and post-operative urine samples were collected. Bacterial genomic DNA was extracted. Alpha and beta diversity measurements were calculated and compared. A zero-inflated negative binomial model was utilized to compare taxa abundances between disease status and surgery status. Urine samples were obtained from both cohorts, 69 samples in total: 36 samples were obtained pre-operatively and 33 samples were obtained post-operatively. Ten patients provided both a pre-operative and post-operative urine sample. Twenty-six patients had pathological evidence of LS and 33 patients did not. There was a statistically significant difference in alpha diversity between the pre-operative urine samples of patients with non-LS USD and LS USD, (p = 0.01). There was no significant difference in alpha diversity within post-operative urine samples between patients with non-LS USD and LS USD, (p = 0.1). A significant difference was observed in Weighed UniFrac distances with respect to disease and operative status, (p = 0.001 and 0.002). LS USD have significant alterations in diversity and differential abundance of urine microbiota compared to non-LS USD controls. These findings could be used to guide further investigations into the role of the urinary microbiome in LS USD pathogenesis, severity of presentation, and stricture recurrence.