The postoperative renal function of persistent cloaca patients treated by posterior sagittal anorecto-urethro-vaginopalsty: results of a nationwide survey in Japan.

PURPOSE: We investigated the postoperative renal function in persistent cloaca (PC) patients who underwent posterior sagittal anorecto-urethro-vaginopalsty (PSARUVP) and factors influencing the renal functional outcomes. METHODS: A questionnaire survey was distributed to 244 university and children's hospitals across Japan. Of the 169 patients underwent PSARUVP, 103 patients were enrolled in the present study. Exclusion criteria was patients without data of renal prognosis. RESULTS: The present study showed that renal anomalies (p = 0.09), vesicoureteral reflux (VUR) (p = 0.01), and hydrocolpos (p = 0.07) were potential factors influencing a decline in the renal function. Approximately half of the patients had a normal kidney function, but 45.6% had a reduced renal function (Stage ≥ 2 chronic kidney disease: CKD). The incidence of VUR was significantly higher in the renal function decline (RFD) group than those in the preservation (RFP) group (p = 0.01). Vesicostomy was significantly more frequent in the RFD group than in the RFP group (p = 0.04). Urinary tract infections (p < 0.01) and bladder dysfunction (p = 0.04) were significantly more common in patients with VUR than in patients without VUR. There was no association between the VUR status and the bowel function. CONCLUSIONS: Prompt assessment and treatment of VUR along with bladder management may minimize the decline in the renal function.

[A Case of Urethral Foreign Body from 40 Years Ago with Scrotum Abscess and Urethroscrotal Fistula].

A 70-year-old male came to our clinic with a high fever and left scrotal swelling. Following a diagnosis of left-side epididymitis, antibiotic treatment was started, though the swelling did not improve. Since an additional examination revealed an abscess in the left scrotum, scrotal incision and drainage were performed. Although the symptoms subsided, urine outflow from the incision was observed. The patient then noted that he had inserted a glass ball into the urethral meatus when he was about 30 years old. It was considered that an abscess and fistula had formed due to inflammation caused by the foreign body. Thus a transurethral surgical procedure was used for crushing and removal. The fistula disappeared within three months after the operation and the patient has not been affected by dysuria since that time. Symptoms may appear several years following insertion of a foreign body into the urethra. To the best of our knowledge, the present case is the longest term of indwelling, approximately 40 years, following insertion of a foreign body reported in Japan.

Comparison of outcome of TIP urethroplasty with or without Buck's Fascia repair.

OBJECTIVE: TIP is the most common preformed type of Urethroplasty. The intermediate barrier is used as a waterproofing layer to prevent fistula formation. Many tissues have been utilized as a barrier layer, with varying success rates. The search for a better intermediate layer will continue. In this study, we aim to evaluate the role of Buck's Fascia as a covering for the neo-urethra to prevent fistula formation in patients who underwent Snodgrass Urethroplasty. METHODS: This prospective study was conducted between 2018 and 2022. Patients were randomly assigned to either Group 'A' or Group 'B'. Group A included patients who underwent the Snodgrass procedure with a Buck's Fascia cover, while Group B included patients whose neo-urethra was covered with the dartos flap. These patients were closely monitored for the development of short- and long-term complications in both groups, and the results were recorded. RESULTS: The study involved 164 patients, who underwent midpenile and distal hypospadias repair using the Snodgrass technique. In Group 'A' (84 patients), the neo-urethra was covered with Buck's Fascia, while in Group 'B' (80 patients), the neo-urethra was covered with the dartos flap. The mean age of the children was (23.06 ± 16.12) months in group 'A' & (26.06 ± 14.07) months in group 'B'. mean operating time was (40 ± 11.43) minutes, in Group 'A', and (70 ± 17.43) minutes, in Group 'B'. Meatal stenosis occurred in 3.57% of children in Group 'A' and 10% of patients in Group 'B'. Urethral fistulas were encountered in 2.35% of cases in Group 'A'and 10% in Group 'B'. The difference between the groups was statistically significant.

Right perirenal urinoma and urinothorax in an infant after neonatal ablation of posterior urethral valve: A rare complication diagnosed by pleural aspiration and treated with perinephric drainage: a case report.

OBJECTIVE: Urinothorax and urinoma are rare complications of obstructive uropathy. They might occur due to persistent high back pressure on the renal parenchyma. Urinothorax usually arises while the obstruction exists; in contrast to our case, the child presented after being operated on. He had falsely high creatinine before the operation, which was later explained by creatinine recirculation. CLINICAL PRESENTATION AND INTERVENTION: We are reporting an uncommon case of late presentation of ruptured urinoma in a 2-month-old Kuwaiti male. It led to urinothorax/uroperitoneum that caused respiratory distress and was associated with creatinine recirculation, requiring retroperitoneal perinephric catheter insertion. The child had recovered and was discharged home. CONCLUSION: A high index of suspicion is required to diagnose urinothorax, especially in patients with a history of obstructive uropathy. Aspiration of the pleural effusion will guide you to reach the diagnosis. Creatinine recirculation is rarely described in the literature. Having a patient with urinothorax/uroperitoneum should raise the suspicion of falsely elevated creatinine levels.

Prediction of Robotic Anastomosis Competency Evaluation (RACE) metrics during vesico-urethral anastomosis using electroencephalography, eye-tracking, and machine learning.

Residents learn the vesico-urethral anastomosis (VUA), a key step in robot-assisted radical prostatectomy (RARP), early in their training. VUA assessment and training significantly impact patient outcomes and have high educational value. This study aimed to develop objective prediction models for the Robotic Anastomosis Competency Evaluation (RACE) metrics using electroencephalogram (EEG) and eye-tracking data. Data were recorded from 23 participants performing robot-assisted VUA (henceforth 'anastomosis') on plastic models and animal tissue using the da Vinci surgical robot. EEG and eye-tracking features were extracted, and participants' anastomosis subtask performance was assessed by three raters using the RACE tool and operative videos. Random forest regression (RFR) and gradient boosting regression (GBR) models were developed to predict RACE scores using extracted features, while linear mixed models (LMM) identified associations between features and RACE scores. Overall performance scores significantly differed among inexperienced, competent, and experienced skill levels (P value < 0.0001). For plastic anastomoses, R2 values for predicting unseen test scores were: needle positioning (0.79), needle entry (0.74), needle driving and tissue trauma (0.80), suture placement (0.75), and tissue approximation (0.70). For tissue anastomoses, the values were 0.62, 0.76, 0.65, 0.68, and 0.62, respectively. The models could enhance RARP anastomosis training by offering objective performance feedback to trainees.

[Urethral reconstruction]. / Harnröhrenrekonstruktion.

A urethral stricture is an abnormal narrowing of the urethra due to spongiofibrosis of the urethral mucosa and the underlying corpus spongiosum. The diagnostics include uroflowmetry, sonography and radiology. For penile strictures the success rate of endoscopic treatment is low. Therefore, urethroplasty should always be performed, preferably using oral mucosa. Depending on the complexity, reconstruction must be carried out in one or multiple stages. For short bulbous strictures endoscopic treatment can primarily be carried out. In the case of recurrence urethroplasty should be carried out. The indications for urethral reconstruction are primarily given for long bulbous strictures. Depending on the length and extent of the stricture, a scar resection and end-to-end anastomosis, non-transsecting end-to-end anastomosis or augmentation urethroplasty can be performed. Perineal urethrostomy (the so-called boutonnière procedure) is a treatment option for patients with complex strictures or for patients who want a straightforward solution.

Carcinoma in situ within the bladder trigone with an isolated metastasis to the prostate without involvement of prostatic urethra: a unique case report.

BACKGROUND: Carcinoma in situ of the bladder is a high-grade cancer that originates in the superficial layer of the bladder. It has the potential to invade nearby organs, and it can spread through blood and lymphatic circulation to distant parts of the body. CASE PRESENTATION: A 58-year-old non-smoker male presented with gross and microscopic hematuria. His family history included his father's recent bladder cancer. Initial investigations showed hematuria, inflammation, negative urine culture, digital rectal examination revealed an enlarged right lobe of the prostate, and an elevated Prostate-Specific Antigen level. Histopathological examination of samples taken from the bladder mucosa and the prostate confirmed urothelial carcinoma in situ in the bladder and prostate. Further evaluation revealed no other metastasis. The tumor was classified as T4aN0M0. The patient underwent radical cystoprostatectomy and histopathological examination showed that the tumor invading the muscularis propria of the bladder as well as the prostatic glands, but no malignancy was found in prostatic urethra and other areas. The patient was discharged three weeks post-operation and completed on adjuvant chemotherapy consisting of Gemcitabine, and Cisplatin to prevent of relapse. The patient is currently in a good healthy. CONCLUSION: The occurrence of bladder cancer metastasizing to the prostate without involving the prostatic urethra is uncommon and requires precise diagnostic techniques for accurate tumor classification. Early management is advised to enhance the prognosis for the patient.

Efficacy of Mid-Urethral Sling and Urethral Dilation for Stress Urinary Incontinence Combined with Urethral Stricture in Women.

OBJECTIVE: To investigate the potential clinical benefits of mid-urethral sling (MUS) and urethral dilatation (UD) operations for the treatment of stress urinary incontinence (SUI) combined with urethral stricture. STUDY DESIGN: Descriptive study. Place and Duration of the Study: Department of Urology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China, from January 2017 to 2022. METHODOLOGY: Patients with Qmax <15ml/s or PVR >50ml, and video urodynamic study (VUDS) capable of confirming the presence and position of urethral stricture were included. The clinical efficacy was evaluated by International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF) questionnaire, maximum flow rate (Qmax), and postvoid residual (PVR) urine. ICIQ-SF, Qmax, and PVR were measured presurgery, on postoperative 2-week, and 1-month postsurgery. RESULTS: There were total 19 patients with an average age of 61.37 ± 11.28 years (range 39-84) with SUI and urethral stricture. ICIQ-SF scores were decreased significantly at one month postoperatively compared with the preoperative [5.0 (0.0, 7.0) vs. 14.0 (13.0, 15.0), p <0.001]. Qmax was increased dramatically compared with the preoperative [21.3 (14.0, 28.4) vs. 13.0 (8.7,18.0), p <0.001], and PVR was decreased remarkably than the preoperative [0.0 (0.0,0.0) vs. 0.0 (0.0,60.0), p = 0.018]. Of 19 patients primarily managed with MUS and UD, two patients experienced recurrence requiring repetitive dilation till sling excision surgery was conducted, and improvement was evident in one patient after repeating UD. CONCLUSION: The overall incidence of SUI combined with urethral stricture in women is low. With a success rate of 89.5%, MUS and UD were effective therapies for the co-existence of SUI with urethral stricture, and repeated UD can be performed safely if necessary in long-term follow-up. KEY WORDS: Stress urinary incontinence, Urethral stricture, Mid-urethral sling, Urethral dilatation.

Optimizing Mouse Urodynamic Techniques for Improved Accuracy.

Accurate measurement of urinary parameters in awake mice is crucial for understanding lower urinary tract (LUT) dysfunction, particularly in conditions like neurogenic bladder post-traumatic spinal cord injury (SCI). However, conducting cystometry recordings in mice presents notable challenges. When mice are in a prone and restricted position during recording sessions, urine tends to be absorbed by the fur and skin, leading to an underestimation of voided volume (VV). The goal of this study was to enhance the accuracy of cystometry and external urethral sphincter electromyography (EUS-EMG) recordings in awake mice. We developed a unique method utilizing cyanoacrylate adhesive to create a waterproof skin barrier around the urethral meatus and abdomen, preventing urine absorption and ensuring precise measurements. Results show that after applying the cyanoacrylate, the sum of VV and RV remained consistent with the infused saline volume, and there were no wet areas observed post-experiment, indicating successful prevention of urine absorption. Additionally, the method simultaneously stabilized the electrodes connected with the external urethral sphincter (EUS), ensured stable electromyography (EMG) signals, and minimized artifacts caused by the movement of the awakened mouse and manipulation of the experimenter. Methodological details, results, and implications are discussed, highlighting the importance of improving urodynamic techniques in preclinical research.

Complete urethral disruption after motor vehicle crash without pelvic fracture.

Urethral injuries are rare among the pediatric population, and the majority occur after trauma. This is the case of an eight-year-old female with complete proximal urethral disruption and ruptured bladder neck without pelvic fracture after a motor vehicle crash. After the accident, her bladder neck was reapproximated and a suprapubic tube was placed. Three months later, she underwent reconstruction for a bladder neck closure and appendicovesicostomy. In managing these patients, focus should first be directed at achieving a safe means of urinary drainage, and next to repair the lower urinary tract to maximize continence and minimize complications.

Application of Urethral Contrast Computed Tomography Three-Dimensional Imaging in the Postoperative Assessment of Prostate Hyperplasia.

This study assesses the morphological effectiveness of benign prostatic hyperplasia (BPH) surgery using multislice spiral computed tomography three-dimensional imaging (CT3D) with urethral contrast. Twenty-five male patients with BPH and bladder outlet obstruction (BOO) who underwent bipolar transurethral resection of the prostate were selected. Preoperative and postoperative CT3D indicators of retrograde and voiding cystourethrography, including bladder neck diameter, length of the posterior urethra, and degree of prostate protrusion into the bladder and upper and lower diameter of the prostate were used to assess bladder neck and posterior urethra morphology and BOO severity. In addition, preoperative and postoperative International Prostate Symptom Scores and maximum urine flow rates were compared. Postoperative CT3D was used to evaluate changes following obstruction relief postsurgery. Preoperative CT3D indicated significant BOO, whereas postoperative imaging showed improved patency but with irregular posterior urethral lumens and varying degrees of residual glandular tissue. Comparative analysis of preoperative and postoperative bladder outlet metrics revealed significant changes (p < .05). Urethral contrast CT3D effectively visualizes the prostate, bladder neck, and prostatic urethra. It quantifies changes in the urethral lumen postsurgery, correlating the extent of posterior urethral lumen spaciousness with urinary flow rates.

Efficacy comparison between Mathieu combined urethral plate incision and onlay island flap urethroplasty for distal hypospadias in patients with urethral plate stenosis.

The aim of the study was to compare the efficacy of Mathieu combined urethral plate incision (Mathieu-IP) versus onlay island flap urethroplasty in patients with distal hypospadias complicated by urethral stenosis. The clinical data of 70 patients with distal hypospadias complicated by urethral plate stenosis treated in the Department of Urology, Anhui Provincial Children's Hospital (Hefei, China), from May 2019 to May 2022, were retrospectively analyzed. Thirty-eight patients underwent Mathieu-IP (Mathieu-IP group) and 32 underwent onlay island flap urethroplasty (Onlay group). Follow-ups at 1 month, 6 months, and 12 months postoperatively assessed operative time, complications, urethral meatus morphology, and family satisfaction. The Mathieu-IP group had significantly shorter operative time (mean ± standard deviation [s.d.]: 81.58 ± 5.18 min) versus the Onlay group (mean ± s.d.: 110.75 ± 6.05 min; P < 0.05). Surgical success rates were 78.9% (Mathieu-IP group) and 75.0% (Onlay group), with no significant difference ( P > 0.05). Complications were comparable between the groups. The Mathieu-IP group resulted in a vertical slit-shaped urethral meatus in 89.5% versus 13.8% in the Onlay group ( P < 0.05). Family satisfaction with general penile appearance and skin shape showed no significant differences, but the Mathieu-IP group had higher satisfaction with meatal position ( P < 0.05). Mathieu-IP offers simplicity, safety, and shorter operative time compared to Onlay. Both the techniques effectively treat urethral plate stenosis in distal hypospadias, with reduced postoperative complications compared to tubularized incised plate urethroplasty. Mathieu-IP results in a vertical slit-shaped urethral meatus which enhances urinary stream, indicating its potential for broader adoption.

IRIS U kit usefulness in transanal total mesorectal excision for lower rectal cancer to avoid urethral injury.

Transanal total mesorectal excision (taTME) has improved the laparoscopic dissection for rectal cancer in the narrow pelvis. Although taTME has more clinical benefits than laparoscopic surgery, such as a better view of the distal rectum and direct determination of distal resection margin, an intraoperative urethral injury could occur in excision ta-TME. This study aimed to determine the feasibility and efficacy of the ta-TME with IRIS U kit surgery. This retrospective study enrolled 10 rectal cancer patients who underwent a taTME with an IRIS U kit. The study endpoints were the safety of access (intra- or postoperative morbidity). The detectability of the IRIS U kit catheter was investigated by using a laparoscope-ICG fluorescence camera system. Their mean age was 71.4±6.4 (58-78) years; 80 were men, and 2 were women. The mean operative time was 534.6 ± 94.5 min. The coloanal anastomosis was performed in 80%, and 20% underwent abdominal peritoneal resection. Two patients encountered postoperative complications graded as Clavien-Dindo grade 2. The transanal approach with IRIS U kit assistance is feasible, safe for patients with lower rectal cancer, and may prevent intraoperative urethral injury.

Differences in bladder neck angles between female patients with overactive bladders and healthy peers.

AIM: The aim of this study was to compare the differences between angles of bladder neck in girls with overactive bladder and those in healthy ones using transabdominal ultrasonography. MATERIALS AND METHODS: This study consists of 28 girls complicated with overactive bladder (Group I) and 40 healthy girls (Group II). The anteroposterior vesical wall angle (APVA), urethroposterior vesical wall angle (UPVA), urethroanterior vesical wall angle (UAVA), thickness of bladder mucosa, distance of urethral orifices, and distance between ureter and urethra orifice were measured in supine position using transabdominal ultrasonography. The results were compared between the two groups. RESULTS: UAVA in Group I was higher than Group II (135.2 ± 12.2 mm vs. 117.4 ± 14.0 mm; p = 0.009). UPVA was smaller in Group I than Group II (114.6 ± 19.5 mm vs. 135.3 ± 16.5 mm; p = 0.014). The distance between the ureteral orifices was 31.8 ± 8.5 mm in Group I and 17.0 ± 4.1 mm in Group II (p < 0.001). There was no statistically significant difference between groups in terms of APVA, bladder mucosa thickness, and distance between ureter and urethra orifice (p > 0.05). CONCLUSION: Bladder neck dynamics may play an important role in overactive bladder pathophysiology due to differences in UPVA, UAV, and location of ureteral orifices in this patient population.

Distribution of prostatic markers in glands of the female urethra and anterior vaginal wall-a rapid autopsy study.

BACKGROUND: There are varying reports of immunohistochemically detected prostatic marker protein distribution in glands associated with the female urethra that may be related to tissue integrity at the time of fixation. AIM: In this study we used tissue derived from rapid autopsies of female patients to determine the distribution of glandular structures expressing prostate-specific antigen (PSA) and prostate-specific acid phosphatase (PSAP) along the female urethra and in surrounding tissues, including the anterior vaginal wall (AVW). METHODS: Tissue blocks from 7 donors that contained the entire urethra and adjacent AVW were analyzed. These tissue samples were fixed within 4-12 hours of death and divided into 5-mm transverse slices that were paraffin embedded. Sections cut from each slice were immunolabeled for PSA or PSAP and a neighboring section was stained with hematoxylin and eosin. The sections were reviewed by light microscopy and analyzed using QuPath software. OBSERVATIONS: In tissue from all donors, glandular structures expressing PSA and/or PSAP were located within the wall of the urethra and were present along its whole length. RESULTS: In the proximal half of the urethra from all donors, small glands expressing PSAP, but not PSA, were observed adjacent to the and emptying into the lumen. In the distal half of the urethra from 5 of the 7 donors, tubuloacinar structures lined by a glandular epithelium expressed both PSA and PSAP. In addition, columnar cells at the surface of structures with a multilayered transitional epithelium in the distal half of the urethra from all donors expressed PSAP. No glands expressing PSA or PSAP were found in tissues surrounding the urethra, including the AVW. CLINICAL IMPLICATIONS: Greater understanding of the distribution of urethral glands expressing prostatic proteins in female patients is important because these glands are reported to contribute to the female sexual response and to urethral pathology, including urethral cysts, diverticula, and adenocarcinoma. STRENGTHS AND LIMITATIONS: Strengths of the present study include the use of rapid autopsy to minimize protein degradation and autolysis, and the preparation of large tissue sections to demonstrate precise anatomical relations within all the tissues surrounding the urethral lumen. Limitations include the sample size and that all donors had advanced malignancy and had undergone previous therapy which may have had unknown tissue effects. CONCLUSION: Proximal and distal glands expressing prostate-specific proteins were observed in tissue from all donors, and these glands were located only within the wall of the urethra.

Pelvic fracture urethral injury in adolescents - Predictors of outcomes and surgical complexity.

INTRODUCTION: Pelvic fracture urethral injury (PFUI) is more severe in younger individuals. The adolescent group is prone to protracted morbidity due to severity of the injury and its impact on lifestyle. Hence, treatment options and data on outcomes are crucial in planning management. The adolescents are a subgroup in several series of PFUI, but literature exclusively studying this group is sparse. MATERIALS & METHODS: A retrospective review of all adolescents (aged between 10 and 19 years as defined by WHO) who underwent surgical repair for PFUI between January 2005 and December 2019 was conducted. Success was defined as a bell-shaped urine flow curve and Qmax of >15 ml/s, no evidence of re-stricture (on cystoscopy/MCU), and no re-intervention. Measurements of the length of the urethral defect and bulbar urethra were done using a digital scale by the radiologist from micturating cystourethrogram (MCU). The Gapometry/Urethrometry (GU) index was calculated as the ratio of the length of the urethral defect to that of the bulbar urethra. Data was analysed using SPSS software version 20.0 and Stata Version 16. The primary outcome was the success of anastomotic urethroplasty. Secondary outcomes were evaluating factors predicting operative complexity (simple perineal versus elaborate perineal approach). RESULTS: We studied 22 patients, out of which 8 were referred following prior failed intervention elsewhere. The mean age was 16.5 + 2.7 years. All the patients were treated using a perineal approach with an overall success rate of 90.9%. Two patients had a failure and were managed with Endoscopic Internal Urethrotomy (EIU), and urethral dilatation. The median follow-up was 24 months. All 8 patients with prior failed interventions had a successful outcome. Twelve patients required inferior pubectomy (elaborate perineal approach). The median length of the urethral defect (2.3 cm IQR- 1.45,3.30 vs. 1 cm, IQR-0.65, 1.6) and the mean GU index (0.45 ± 0.18 cm vs. 0.25 cm ± 0.12 cm) were significantly higher in those who required an elaborate perineal approach. CONCLUSIONS: The perineal approach for surgical repair (anastomotic urethroplasty) of pelvic fracture urethral injury has a favourable success rate of 90.9% in adolescents. Re-do anastomotic urethroplasty for prior failed repairs also had a high success rate of 100%. Cases requiring an elaborate perineal approach were associated with a significantly higher Gapometry/Urethrometry Index (>0.45) and length of the urethral defect (>2.3 cm). This information may assist in patient counselling and preparation for additional steps during repair.

Comparative analysis of recurrence rates between intravesical gemcitabine and bacillus Calmette-Guérin induction therapy following transurethral resection of bladder tumors in patients with intermediate- and high-risk bladder cancer: A retrospective multicenter study.

PURPOSE: This study investigated the efficacy of intravesical gemcitabine as an alternative to bacillus Calmette-Guérin (BCG) therapy. MATERIALS AND METHODS: Data were retrospectively collected across seven institutions from February 1999 to May 2023. Inclusion criteria included patients with intermediate- or high-risk non-muscle invasive bladder cancer (NMIBC) who underwent transurethral resection of bladder tumors (TURBT) and received at least four sessions of intravesical gemcitabine or BCG induction therapy. Patient characteristics, complete remission (CR), occurrence, and progression rates were compared. RESULTS: In total, 149 patients were included in this study (gemcitabine, 63; BCG, 86). No differences were apparent between the two groups in baseline characteristics, except for the follow-up period (gemcitabine, 9.2±5.9 months vs. BCG, 43.9±41.4 months, p<0.001). There were no consistent significant differences observed between the two groups in the 3-month (gemcitabine, 98.4% vs. BCG, 95.3%; p=0.848), 6-month (94.9% vs. 90.0%, respectively; p=0.793) and 1-year CR rates (84.2% vs. 83.3%, respectively; p=0.950). Also, there was no significant statistical difference in progression-free survival between the two groups (p=0.953). The occurrence rates of adverse events were similar between the groups (22.2% vs. 22.1%; p=0.989); however, the rate of Clavien-Dindo grade 2 or higher was significantly higher in the BCG group (1.6% vs. 16.3%, respectively; p<0.001). CONCLUSIONS: Intravesical gemcitabine demonstrated efficacy comparable to BCG therapy for the first year in patients with intermediate- and high-risk NMIBC. However, long-term follow-up studies are warranted.

Time-dependent progress of lower urinary tract dysfunction in streptozotocin-induced diabetic rats with or without low-dose insulin treatment.

Objectives: To examine time-dependent functional and structural changes of the lower urinary tract in streptozotocin-induced diabetic rats with or without low-dose insulin treatment and explore the pathophysiological characteristics of insulin therapy on lower urinary tract dysfunction (LUTD) caused by diabetes mellitus (DM). Methods: Female Sprague-Dawley rats were divided into five groups: normal control (NC) group, 4 weeks insulin-treated DM (4-DI) group, 4 weeks DM (4-DM) group, 8 weeks insulin-treated DM (8-DI) group and 8 weeks DM (8-DM) group. DM was initially induced by i.p. injection of streptozotocin (65 mg/kg), and then the DI groups received subcutaneous implantation of insulin pellets under the mid dorsal skin. Voiding behavior was evaluated in metabolic cages. The function of bladder and urethra in vivo were evaluated by simultaneous recordings of the cystometrogram and urethral perfusion pressure (UPP) under urethane anesthesia. The function of bladder and urethra in vitro were tested by organ bath techniques. The morphologic changes of the bladder and urethra were investigated using Hematoxylin-Eosin and Masson's staining. Results: Both 4-and 8-weeks diabetic rats have altered micturition patterns, including increased 12-h urine volume, urinary frequency/12 hours and voided volume. In-vivo urodynamics showed the EUS bursting activity duration is longer in 4-DM group and shorter in 8-DM group compared to NC group. UPP change in 8-DM were significantly lower than NC group. While none of these changes were found between DI and NC groups. Organ bath showed the response to Carbachol and EFS in bladder smooth muscle per tissue weights was decreased significantly in 4- and 8-weeks DM groups compared with insulin-treated DM or NC groups. In contrast, the contraction of urethral muscle and maximum urethral muscle contraction per gram of the tissue to EFS stimulation were significantly increased in 4- and 8-weeks DM groups. The thickness of bladder smooth muscle was time-dependently increased, but the thickness of the urethral muscle had no difference. Conclusions: DM-induced LUTD is characterized by time-dependent functional and structural remodeling in the bladder and urethra, which shows the hypertrophy of the bladder smooth muscle, reduced urethral smooth muscle relaxation and EUS dysfunction. Low-dose insulin can protect against diuresis-induced bladder over-distention, preserve urethral relaxation and protect EUS bursting activity, which would be helpful to study the slow-onset, time-dependent progress of DM-induced LUTD.