Japanese survey of perioperative complications and ureteral stricture after ureteroscopy with laser lithotripsy for upper urinary tract stones in multicenter collaborative study.

OBJECTIVES: This study aimed to investigate perioperative complications and the details of postoperative ureteral stricture after ureteroscopy with laser lithotripsy (URS-L) for upper urinary tract stones in Japan. METHODS: Patient data on intra- and postoperative complications after ureteroscopy using URS-L were retrospectively collected from multiple centers in Japan between April 2017 and March 2020 with the cooperation of the Japanese Society of Endourology and Robotics. Data included the number of patients undergoing URS-L, number and type of intra- and postoperative complications, and detailed characteristics of postoperative ureteral stricture. RESULTS: In total, 14 125 patients underwent URS-L over 3 years at 82 institutions. Annual URS-L numbers gradually increased from 4419 in 2017, to 4760 in 2018, and 4946 in 2019. The total complication rate was 10.5%, which was divided into intra-operative complications in 1.40% and postoperative complications in 9.18%. The annual incidences of intra- and postoperative complications were not significantly different from year to year (p = 0.314 and p = 0.112). Ureteral perforation, ureteral avulsion, and the intra-operative conversion rate were 1.35%, 0.03%, and 0.02%, respectively. Fever >38°C, septic shock, blood transfusion, and postoperative mortality were 7.44%, 0.81%, 0.07%, and 0.04%, respectively. Ureteral stricture occurred in 0.8% of cases. The median length of stricture site was 10.0 mm and the success rate of stricture treatment was 54.6%. CONCLUSION: Although URS-L utilization has increased in Japan, the annual complication rate has remained steady. Although URS-L is a useful and less invasive procedure, devastating complications can still occur.

Ureteral Strictures Following Ureteroscopy for Kidney Stone Disease: A Population-based Assessment.

PURPOSE: As the prevalence of urolithiasis increases and ureteroscopy is used more frequently, the risks of uncommon complications such as ureteral stricture may become more notable. Our objective is to assess the rate and associated risk factors of ureteral stricture formation in patients undergoing ureteroscopy. MATERIALS AND METHODS: Utilizing the IBM MarketScan research database, we evaluated data from 2008 to 2019 and compared ureteral stricture rates and their management following ureteroscopy to subjects who had shock wave lithotripsy. Shock wave lithotripsy was used as a comparison group to represent the rate of stricture from stone disease alone. A third group of those having both shock wave lithotripsy and ureteroscopy was included. Patients and secondary procedures were identified using Current Procedural Terminology, and International Classification of Diseases-9 and -10 codes. RESULTS: A total of 329,776 patients received ureteroscopy, shock wave lithotripsy, or shock wave lithotripsy+ureteroscopy between 2008 and 2019. Stricture developed in 2.9% of patients after ureteroscopy, 1.5% after shock wave lithotripsy, and 2.6% after shock wave lithotripsy+ureteroscopy. In the multivariable model, rates of stricture were 1.7-fold higher after ureteroscopy vs shock wave lithotripsy (OR:1.71, 95% CI 1.62-1.81). Preoperative hydronephrosis, age, prior stones/intervention, and concurrent kidney and ureteral stones were associated with increased risk of stricture. Of those with strictures incurred after ureteroscopy, 35% required drainage, 21% had endoscopic intervention, 4.8% required reconstructive surgery, and 1.7% underwent nephrectomy. CONCLUSIONS: Ureteral stricture rate after ureteroscopy of nearly 3% was higher than expected and approximately twice the rate attributable to stone disease alone. Factors associated with the stone as well as instrumentation were found to be risk factors. The morbidity of stricture disease following ureteroscopy was significant.

Can preoperative ureteral stents reduce the incidence of ureteral stricture after radiotherapy in patients with cervical cancer?

OBJECTIVE: To determine the impact of preoperative stent placement on postradiotherapy stricture rate in patients with cervical cancer after radical resection. METHODS: This study was a retrospective analysis of data collected from 55 cervical cancer patients treated with radiotherapy between June 2016 and June 2020. Patients were divided into the stent and control groups. After 3 months, the stricture rate and the complications related to stent placement between the two groups were compared. RESULTS: There were 12 (46.2%) and 10 (34.5%) cases of ureteral stricture in the stent (n = 26) and control (n = 29) groups, respectively, three months after the end of radiotherapy. The incidence rates of ureter stricture in the two groups were not significantly different (P = 0.378). Moreover, there were 20 units (38.5%) and 15 units (25.9%) ureteral strictures in the stent and control groups, respectively. No significant difference in the incidence rates of ureteral strictures was found between the two groups (P = 0.157). There were 13 (50.0%) and 10 (34.5%) cases of ureteral stricture in the stent (n = 26) and control (n = 29) groups, respectively, six months after the end of the radiotherapy. The incidence rates of ureter stricture in the two groups were not significantly different (P = 0.244). Moreover, there were 21 units (40.4%) and 15 units (25.9%) ureteral strictures in the stent and control groups, respectively. No significant difference in the incidence rates of ureteral strictures was found between the two groups (P = 0.105). Complications related to stent placement such as urinary tract infections and bladder irritation were statistically significant (P = 0.006 and P = 0.036) between the two groups; while the other complications were not significantly different (P = 0.070, P = 0.092 and P = 0.586). CONCLUSIONS: Ureteral stents may not reduce the incidence of ureteral stricture after radiotherapy in patients with cervical cancer. The stent needs to be replaced regularly, and the complications related to stent placement may occur at any time. Thus, preoperative stent placement should be cautious for the clinical management of cervical cancer patients treated with postoperative radiotherapy.

Evaluation of Ureteroenteric Anastomotic Strictures after the Introduction of Robot-Assisted Radical Cystectomy with Intracorporeal Urinary Diversion: Results from a Large Tertiary Referral Center.

PURPOSE: Benign ureteroenteric anastomotic strictures following radical cystectomy are a critical complication. The incidence is highly dependent on study design, surgical technique and surgeon experience. We studied the incidence of ureteroenteric anastomotic strictures after open vs robot-assisted radical cystectomy with an intracorporeal urinary diversion, and determined the influence of the introduction of robot-assisted radical cystectomy in our clinic. MATERIALS AND METHODS: A retrospective, single center, cohort study was performed between January 2012 and December 2017 in all patients undergoing radical cystectomy. Multivariate analysis was performed to determine which patient or disease-specific factors were associated with development of ureteroenteric anastomotic strictures. RESULTS: Of 279 patients, 192 (69%) underwent open radical cystectomy and 87 (31%) underwent robot-assisted radical cystectomy with intracorporeal urinary diversion. In total, 47/279 patients (17%) developed ureteroenteric anastomotic strictures after a median of 3.0 months (95% CI 2.4-3.7). The difference in incidence of ureteroenteric anastomotic strictures was statistically significant between open and robot-assisted radical cystectomy (13% vs 25%, p <0.001). On multivariate analysis, only surgical technique (open vs robot-assisted radical cystectomy) was independently associated with development of ureteroenteric anastomotic strictures (p=0.004). There was a peak incidence of ureteroenteric anastomotic strictures after robot-assisted radical cystectomy of 47% during the first year after introduction of the robot-assisted procedure. CONCLUSIONS: Introducing robot-assisted radical cystectomy with intracorporeal urinary diversion can result in an initial peak incidence of strictures, highlighting the importance of surgeon experience and the presence of a learning curve. Nonetheless, after experience has been gained, our results show that patients undergoing robot-assisted radical cystectomy with intracorporeal urinary diversion are still more likely to develop ureteroenteric anastomotic strictures compared to those undergoing open radical cystectomy.

Renal outcomes in adult patients with horseshoe kidney.

BACKGROUND: Horseshoe kidney (HSK) is a congenital disorder that is usually asymptomatic, but that increases the risks of kidney stones and infectious disease. However, renal outcomes such as end-stage renal disease (ESRD) in patients with HSK remain unclear. METHODS: In total, 146 patients with HSK (age of ≥20 years) from two tertiary hospitals were included in this study. Control individuals who underwent medical check-ups were selected by matching for age, sex, serum creatinine level, hypertension and diabetes. The hazard ratios (HRs) for the risks of ESRD and all-cause mortality were calculated after adjustment for multiple variables. RESULTS: The proportions of HSK-related complications for obstruction, kidney stones, urinary tract infection and urogenital cancer were 26, 25, 19 and 4%, respectively. During the median follow-up period of 9 years (maximum 32 years), the incidence of ESRD was 2.6/10 000 person-years. The risk of ESRD in patients with HSK was higher than in control individuals [adjusted HR = 7.6; 95% confidence interval (CI) 1.14-50.47]. All-cause mortality did not differ between the two groups (adjusted HR = 0.6; 95% CI 0.08-4.29). CONCLUSIONS: Patients with HSK are at risk of ESRD, which may be attributable to the high prevalence of complications. Accordingly, these patients should be regarded as having chronic kidney disease and require regular monitoring of both kidney function and potential complications.

Risk factors for ureteral obstruction and the diagnostic value of the "cysto-under-tension" technique at the time of uterosacral colpopexy.

INTRODUCTION AND HYPOTHESIS: The objective is to determine the incidence of ureteral obstruction and delayed ureteral injury and to identify risk factors for ureteral obstruction following uterosacral colpopexy. The secondary objective is to evaluate the diagnostic value of the "cysto-under-tension" technique, when a cystoscopy is performed prior to vaginal cuff closure with the uterosacral sutures on tension. METHODS: This was a retrospective review of patients undergoing uterosacral ligament colpopexy between 2007 and 2012 with a nested case-control analysis. Patients with documented ureteral obstruction on cystoscopy or a delayed ureteral injury were identified. Cases were defined as patients with a ureteral obstruction on cystoscopy and controls as those who did not; a multivariable regression analysis was performed. RESULTS: A total of 551 patients underwent uterosacral ligament colpopexy. Twenty-four (4.3% [95% CI = 2.94-6.40]) patients had a ureteral obstruction on cystoscopy, and two (0.4% [95% CI = 0.09-1.31]) patients experienced a delayed ureteral injury. The "cysto-under-tension" technique was used in 40 (7.3%) cases, with a sensitivity of 50.0% (CI = 1.26-98.74) and specificity of 97.4% (CI = 86.2-99.9) to detect ureteral obstruction. On logistic regression for the case-control analysis, increased age remained associated with increased odds of ureteral obstruction (adjOR 1.06, 95% CI = 1.02-1.11) and a higher BMI had lower odds (adjOR 0.89, 95% CI = 0.79-0.98). CONCLUSIONS: In this large cohort study, older age was associated with higher odds of obstruction at the time of colpopexy while a higher BMI might have been protective. The "cysto-under-tension" technique overall may not be that useful in detecting ureteral obstructions but has high negative predictive value.

Impact of radiation on the incidence and management of ureteroenteric strictures: a contemporary single center analysis.

BACKGROUND: Ureteroenteric stricture incidence has been reported as high as 20% after urinary diversion. Many patients have undergone prior radiotherapy for prostate, urothelial, colorectal, or gynecologic malignancy. We sought to evaluate the differences between ureteroenteric stricture occurrence between patients who had radiation prior to urinary diversion and those who did not. METHODS: An IRB-approved cystectomy database was utilized to identify ureteroenteric strictures among 215 patients who underwent urinary diversion at a single academic center between 2016 and 2020. Chart abstraction was conducted to determine the presence of confirmed stricture in these patients, defined as endoscopic diagnosis or definitive imaging findings. Strictures due to malignant ureteral recurrence were excluded (3 patients). Statistical analysis was performed using chi squared test, t-test, and Wilcoxon Rank-Sum Test, logistic regression, and Kaplan-Meier analysis of stricture by cancer type. RESULTS: 65 patients had radiation prior to urinary diversion; 150 patients did not have a history of radiation therapy. Benign ureteroenteric stricture rate was 5.3% (8/150) in the non-radiated cohort and 23% (15/65) in the radiated cohort (p = < 0.001). Initial management of stricture was percutaneous nephrostomy (PCN) in 78% (18/23) and the remaining 22% (5/23) were managed with primary retrograde ureteral stent placement. Long term management included ureteral reimplantation in 30.4% (7/23). CONCLUSIONS: Our study demonstrates a significant increase in rate of ureteroenteric strictures in radiated patients as compared to non-radiated patients. The insult of radiation on the ureteral microvascular supply is likely implicated in the cause of these strictures. Further study is needed to optimize surgical approach such as utilization of fluorescence angiography for open and robotic approaches.

Delayed recognition of lower urinary tract injuries following hysterectomy for benign indications: A NSQIP-based study.

OBJECTIVE: To describe the incidence of and factors associated with lower urinary tract complications recognized in the immediate postoperative period following hysterectomy for benign gynecologic indications using the NSQIP (National Surgical Quality Improvement Program) database. METHODS: Patients who underwent hysterectomy for benign indications from 2014 through 2016 were identified in the NSQIP database using Current Procedural Terminology codes and International Classification of Diseases codes. Patient demographics, preoperative comorbidities, ASA classification system scores, and total operating time were collected. Data on 30-day postoperative complication rates, including rates of reoperation and readmission, were also captured. Genitourinary complications were defined as ureteral obstruction, ureteral fistula, and bladder fistula. RESULTS: A total of 45,139 patients met inclusion criteria during the study period. Mean age and body mass index were 31 ± 11years and 32 ± 8 kg/m2. The majority of patients were white (66%), had an ASA class of 2 (67%), and had no major medical comorbidities (68%). The most commonly performed primary surgery was laparoscopic hysterectomy (43%), followed by abdominal hysterectomy (27%). The incidence of any lower urinary tract complication was 0.2% (95% confidence interval, 0.19-0.28): 55 ureteral obstructions (0.1%, 95% confidence interval, 0.09-0.16), 33 ureteral fistulae (0.07%, 95% confidence interval, 0.05-0.1), and 28 bladder fistulae (0.06%, 95% confidence interval, 0.04-0.09). In a multivariable logistic regression model, black race (adjusted odds ratio, 1.90; 95% confidence interval, 1.20-2.96), endometriosis (adjusted odds ratio, 2.29; 95% confidence interval, 1.44-3.52), and prior abdominal surgery (adjusted odds ratio, 1.53; 95% confidence interval, 1.01-2.28) remained significantly associated with the occurrence of any lower urinary tract complication recognized in the immediate 30-day postoperative window. CONCLUSION: Lower urinary tract complications recognized in the immediate postoperative period following hysterectomy for benign gynecologic disease are rare, with ureteral obstruction being the most commonly reported complication. The risk of these complications may be higher in patients who identify as black, had prior abdominal surgery, and/or have a diagnosis of endometriosis.

Is it safe to use a ureteral access sheath in an unstented ureter?

BACKGROUND: The aim of this study was to examine ureteral stricture rate after the use of UAS in an unstented ureter and compare complications of smaller vs. larger-caliber UAS. METHODS: We conducted a retrospective analysis of consecutive RIRS for renal stones, with the use of UAS in unstented ureters. We excluded cases with previous ureteroscopies, who carried ureteral stent or nephrostomy, had impacted stones, underwent radiation treatment, or had urinary tract malignancies. The primary outcome was formation of ureteral strictures diagnosed by hydronephrosis in ultrasound test and late secretion in dynamic renal scan. Secondary outcome was stone-free-rate (SFR) and complications. In addition, we compared safety and efficacy of smaller (9.5/11.5Fr) vs. larger-caliber (12/14Fr) UAS. RESULTS: The cohort included 165 patients with a median follow-up time of 115 days. There was no case of ureteral stricture formation after the use us UAS, despite using a larger-caliber UAS in nearly half the cases. Larger-caliber UAS was not associated with more complications compared to the smaller-caliber one (p = 0.780). SFR was non-significantly higher in the larger-caliber UAS group (p = 0.056), despite having a larger stone burden, and only stone number was associated with SFR (p = 0.003). CONCLUSIONS: These data suggest that the use of UAS during RIRS in an unstented ureter is safe and does not involve ureteral stricture formation after one procedure. Furthermore, the use of wider sheaths was not found to be associated with higher complications rate.

Gastrointestinal cancer and bilateral hydronephrosis resulted in a high risk of ureteral stent failure.

BACKGROUND: Urologists frequently encounter malignant ureteral obstruction (MUO) caused by advanced urological or non-urological malignant disease, but the treatment policy is unclear. The present study examined the risk factors for predicting ureteral stent failure in patients with MUO after ureteral stent insertion and the change in the renal function after retrograde ureteral stent insertion in cases of bilateral hydronephrosis. METHODS: A total of 39 patients who required ureteral stent placement for MUO at Yokohama City University Medical Center (Yokohama, Japan) between February 2007 and May 2016 were included in this study. The age, gender, type of cancer, hydronephrosis side, pre-stenting estimated glomerular filtration rate (eGFR), and eGFR increase were assessed as predictive factors for stent failure. Among these 39 patients, 25 showed bilateral hydronephrosis. Thirteen of these patients had bilateral ureteral stents placed, and the remaining 12 had a unilateral ureteral stent placed. The renal function and overall survival (OS) were analyzed between these two groups. RESULTS: Among all 39 patients, 9 (23.1%) had stent failure. A univariate analysis revealed that causative disease (gastrointestinal cancer vs. others; p = 0.045) and laterality of hydronephrosis (bilateral vs. unilateral; p = 0.05) were associated with stent failure. A multivariate analysis revealed that only age (hazard ratio, 0.938; 95% confidence interval, 0.883-0.996; p = 0.038) was associated with stent failure. A Kaplan-Meier analysis and log-rank test indicated that having a unilateral ureteral stent placed was not correlated with a lower OS rate than having bilateral ureteral stents placed (p = 0.563). Among patients with bilateral hydronephrosis, the increase in the eGFR of those who had bilateral ureteral stents placed was not significantly different from that of those who had a unilateral ureteral stent placed (p = 0.152). CONCLUSIONS: We revealed that age > 60 years was helpful for predicting stent failure. MUO due to gastrointestinal cancer and bilateral hydronephrosis may be predictive of stent failure. These factors may help urologists decide the optimal time to perform early percutaneous nephrostomy. These findings suggest that patients with bilateral hydronephrosis do not necessarily need to have a ureteral stent placed into both sides of the hydronephrosis.

Long-term Risk of Urinary Adverse Events in Curatively Treated Patients With Rectal Cancer: A Population-Based Analysis.

BACKGROUND: Treatment modalities for rectal cancer, including radiation, are associated with urinary adverse effects. OBJECTIVE: The purpose of this study was to determine the influence of surgery and radiation therapy for rectal cancer on long-term urinary complications. DESIGN: Using the Surveillance Epidemiology and End Results-Medicare data set from the United States, patients with rectal cancer older than 66 years of age who underwent rectal resection between 1992 and 2007 were stratified into treatment groups that accounted for surgical resection and the timing of radiation therapy, if used. A control group of patients who did not have rectal cancer were matched by age, sex, demographics, and comorbidities. The primary outcome was a urinary adverse event defined as a relevant urinary diagnosis with an associated procedure. Patients with rectal cancer in different treatment groups were compared with control patients using a propensity-adjusted, multivariable Cox regression analysis. SETTINGS: The study was conducted with the Surveillance Epidemiology and End Results-Medicare data set from the United States at our institution. RESULTS: Of the 11,068 patients with rectal cancer, 56.2% had surgical resection alone, 21.7% received preoperative radiation, and 22.1% received postoperative radiation. The median follow-up for all of the groups of patients was >2 years. All of the groups of patients with rectal cancer were more likely to develop a urinary adverse event compared with control subjects. Adjusted HRs were 2.28 (95% CI, 2.02-2.57) for abdominoperineal resection alone, 2.24 (95% CI, 1.79-2.80) for preoperative radiation and surgical resection, 2.04 (95% CI, 1.70-2.44) for surgical resection and postoperative radiation, and 1.69 (95% CI, 1.52-1.89) for low anterior resection alone. LIMITATIONS: Treatment patterns are somewhat outdated, with a large proportion of patients receiving postoperative radiation. The data did not allow for accurate assessment of urinary tract infections or mild urinary retention that is not managed with a procedure. CONCLUSIONS: Rectal cancer surgery with or without radiation is associated with a higher risk of urinary complications requiring procedures. Patients who undergo low anterior resection without radiation tend toward the lowest risk for a urinary adverse event.

Atrophic bladder in long-term dialysis patients increases the risk for urological complications after kidney transplantation.

OBJECTIVES: To evaluate the risk for urological complications after kidney transplantation at a single medical center in Japan. METHODS: In the present study, 408 kidney recipients (255 men, 153 women) were enrolled. There were 349 living and 59 deceased donors. The average age of the recipients was 42.5 ± 13.5 years, and the average pretransplant dialysis period was 71.8 ± 88.2 months. Ureteroneocystostomy was carried out on 347 patients, and ureteroureterostomy on 61 patients. We investigated the relationship between pretransplant duration of dialysis and bladder capacity, and examined the risk factors for urological complication. We also evaluated the incidence of vesicoureteral reflux in 191 recipients who underwent ureteroneocystostomy during transplantation. RESULTS: The preoperative duration of dialysis therapy showed a significant negative correlation with bladder capacity (R2  = 0.33, P < 0.001). The overall urological complication rate was 3.4% (14 patients), including urinary leakage (12 patients) and ureteral stricture (two patients). Univariate analysis showed that atrophic bladder, long-term dialysis therapy, deceased donor and ureteroureterostomy were associated with a higher incidence of urological complications (odds ratio 8.05, 4.43, 3.42 and 3.35; P < 0.01, P = 0.01, P = 0.04 and P = 0.04, respectively). Furthermore, multivariate analysis showed that atrophic bladder was the only significant factor associated with urological complications (odds ratio 10.37; P = 0.01). Among 191 recipients, vesicoureteral reflux was observed in 32 (16.8%). The incidence of vesicoureteral reflux was significantly higher in patients with atrophic bladder. CONCLUSIONS: Bladder atrophy in renal transplant recipients after long-term dialysis therapy is associated with a higher risk of urological complications.

Ureteroenteric anastomotic revision as initial management of stricture after urinary diversion.

OBJECTIVE: To report our experience with ureteroenteric anastomotic revision as initial treatment of stricture after urinary diversion. METHODS: An institutional review board-approved retrospective study was carried out. A total of 41 patients who underwent primary ureteroenteric anastamotic revision were identified between 2007 and 2015. Data analyzed included patient characteristics, type of diversion, estimated blood loss, operative time, change in renal function, length of stay, postoperative complications and time with nephrostomy/stent. Success of revision was defined as an improvement in hydronephrosis on radiographic imaging and/or reflux during pouchogram. Predictors of length of stay and complications were analyzed using analysis of covariance. RESULTS: A total of 50 renal units were revised with a success rate of 100%. The median length of stay was 6 days (2-16 days). There were a total of 15 complications (one major, 14 minor) in 14 patients (33% 30-day complication rate). The most common were wound infection (n = 4) and arrhythmia (n = 4). Robotic revision (n = 5) had a median length of stay of 3 days (2-4) with no complications. CONCLUSIONS: Primary ureteroenteric anastomotic revisions have an excellent success rate at an experienced center and might obviate the need for multiple interventions. Open revision is associated with mostly minor complications. Robotic revision might reduce the morbidity of open revision in select cases.

Emergency percutaneous nephrostomy versus emergency percutaneous nephrolithotomy in patients with sepsis associated with large uretero-pelvic junction stone impaction: a randomized controlled trial.

INTRODUCTION: A randomized trial was conducted prospectively to evaluate the efficacy, related complications, and convalescence of emergency percutaneous nephrolithotomy compared to percutaneous nephrostomy for decompression of the collecting system in cases of sepsis associated with large uretero-pelvic junction stone impaction. MATERIALS AND METHODS: The inclusion criteria included a WBC count of 10.000/mm3 or more and/or a temperature of 38°C or higher. Besides, all enrolled patients should maintain stable hemodynamic status and proper organ perfusions. A total of 113 patients with large, obstructive uretero-pelvic junction stones and clinical signs of sepsis completed the study protocol. Of those, 56 patients were placed in the emergency percutaneous nephrostomy group, while the other 57 patients were part of the percutaneous nephrolithotomy group. The primary end point was the time until normalization of white blood cells (WBC) at a count of 10.000/mm3 or less, and a temperature of 37.4°C or lower. The secondary end points included the comparison of analgesic consumption, length of stay, and related complications. Statistical analysis was performed using SPSS® version 14.0.1. The Mann-Whitney U test, chi-square test, and Fisher's exact test were used as appropriate. RESULTS: The length of hospital stays (in days) was 10.09±3.43 for the emergency percutaneous nephrostomy group and 8.18±2.72 for the percutaneous nephrolithotomy group. This set of data noted a significant difference between groups. There was no difference between groups in regard to white blood cell count (in mm3), time to normalization of white blood cell count (in days), body temperature (in ºC), time to normalization of body temperature (in days), C-reactive proteins (in mg/dL), time taken for C-reactive proteins to decrease over 25% (in days), procalcitonin (in ng/mL), or complication rates. CONCLUSIONS: This study confirms that emergency percutaneous nephrolithotomy may be as safe as early percutaneous nephrolithotomy in a selected low risk patients with sepsis-associated large, obstructive stone.

High pressure balloon dilatation of the ureterovesical junction in primary obstructive megaureter: Infectious morbidity.

INTRODUCTION: The objective of this study is to investigate the infectious morbidity associated with high-pressure balloon dilatation (HPBD) and an indwelling double J stent, in primary obstructive megaureter. METHODS: We reviewed the cases of 12 patients undergoing endoscopic treatment for primary obstructive megaureter from January 2012 to January 2015. The characteristics of the infection and data concerning the patient and the intervention were analyzed. RESULTS: The frequency of preoperative urinary tract infection (UTI) was 58%. The procedure was feasible in 100% of cases. Two patients required a second dilatation. One patient underwent Cohen's ureteral reimplantation after failure of the second dilatation. The frequency of postoperative UTI was 25%. All these infections occurred in patients with a double J stent. None of the patients had UTI after stent removal. None of the patients developed postoperative vesicoureteral reflux (VUR) after HPBD. CONCLUSION: Endoscopic balloon dilatation has been shown to have good short- mid- and long-term outcomes. In our experience, the morbidity of this procedure mostly results from infections, exclusively related to the use of a double J stent. The placement of a double J stent has a significant medical and economic impact. A definitive decision about the utility of double J stents will require studies of further dilatation without the placement of a double J stent. LEVEL OF EVIDENCE: 4.

Resection of the Intramural Portion of the Distal Ureter during Transurethral Resection of Bladder Tumors: Predictive Factors for Secondary Stenosis and Development of Upper Urinary Tract Recurrence.

PURPOSE: We analyzed the incidence of and predictive factors for ureteral stenosis and recurrent upper urinary tract urothelial carcinoma after resection of tumors located in the intramural portion of the distal ureter. MATERIALS AND METHODS: We retrospectively analyzed the records of 2,317 patients who underwent transurethral resection of bladder tumor for nonmuscle invasive bladder cancer, including 112 (4.83%) with tumors involving the intramural portion of the distal ureter. Multivariate Cox regression analysis was done to determine predictive factors for ureteral stenosis and recurrent urinary tract urothelial carcinoma. RESULTS: At a mean followup of 56 months 17 patients (15.2%) presented with recurrent upper urinary tract urothelial carcinoma and ureteral stenosis had developed in 13 (11.6%). On univariate analysis previous recurrences were associated with both events. On multivariate analysis tumor size 1.5 cm or greater (HR 4.521, p = 0.023) and T1 tumor stage (HR 8.525, p = 0.005) were independent predictive factors for stenosis. Stage T1 in the bladder (HR 7.253, p = 0.001) and carcinoma in situ in the intramural portion of the distal ureter (HR 6.850, p = 0.005) increased the risk of recurrent upper urinary tract urothelial carcinoma. The main study limitation was the lack of information on vesicoureteral reflux due to the retrospective design. CONCLUSIONS: Involvement of the intramural portion of the distal ureter is uncommon. In patients with nonmuscle invasive bladder cancer and involvement of the intramural portion of the distal ureter a stage T1 tumor and a tumor size 1.5 cm or greater are independent predictive factors for distal ureteral stenosis. Moreover, stage T1 and carcinoma in situ in the intramural portion of the distal ureter significantly increase the risk of recurrent upper urinary tract urothelial carcinoma. The urinary tract should be more closely followed in this patient subgroup.

Prevalence and incidence of clinical symptoms of the retroaortic left renal vein.

OBJECTIVE: To analyze the prevalence and incidence of clinical symptoms of retroaortic left renal vein (RLRV) diagnosed incidentally over 10 years by computed tomography (CT). PATIENTS AND METHODS: 7,929 consecutive patients (out- and inpatients) were studied with multidetector CT from January 2000 to April 2011. We retrospectively reviewed RLRV patients' medical records and analyzed their clinical characteristics. RESULTS: A total of 61 out of 7,929 patients had a RLRV, therefore the prevalence was 0.77%. Only 4 of 61 (6.6%) RLRV patients diagnosed by CT scan were clinically symptomatic. RLRV was associated with flank pain and microhematuria in one patient (1.6%), in another one with microhematuria only and in one with ureteropelvic junction obstruction. Furthermore, one patient suffered from arterial hypertension associated with a RLRV. CONCLUSIONS: RLRV is a rare finding, and only a small minority of RLRVs causes symptoms.

MMP-1 and -3 haplotype is associated with congenital anomalies of the kidney and urinary tract.

BACKGROUND: Congenital anomalies of the kidney and urinary tract (CAKUT) are a common cause of progressive chronic kidney disease that may lead to end-stage renal disease and renal replacement therapy in childhood. Altered expression or activity of matrix metalloproteinases (MMPs) have been found in CAKUT. The MMP-1, -3, and -8 polymorphisms studied here are located in the gene promoters and alter expression. Our aim was to investigate associations of MMP polymorphisms, solely and in haplotypes, with CAKUT in children. METHODS: A case-control study with 101 pediatric patients and 281 controls was performed. The MMP-1 (-1607 1G/2G), -3 (5A/6A), and -8 (-799 C/T) genotypes were determined by PCR-restriction fragment length polymorphism. RESULTS: We found statistically significant associations of MMP-3 5A/6A polymorphism (p < 0.0001) and 1G-(1607)-6A haplotype, with no preferences for MMP-8 -799C or T alleles, with CAKUT (OR = 2.93, 95 % CI 1.43-5.98, adjusted for gender, p = 0.003) and with obstructive uropathies in a subgroup of patients (OR = 4.57, 95 % CI 2.74-7.61, adjusted for gender, p < 0.0001). CONCLUSIONS: MMP-3 genotypes and MMP-3 and -1 haplotypes encompassing either MMP-8 -799C or T alleles were associated with CAKUT and obstructive uropathies in pediatric patients. Still, functional and association studies are needed to elucidate evident roles of MMPs in CAKUT.

Bilateral pelvi-ureteric junction obstruction: our experience in a developing country.

BACKGROUND: Bilateral pelvi-ureteric junction (PUJ) obstruction is rare and causes high morbidity and mortality. Recent advances have led to its diagnosis and management in the perinatal period. However, open surgery is still the mainstay of treatment in less endowed nations where late presentation is the norm. MATERIALS AND METHODS: All patients with PUJ obstruction diagnosed and managed at the University of Maiduguri Teaching Hospital between January 2006 and December 2011 were retrospectively reviewed. All had open surgery and all repairs were stented with double J stents or appropriate size feeding tube. RESULTS: A total of 18 patients were analyzed, 11 males and 7 females with a ratio of 1.57:1 and mean age of 27.5 years (age range 2-38). The main clinical features were loin pain (72.22%) and fever (72.22%); while the main complications at presentation were hydronephrosis (55.56%), impaired renal function (61.11%) and pyelonephritis (50%). The causes of obstruction were mainly congenital (50.0%) and due to schistosomal fibrosis/stricture (22.2%). Preliminary double J stents, tube nephrostomies and hemodialysis were used to recover renal function before surgery. Anderson-Hynes (41.7%) and Heineke-Mirhulicz (19.4%) pyeloplasty were the main procedures performed. The main post-operative complications were urinary tract infections (67.67%) and leakage (11.11%). The mean duration of symptoms was 23.72 months and the mean hospital stay was 13 days. The mortality rate was 5.56%. CONCLUSION: Bilateral PUJ obstruction is uncommon in Maiduguri, with congenital causes and schistosomal fibrosis as the most common etiologies. Aggressive treatment aimed at recovering renal function is necessary before open pyeloplasty if morbidity and mortality is to be reduced. Open pyeloplasty remained the best treatment option with favorable outcome.

Five-year experience with metallic stents for chronic ureteral obstruction.

PURPOSE: We present 5 years of outcome data on metallic ureteral stents in a cohort of patients treated for chronic ureteral obstruction. MATERIALS AND METHODS: We retrospectively identified and analyzed the records of all patients in whom a Resonance® Metallic Ureteral Stent was placed between early 2007 and late 2011 at our institution. We performed a descriptive analysis of key outcomes, including the failure and death rates, and stenting duration, defined as the time from initial stent placement to last stent failure or patient death. We also performed a secondary comparative analysis of patients with a benign vs malignant etiology of obstruction. RESULTS: A total of 139 metallic stents were placed in 47 patients, including 27 (57%) with malignant and 20 (43%) with a benign etiology. Of the patients 15 (32%) had bilateral obstruction. Maximum followup was 59 months (mean 20, median 13, IQR 4-31). Stent failure occurred in 13 patients (28%), including 4 in the benign and 9 in the malignant group (p = 0.35). The median duration of stenting for benign and malignant obstruction was 22 (IQR 9-39) vs 7 months (IQR 3-25) (p = 0.106). Stenting duration was equivalent when controlling for the higher death rate in the malignant group. CONCLUSIONS: Resonance metallic stents are an adequate management strategy for benign and malignant ureteral obstruction. A subset of patients in each group continued to do well at more than a 3-year overall duration of stenting. Failure rates were similar for benign and malignant etiologies.