Obstetric outcomes of pregnancy complicated by urolithiasis: a retrospective cohort study.

OBJECTIVES: Evaluate the association between urolithiasis during pregnancy and obstetric outcomes outside the context of urological intervention. METHODS: We conducted a retrospective cohort study of singleton, non-anomalous gestations delivered at 23-42 weeks in California from 2007 to 2011. Maternal outcomes (preterm delivery [early (<32 weeks) and late (<37 weeks)], preeclampsia, gestational diabetes, cesarean deliveries, urinary tract infection [UTI] at delivery, chorioamnionitis, endomyometritis, and maternal sepsis) and newborn outcomes (seizure, respiratory distress syndrome, hypoglycemia, jaundice, and neonatal abstinence syndrome [NAS]) were compared using χ2-tests and multivariable logistic regression. RESULTS: A total of 2,013,767 pregnancies met inclusion criteria, of which 5,734 (0.28%) were complicated by urolithiasis. Stone disease during pregnancy was associated with 30% greater odds of each early (aOR 1.30; 95% CI 1.19-1.43) and late (aOR 1.29; 95% CI 1.18-1.41) preterm delivery. Cesarean delivery, UTI at delivery, gestational hypertension, gestational diabetes, preeclampsia, and sepsis were all significantly positively associated with urolithiasis. Odds of NAS (aOR 2.11; 95% CI 1.27-3.51) and jaundice were significantly greater in the neonates of stone-forming patients (aOR 1.08; 95% CI 1.01-1.16). CONCLUSIONS: Urolithiasis during pregnancy was associated with 30% greater odds of preterm delivery and increased risk of myriad metabolic, hypertensive, and infectious disorders of gestation. Neonates born to stone-forming patients were more than twice as likely to develop neonatal abstinence syndrome but did not have significantly greater odds of complications of prematurity.

Renal Autotransplantation: 27-Year Experience at 2 Institutions.

PURPOSE: Renal autotransplantation is an infrequently performed procedure. It has been used to manage complex ureteral disease, vascular anomalies and chronic kidney pain. We reviewed our 27-year experience with this procedure. MATERIALS AND METHODS: This is a retrospective, observational study of 51 consecutive patients who underwent renal autotransplantation, including 29 at Oregon Health and Science University between 1986 and 2013, and 22 at Virginia Mason Medical Center between 2007 and 2012. Demographics, indications, operative details and followup data were collected. Early (30 days or less) and late (greater than 30 days) complications were graded according to the Clavien-Dindo system. Factors associated with complications and pain recurrence were evaluated using a logistic regression model. RESULTS: The 51 patients underwent a total of 54 renal autotransplants. Median followup was 21.5 months. The most common indications were loin pain hematuria syndrome/chronic kidney pain in 31.5% of cases, ureteral stricture in 20.4% and vascular anomalies in 18.5%. Autotransplantation of a solitary kidney was performed in 5 patients. Laparoscopic nephrectomy was performed in 23.5% of cases. Median operative time was 402 minutes and median length of stay was 6 days. No significant difference was found between preoperative and postoperative plasma creatinine (p = 0.74). Early, high grade complications (grade IIIa or greater) developed in 14.8% of patients and 12.9% experienced late complications of any grade. Two graft losses occurred. Longer cold ischemia time was associated with complications (p = 0.049). Of patients who underwent autotransplantation for chronic kidney pain 35% experienced recurrence and 2 underwent transplant nephrectomy. No predictors of pain recurrence were identified. CONCLUSIONS: The most common indications for renal autotransplantation were loin pain hematuria syndrome/chronic kidney pain, ureteral stricture and vascular anomalies in descending order. Kidney function was preserved postoperatively and 2 graft losses occurred. At a median followup of 13 months pain resolved in 65% of patients who underwent the procedure. Complication rates compared favorably with those of other major urological operations and cold ischemia time was the only predictor of postoperative complications.

Review of appendiceal onlay flap in the management of complex ureteric strictures in six patients.

OBJECTIVES: To evaluate appendiceal onlay flap ureteroplasty for repairing complex right proximal and mid-ureteric strictures. PATIENTS AND METHODS: Between August 2006 and August 2012 four women and two men (mean age 34.2 years) underwent right laparoscopic appendiceal onlay flap ureteroplasty. The mean stricture length was 2.5 cm. Stricture formation was secondary to impacted ureteric stones in three patients and failed pyeloplasty for congenital pelvi-ureteric junction obstruction in the remaining three. Each patient had ipsilateral flank pain before surgery. RESULTS: The mean operating time, estimated blood loss and hospital stay were 244 min, 175 mL and 3.2 days, respectively. No intra- or peri-operative complications were noted. The objective success rate was 100% (all patients had radiographic and/or endoscopic resolution of their ureteric strictures). The subjective success rate was 66%, (two patients developed recurrent discomfort, which upon exploration was found to be attributable to fibrosis away from the appendiceal onlay graft, where the gonadal vessels crossed the ureter). Both patients with recurrent pain underwent laparoscopic ureterolysis and bladder advancement flap proximal to the appendiceal onlay, which markedly improved one patient's pain but the other patient continued to have discomfort, ultimately resulting in a laparoscopic nephroureterectomy. CONCLUSIONS: Appendiceal onlay ureteroplasty is a viable treatment option for patients with complex right proximal and mid-ureteric strictures, while minimising the potential morbidity of appendiceal and ileal interposition.

Heterogeneity in stone culture protocols and endourologist practice patterns: a multi-institutional survey.

Kidney stone cultures can be beneficial in identifying bacteria not detected in urine, yet how stone cultures are performed among endourologists, under what conditions, and by what laboratory methods remain largely unknown. Stone cultures are not addressed by current clinical guidelines. A comprehensive REDCap electronic survey sought responses from directed (n = 20) and listserv elicited (n = 108) endourologists specializing in kidney stone disease. Questions included which clinical scenarios prompt a stone culture order, how results influence post-operative antibiotics, and what microbiology lab protocols exist at each institution with respect to processing and resulting stone cultures. Logistic regression statistical analysis determined what factors were associated with performing stone cultures. Of 128 unique responses, 11% identified as female and the mean years of practicing was 16 (range 1-46). A specific 'stone culture' order was available to only 50% (64/128) of those surveyed, while 32% (41/128) reported culturing stone by placing a urine culture order. The duration of antibiotics given for a positive stone culture varied, with 4-7 days (46%) and 8-14 days (21%) the most reported. More years in practice was associated with fewer stone cultures ordered, while higher annual volume of percutaneous nephrolithotomy was associated with ordering more stone cultures (p < 0.01). Endourologists have differing practice patterns with respect to ordering stone cultures and utilizing the results to guide post-operative antibiotics. With inconsistent microbiology lab stone culture protocols across multiple institutions, more uniform processing is needed for future studies to assess the clinical benefit of stone cultures and direct future guidelines.

Cost-Effectiveness of Urolithiasis Management in Pregnancy.

INTRODUCTION: Urolithiasis complicating pregnancy presents a challenge for urology and obstetric teams. The management options of ureteral stenting, percutaneous nephrostomy and ureteroscopy vary significantly with regard to efficacy, complications, impact on quality of life and costs. This analytic model compares these factors to determine an optimal strategy per gestational age at presentation. METHODS: A decision analytic model was built that compared stenting, percutaneous nephrostomy and ureteroscopy. Outcomes included treatment failure, need for re-treatment and complications stratified by severity. Probabilities and utilities were derived from the literature and costs were derived from institutional charge data. The time horizon was 1 year with disutilities limited to gestation length or recovery time for treatment or complication. Multivariate sensitivity analyses and Monte Carlo analysis were performed to evaluate model robustness. RESULTS: In a simulated cohort of 1,000 pregnant women with urolithiasis ureteroscopy would yield 960 quality adjusted life years, compared to 870 with stenting and 880 with percutaneous nephrostomy. Treatment via stenting or percutaneous nephrostomy would fail more than twice as often as ureteroscopy and more than half of patients would require subsequent definitive management. In this cohort ureteroscopy would save $38.8 million compared to stenting and $17.6 million compared to percutaneous nephrostomy. Given its lower costs and improved outcomes, ureteroscopy was the dominant strategy across all gestational ages and remained dominant in all sensitivity analyses and Monte Carlo simulations. CONCLUSIONS: Regardless of gestational age, ureteroscopy was a cost-effective strategy to manage urolithiasis compared to stenting or percutaneous nephrostomy. This result was robust against substantial changes in model parameters.

Computed Tomography Radiation Exposure Among Referred Kidney Stone Patients: Results from the Registry for Stones of the Kidney and Ureter.

Purpose: Kidney stone patients routinely have CT scans during diagnostic work-up before being referred to a tertiary center. How often these patients exceed the recommended dose limits for occupational radiation exposure of >100 mSv for 5 years and >50 mSv in a single year from CT alone remains unknown. This study aimed to quantify radiation doses from CTs received by stone patients before their evaluation at a tertiary care stone clinic. Methods: From November 2015 to March 2017, consecutive new patients enrolled into the Registry for Stones of the Kidney and Ureter (ReSKU™) had the dose-length product of every available CT abdomen/pelvis within 5 years of their initial visit recorded, allowing for an effective dose (EDose) calculation. Multivariate logistic regression analysis identified factors associated with exceeding recommended dose limits. Models were created to test radiation reducing effects of low-dose and phase-reduction CT protocols. Results: Of 343 noncontrast CTs performed, only 29 (8%) were low-dose CTs (calculated EDose <4 mSv). Among 389 total patients, 101 (26%) and 25 (6%) had an EDose >20 mSv and >50 mSv/year, respectively. Increased body mass index, number of scans, and multiphase scans were associated with exceeding exposure thresholds (p < 0.01). The implementation of a low-dose CT protocol decreased the estimated number of scans contributing to overexposure by >50%. Conclusions: Stone patients referred to a tertiary stone center may receive excessive radiation from CT scans alone. Unnecessary phases and underutilization of low-dose CT protocols continue to take place. Enacting new approaches to CT protocols may spare stone patients from exceeding recommended dose limits.

The Morbidity of Ureteral Strictures in Patients with Prior Ureteroscopic Stone Surgery: Multi-Institutional Outcomes.

PURPOSE: Nephrolithiasis is an increasingly common ailment in the United States. Ureteroscopic management has supplanted shockwave lithotripsy as the most common treatment of upper tract stone disease. Ureteral stricture is a rare but serious complication of stone disease and its management. The impact of new technologies and more widespread ureteroscopic management on stricture rates is unknown. We describe our experience in managing strictures incurred following ureteroscopy for upper tract stone disease. MATERIALS AND METHODS: Records for patients managed at four tertiary care centers between December 2006 and October 2015 with the diagnosis of ureteral stricture following ureteroscopy for upper tract stone disease were retrospectively reviewed. Study outcomes included number and type (endoscopic, reconstructive, or nephrectomy) of procedures required to manage stricture. RESULTS: Thirty-eight patients with 40 ureteral strictures following URS for upper tract stone disease were identified. Thirty-five percent of patients had hydronephrosis or known stone impaction at the time of initial URS, and 20% of cases had known ureteral perforation at the time of initial URS. After stricture diagnosis, the mean number of procedures requiring sedation or general anesthesia performed for stricture management was 3.3 ± 1.8 (range 1-10). Eleven strictures (27.5%) were successfully managed with endoscopic techniques alone, 37.5% underwent reconstruction, 10% had a chronic stent/nephrostomy, and 10 (25%) required nephrectomy. CONCLUSIONS: The surgical morbidity of ureteral strictures incurred following ureteroscopy for stone disease can be severe, with a low success rate of endoscopic management and a high procedural burden that may lead to nephrectomy. Further studies that assess specific technical risk factors for ureteral stricture following URS are needed.

Identifying factors associated with need for flexible ureteroscope repair: a Western Endourology STone (WEST) research consortium prospective cohort study.

Maintenance of flexible ureteroscopes can involve high costs and administrative burden. Instrument fragility necessitates eventual repair, rendering scopes inaccessible during refurbishment. We conducted a multi-institutional prospective cohort study to identify perioperative factors influencing flexible ureteroscope durability. Patients undergoing flexible ureteroscopy (URS) at six United States endourology centers were enrolled between August 2014 and June 2015. Surgeon self-reported concern and satisfaction with scope performance as well as upward and downward angles of deflection for each scope tip were measured before and after each procedure. The need for scope repair was determined by the operating surgeon at the time of the procedure and recorded. 424 URS cases using 74 flexible ureteroscopes were identified. Scope repair was required in 28 cases (6.6%) involving 26 scopes (35.1%). Upon univariate analysis, shorter patient height, absence of guidewire use, presence of a ureteral access sheath (UAS), longer procedure time, larger stone size, lithotrite type, surgeon training level, and self-reported concern were associated with scope repair. Upon multivariate analysis, UAS use (OR = 2.53, p = 0.005) and degree loss of scope upward flexion during a case (OR = 1.02, p = 0.03) increased the odds of a scope needing repair while the use of safety guidewire decreased the odds of a scope repair (OR = 0.50, p = 0.045). Lithotrite use and surgeon concern were associated with degree loss of scope upward flexion. The use of a UAS, absence of a safety guidewire, and the loss of upward ureteroscope flexion should be considered when evaluating means of optimizing reusable ureteroscope durability.

Rationale and Design of the Registry for Stones of the Kidney and Ureter (ReSKU): A Prospective Observational Registry to Study the Natural History of Urolithiasis Patients.

OBJECTIVES: Registry-based clinical research in nephrolithiasis is critical to advancing quality in urinary stone disease management and ultimately reducing stone recurrence. A need exists to develop Health Insurance Portability and Accountability Act (HIPAA)-compliant registries that comprise integrated electronic health record (EHR) data using prospectively defined variables. An EHR-based standardized patient database-the Registry for Stones of the Kidney and Ureter (ReSKU™)-was developed, and herein we describe our implementation outcomes. MATERIALS AND METHODS: Interviews with academic and community endourologists in the United States, Canada, China, and Japan identified demographic, intraoperative, and perioperative variables to populate our registry. Variables were incorporated into a HIPAA-compliant Research Electronic Data Capture database linked to text prompts and registration data within the Epic EHR platform. Specific data collection instruments supporting New patient, Surgery, Postoperative, and Follow-up clinical encounters were created within Epic to facilitate automated data extraction into ReSKU. RESULTS: The number of variables within each instrument includes the following: New patient-60, Surgery-80, Postoperative-64, and Follow-up-64. With manual data entry, the mean times to complete each of the clinic-based instruments were (minutes) as follows: New patient-12.06 ± 2.30, Postoperative-7.18 ± 1.02, and Follow-up-8.10 ± 0.58. These times were significantly reduced with the use of ReSKU structured clinic note templates to the following: New patient-4.09 ± 1.73, Postoperative-1.41 ± 0.41, and Follow-up-0.79 ± 0.38. With automated data extraction from Epic, manual entry is obviated. CONCLUSIONS: ReSKU is a longitudinal prospective nephrolithiasis registry that integrates EHR data, lowering the barriers to performing high quality clinical research and quality outcome assessments in urinary stone disease.

Diagnosis and management of ureteral complications following renal transplantation.

When compared with maintenance dialysis, renal transplantation affords patients with end-stage renal disease better long-term survival and a better quality of life. Approximately 9% of patients will develop a major urologic complication following kidney transplantation. Ureteral complications are most common and include obstruction (intrinsic and extrinsic), urine leak and vesicoureteral reflux. Ureterovesical anastomotic strictures result from technical error or ureteral ischemia. Balloon dilation or endoureterotomy may be considered for short, low-grade strictures, but open reconstruction is associated with higher success rates. Urine leak usually occurs in the early postoperative period. Nearly 60% of patients can be successfully managed with a pelvic drain and urinary decompression (nephrostomy tube, ureteral stent, and indwelling bladder catheter). Proximal, large-volume, or leaks that persist despite urinary diversion, require open repair. Vesicoureteral reflux is common following transplantation. Patients with recurrent pyelonephritis despite antimicrobial prophylaxis require surgical treatment. Deflux injection may be considered in recipients with low-grade disease. Grade IV and V reflux are best managed with open reconstruction.

The current role of endourologic management of renal transplantation complications.

Introduction. Complications following renal transplantation include ureteral obstruction, urinary leak and fistula, urinary retention, urolithiasis, and vesicoureteral reflux. These complications have traditionally been managed with open surgical correction, but minimally invasive techniques are being utilized frequently. Materials and Methods. A literature review was performed on the use of endourologic techniques for the management of urologic transplant complications. Results. Ureterovesical anastomotic stricture is the most common long-term urologic complication following renal transplantation. Direct vision endoureterotomy is successful in up to 79% of cases. Urinary leak is the most frequent renal transplant complication early in the postoperative period. Up to 62% of patients have been successfully treated with maximal decompression (nephrostomy tube, ureteral stent, and Foley catheter). Excellent outcomes have been reported following transurethral resection of the prostate shortly after transplantation for patients with urinary retention. Vesicoureteral reflux after renal transplant is common. Deflux injection has been shown to resolve reflux in up to 90% of patients with low-grade disease in the absence of high pressure voiding. Donor-gifted and de novo transplant calculi may be managed with shock wave, ureteroscopic, or percutaneous lithotripsy. Conclusions. Recent advances in equipment and technique have allowed many transplant patients with complications to be effectively managed endoscopically.

S.T.O.N.E. nephrolithometry: novel surgical classification system for kidney calculi.

OBJECTIVE: To, first, propose a novel scoring system to standardize reporting for percutaneous nephrolithotomy because the instruments currently available to predict the percutaneous nephrolithotomy outcomes are cumbersome, not validated, and of limited clinical utility; and, second, assess and predict the stone-free rates and perioperative parameters applying S.T.O.N.E. nephrolithometry. MATERIALS AND METHODS: Five reproducible variables available from preoperative noncontrast-enhanced computed tomography were measured: stone size (S), tract length (T), obstruction (O), number of involved calices (N), and essence or stone density (E). RESULTS: A total of 117 patients were included. The mean score was 7.7 (range 4-11). The stone-free rate after the first procedure was 80%. There were 18 complications (21%). The most frequent complications were postoperative sepsis and bleeding. The S.T.O.N.E. score correlated with the postoperative stone-free status (P = .001). The patients rendered stone free had statistically significant lower scores than the patients with residual stones (6.8 vs 9.7, P = .002). Additionally, the score correlated with the estimated blood loss (P = .005), operative time (P = .001), and length of hospital stay (P = .001). CONCLUSION: The novel scoring system we have presented was found to predict treatment success and the risk of perioperative complications after percutaneous nephrolithotomy. Reproducible, standardized parameters obtained from computed tomography imaging can be used for preoperative patient counseling, surgical planning, and evaluation of surgical outcomes across institutions and within medical studies.

Colocalycostomy for repair of ureterojejunal fistula.

Calycostomy is a procedure used for an inaccessible renal pelvis during pyeloplasty. We report the first case of using an anterior calycostomy to repair a ureterojejeunal fistula in a transverse colon conduit in which the ureter and pelvis were not accessible because of intense fibrosis.

Obstructive uropathy from locally advanced and metastatic prostate cancer: an old problem with new therapies.

Despite stage migration to more organ-confined disease in the era of prostate-specific antigen, the complications of advanced prostate cancer are still relatively common. Urinary tract obstruction in advanced and metastatic prostate cancer can have a varied presentation, because it may occur in multiple anatomic locations at any point in the natural history of the disease. In all cases, management depends on the current stage of disease, technical feasibility of potential therapeutic interventions, and overall prognosis of the patient. This review highlights a practical approach to the evaluation, diagnosis, and management of obstructive uropathy from prostate cancer.

Laparoscopic retroperitoneal lymph node dissection for testicular cancer.

OBJECTIVES: Laparoscopic retroperitoneal lymph node dissection (L-RPLND) was introduced over 20 years ago as a less invasive alternative to open node dissection. In this review we summarise the indications, surgical technique and outcomes of L-RPLND in the treatment of testicular cancer. METHODS: We searched MEDLINE using the terms 'laparoscopy', 'laparoscopic', 'retroperitoneal lymph node dissection', 'RPLND' and 'testicular neoplasms'. Articles were selected on the basis of their relevance, study design and content, with an emphasis on more recent data. RESULTS: We found 14 pertinent studies, which included >1300 patients who received either L-RPLND (515) or open RPLND (788). L-RPLND was associated with longer mean operative times (204 vs. 186 min), but shorter hospital stays (3.3 vs. 6.6 days) and lower complication rates (15.6% vs. 33%). Oncological outcomes were similar between L-RPLND and open RPLND, with local relapse rates of 1.3% and 1.4%, incidence of distal progression of 3.3% and 6.1%, biochemical failure in 0.9% and 1.1% and cure rates of 100% and 99.6%, respectively. CONCLUSION: There are no randomised controlled studies comparing L-RPLND with open RPLND. A review of case and comparative series showed similar perioperative and oncological outcomes. Patients undergoing L-RPLND on average have shorter hospital stays, a quicker return to normal activity and improved cosmesis.

Percutaneous nephrostolithotomy: an assessment of costs for prone and Galdakao-modified supine Valdivia positioning.

OBJECTIVE: To examine the relative costs of prone percutaneous nephrostolithotomy (PCNL) versus PCNL performed with the patient in the Galdakao-modified supine Valdivia (GMSV) position to determine whether a cost differential exists. METHODS: We compared prone PCNL with PCNL using GMSV positioning. Cost data were obtained from the urology departmental and hospital billing offices at our institution and from the 2011 local Medicare reimbursement scales. The costs were divided into 5 major categories: surgeon fees, anesthesia fees, surgical supplies, hospital-related fees, and lost revenue. RESULTS: The overall cost of prone PCNL ranged from $23 423 to $24 463, and the cost for PCNL performed with GMSV positioning ranged from $24 725 to $25 830. The difference between the 2 positions ranged from approximately $1302 for stones ≤ 2 cm to $1367 for stones >2 cm. The lost office revenue because of the requirement for a second surgeon was estimated at $1987. CONCLUSION: Our assessment of the cost for prone versus GMSV PCNL technique found GMSV positioning to be more costly. The presence of 2 surgeons was the main driver of the cost differential, because it resulted in more equipment use, with greater instrument repair costs and higher surgeon fees. It also brings into consideration the opportunity cost of having a second surgeon in the operating room and not in the office.

Vagal nerve stimulator placement for medically refractory seizures in a child treated with phrenic nerve pacing for congenital central hypoventilation syndrome.

Congenital central hypoventilation syndrome (CCHS) is a rare, idiopathic disorder characterized by a failure of automatic respiration. Abnormalities such as seizure disorder, failure to thrive, and Hirschsprung disease have been associated with CCHS. In this report, the authors discuss the use of vagal nerve stimulation (VNS) to treat a medically refractory seizure disorder in a child who had previously undergone placement of bilateral phrenic nerve stimulators for treatment of CCHS. Concomitant use of phrenic and vagal nerve stimulators has not previously been reported in the literature. No adverse reactions were noted with both devices working. Diaphragmatic pacing (DP) was clinically unaffected by VNS. The patient experienced a marked reduction in seizure frequency and severity following vagal nerve stimulator placement. Based on this case, the authors conclude that VNS is a potentially safe and efficacious treatment option for seizure disorder associated with CCHS in patients undergoing DP.

Minimally invasive retroperitoneal lymph node dissection for testicular cancer.

Testicular cancer is the most common solid organ malignancy in young men between the ages of 15 and 35. Although much of this increase in survival can be attributed to improvements in systemic chemotherapy, surgery retains a critical role in the diagnostic and therapeutic management of testicular cancer. Laparoscopic retroperitoneal lymph node dissection is an effective staging and therapeutic procedure in patients with low-stage testicular cancer. It is an attractive alternative to the open approach, with faster recovery, improved cosmesis, and reduced post-operative morbidity driving its application. In experienced hands, it can be used in postchemotherapy patients.

Difficulties with access in percutaneous renal surgery.

Percutaneous renal surgery provides a minimally invasive approach to the kidney for stone extraction in a number of different clinical scenarios. Certain clinical cases present inherent challenges to percutaneous access to the kidney. Herein, we present scenarios in which obtaining and/or maintaining percutaneous access is difficult along with techniques to overcome the challenges commonly encountered. Also, complications associated with these challenging percutaneous renal surgeries are discussed.