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INTRODUCTION AND OBJECTIVE: Inadequate pain control is a major barrier to same-day discharge after percutaneous nephrolithotomy (PCNL). This study was designed to evaluate whether the novel thoracic erector spinae plane block (ESPB) can reduce postoperative breakthrough pain and eliminate the need for intravenous (IV) opioids after PCNL. METHODS: A prospective cohort study of adult patients undergoing percutaneous nephrolithotomy (PCNL) was conducted at our institution from May 2020 to January 2021. Patients with a history of chronic pain and opioid use were excluded from the study. Participants in the intervention group received an ultrasound-guided T11 erector spinae plane block prior to the start of the procedure. Patients were admitted postoperatively and prescribed an oral pain regimen;IV opioids were prescribed only upon request. Verbal pain score ≥7) and opioid administration within 24 hours were analyzed as the primary outcome. RESULTS: A total of 56 patients undergoing PCNL were included in our study, of whom 23 successfully received ESPB. We found that 78% of patients in the ESPB group compared to 47% in the control group were successfully managed with oral analgesics alone without IV opioids or breakthrough pain (p=0.03). Although no difference in total 24-hour opioid usage was detected, ESPB significantly lowered the odds of having breakthrough pain after adjusting for factors such as age, sex, dilated tract size, and tract location (OR 0.21, 95% CI 0.050-0.78). CONCLUSIONS: ESPB greatly reduces breakthrough pain and IV opioid use after PCNL, and most patients who receive an ESPB can be managed with oral analgesics alone. The ESPB can be performed by urologists or by the regional pain specialists as part of a routine perioperative workflow. This holds great promise in facilitating sameday discharge after PCNL, a benefit that is especially impactful in the COVID-19 era.

INTRODUCTION AND OBJECTIVE:Family history of urolithiasis is a known risk factor for kidney stones. The direct relationship between family history and the severity of clinical presentation for kidn...

Pain after percutaneous nephrolithotomy (PCNL) is thought to arise from the dilated renal tract rather than from the skin incision, and the response to traditional analgesics is typically limited.[1] To address this problem, the erector spinae plane block (ESPB) has recently been identified as safe and effective method to target kidney pain. While both T8 and T11 have been reported to be effective in relieving renal colic and surgical pain after PCNL, T11 is hypothesized to have greater ureteral coverage.[2-6].

ObjectiveTo determine if limited food access census tracts and food swamp census tracts are associated with increased risk for repeat kidney stone surgery. And to elucidate the relationship between community-level food retail environment relative to community-level income on repeat stone surgery over time.MethodsData were abstracted from the University of California, San Francisco Information Commons. Adult patients were included if they underwent at least one urologic stone procedure. Census tracts from available geographical data were mapped using Food Access Research Atlas data from the United States Department of Agriculture Economic Research Service. Kaplan-Meier curves were employed to illustrate time to a second surgical procedure over 5 years, and log-rank tests were used to test for statistically significant differences. A multivariate Cox regression model was used to generate hazard ratios for undergoing second surgery by group.ResultsA total of 1496 patients were included in this analysis. Repeat stone surgery occurred in 324 patients. Kaplan-Meier curves demonstrated a statistically significant difference in curves depicting patients living in low income census tracts (LICTs) vs those not living in LICTs (P

Introduction:Since 2014 the AUA (American Urological Association) has convened several Quality Improvement Summits to provide education and promote dialogue around issues of quality improve...

Kidney stones are a source of significant morbidity which have been shown to negatively impact health related quality of life. We sought to understand the association between health related quality of life, socioeconomic status and race among patients with kidney stones.Patients with stones at a total of 11 stone centers across the United States completed the WISQOL (Wisconsin Stone Quality of Life questionnaire). The patient ZIP Code™ was used to estimate household income. A mixed effects regression model was constructed for analysis with ZIP Code as the random intercept.A total of 2,057 stone formers completed the WISQOL. Lower income was independently associated with significantly lower health related quality of life (β = 0.372, p = 0.014), as were nonwhite race (β = -0.299, p = 0.001), unemployed work status (β = -0.291, p = 0.008), female gender (β = -0.204, p0.001), body mass index greater than 40 kg/mLower income, nonwhite race and unemployed work status were independently associated with lower health related quality of life among patients with kidney stones. While clinical characteristics such as body mass and stone disease severity were also associated with health related quality of life, this study shows that socioeconomic factors are similarly important. Further research to understand the specific mechanisms by which socioeconomic status and race impact health may lend insight into methods to optimize clinical treatment of stone formers and patients with other chronic diseases.

Protein arginine methyltransferases (PRMTs) are involved in many cellular processes via the arginine methylation of histone or non-histone proteins. We examined the expression patterns of prmt4, prmt7, and prmt9 during embryogenesis in Xenopus using whole-mount in situ hybridization and quantitative reverse transcription polymerase chain reaction (RT-PCR). Xenopus prmt4 and prmt7 were expressed in the neural crest, brain, and spinal cord, and also detected in the eye, branchial arches, and heart at the tailbud stage. Specific prmt9 signals were not detected in Xenopus embryos until the late tailbud stage when weak expression was observed in the branchial arches. Quantitative RT-PCR indicated that the expressions of prmt4 and prmt7 were up-regulated during the neurula stage, whereas prmt9 maintained its low expression until the late tailbud stage, consistent with the whole-mount in situ hybridization results. Thus, the developmental expression patterns of these three prmt genes in Xenopus embryos provide a basis for further functional study of such genes.

Protein arginine methyltransferases (PRMTs) are involved in many cellular processes via the arginine methylation of histone or non-histone proteins. We examined the expression patterns of prmt4, prmt7, and prmt9 during embryogenesis in Xenopus using whole-mount in situ hybridization and quantitative reverse transcription polymerase chain reaction (RT-PCR). Xenopus prmt4 and prmt7 were expressed in the neural crest, brain, and spinal cord, and also detected in the eye, branchial arches, and heart at the tailbud stage. Specific prmt9 signals were not detected in Xenopus embryos until the late tailbud stage when weak expression was observed in the branchial arches. Quantitative RT-PCR indicated that the expressions of prmt4 and prmt7 were up-regulated during the neurula stage, whereas prmt9 maintained its low expression until the late tailbud stage, consistent with the whole-mount in situ hybridization results. Thus, the developmental expression patterns of these three prmt genes in Xenopus embryos provide a basis for further functional study of such genes.

Primary hyperoxaluria 1 (PH1) is a devastating condition involving recurrent urolithiasis, early end-stage renal disease and multisystemic deposition of calcium oxalate crystals. Treatment options for PH1 are limited, inevitably requiring transplantation, usually combined kidney and liver transplant. Here we report successful compassionate use of Nedosiran, an RNA interference targeting lactate dehydrogenase, in an index patient. Monthly Nedosiran injections led to dramatically decreased plasma oxalate levels, decreased frequency of weekly hemodialysis sessions from 6 to 3, and deferral of combined kidney and liver transplant. Nedosiran represents a novel and impactful potential therapeutic for PH1 patients with end-stage renal disease.

Objectives: To investigate the feasibility and efficacy of live renal ultrasonography to guide Double-J ureteral stent placement at the bedside. Patients and Methods: Between April 12 and June 5, 2020, patients presenting with acute ureteral obstruction requiring decompression were prospectively selected for ultrasound-guided bedside ureteral stent placement. During stent placement, upper tract access confirmed using ultrasound with or without retrograde injection of ultrasound contrast before Double-J stent insertion. A postprocedural abdominal X-ray was obtained for stent position confirmation. Results: Eight patients (four men and four women) were offered bedside ultrasound-guided ureteral stent placement, and all eight consented to proceed. Stents were placed in seven of eight patients. One patient had an impacted ureterovesical junction stone and stricture requiring ureteroscopy and laser lithotripsy in the operating room. All patients tolerated procedures without immediate complications. Conclusion: Live renal ultrasonography can facilitate a high success rate for bedside ureteral stent placement outside the operating room. This approach is an attractive alternative to fluoroscopy-guided stent placement in the operating room and is of particular value in the COVID-19 era when judicious use of these resources is salient.

Introduction: Health-related quality of life (HRQOL) is decreased in patients with kidney stones at all stages of stone disease, even when asymptomatic. Stress is thought to contribute to HRQOL, although there has been minimal investigation into the effect of stress on stone-related quality of life (QOL). We used the Wisconsin Stone Quality of Life Questionnaire (WISQOL) to assess the relationship of stress to stone-related QOL in kidney stone patients. Methods: As part of the WISQOL Research Consortium, patients were approached in outpatient clinics and completed the WISQOL and the Perceived Stress Scale 10-item questionnaire (PSS-10). Patients with stones at enrollment were divided into those with symptoms and those without, while patients with no current stones formed another group. Questionnaire scores from each group were compared statistically and correlations between the groups were calculated. Results: Patients (n=704) were enrolled from six centers. The WISQOL successfully discriminated between patients with current stones and those without (p

Xanthogranulomatous pyelonephritis is a destructive bacterial infection typically necessitating nephrectomy. We hypothesized that long-term preoperative antibiotics would facilitate laparoscopic nephrectomy by reducing the renal inflammation.We reviewed the records of all patients with histologically confirmed xanthogranulomatous pyelonephritis at 3 University of California institutions between 2005 and 2018. Patients were stratified by antibiotic treatment duration and surgical approach. Patients treated with long-term preoperative antibiotics (28 days or more of continuous treatment until surgery) were compared to patients treated with short-term antibiotics (less than 28 days) and those who only received single-dose prophylactic antibiotics before surgery. Patient demographics and operative outcomes were analyzed. Complications were assigned by Clavien-Dindo classification.Among the 61 patients, 51 (84%) were female and mean age was 50 years. There were 21 (34%) open procedures and 40 (66%) laparoscopic procedures. Median duration of antibiotic treatment was 5 days in those who received a short-term treatment and 87 days in those who received long-term treatment. Eleven patients received only prophylactic single-dose antibiotics. Using multivariate analysis among patients undergoing laparoscopic nephrectomy, controlling for preoperative drainage, long-term antibiotics resulted in a 6.5-day shorter length of stay (p=0.023) and less overall as well as milder postoperative complications (pGreater than or equal to 4 weeks of preoperative antibiotics before laparoscopic nephrectomy for xanthogranulomatous pyelonephritis was associated with shorter length of stay and fewer, less severe postoperative complications.

Previously, we identified RAD21R450C from a peripheral sclerocornea pedigree. Injection of this rad21 variant mRNA into Xenopus laevis embryos disrupted the organization of corneal stroma fibrils. To understand the mechanisms of RAD21-mediated corneal stroma defects, gene expression and chromosome conformation analysis were performed using cells from family members affected by peripheral sclerocornea. Both gene expression and chromosome conformation of cell adhesion genes were affected in cells carrying the heterozygous rad21 variant. Since cell migration is essential in early embryonic development and sclerocornea is a congenital disease, we studied neural crest migration during cornea development in X. laevis embryos. In X. laevis embryos injected with rad21 mutant mRNA, neural crest migration was disrupted, and the number of neural crest-derived periocular mesenchymes decreased significantly in the corneal stroma region. Our data indicate that the RAD21R450C variant contributes to peripheral sclerocornea by modifying chromosome conformation and gene expression, therefore disturbing neural crest cell migration, which suggests RAD21 plays a key role in corneal stroma development.

Background Kidney stone formers (SFs) are at increased risk of stroke, myocardial infarction, and atherosclerosis of the carotid and coronary arteries. These cardiovascular and urologic pathologies can result from ectopic biomineral deposition. The objectives of this study are: (I) to evaluate risk factors for ectopic biomineralization, and (II) to characterize the overall burden of ectopic minerals in known SFs compared to non-stone formers (NSFs) matched for these risk factors. Methods Presence and quantity of biominerals at eight anatomic locations (abdominal aorta, common iliac arteries, pelvic veins, prostate or uterus, mesentery, pancreas, and spleen) were determined in a case control study by retrospective analysis of clinical non-contrast computed tomography scans obtained from 190 SFs and 190 gender- and age-matched NSFs (renal transplant donors). Predictors of biomineralization were determined using negative binomial regression. A subgroup of 140 SFs and 140 NSFs were matched for risk factors for systemic biomineralization, and mineralization was compared between these matched SFs and NSFs using ordinal logistic regression. Results Hypertension, hyperlipidemia, diabetes mellitus, and smoking were more common amongst SFs. Risk factors for increased systemic biomineralization included history of nephrolithiasis, male gender, older age, and history of hyperlipidemia. When controlling for these comorbidities, SFs had significantly increased biomineralization systemically and at the abdominal aorta, iliac arteries, prostate, mesentery, pancreas, and spleen compared to NSFs. Conclusions The current study provides evidence that SFs are at increased risk of biomineralization systemically, independent of common risk factors of atherosclerosis.

Urologists are at significant risk due to radiation exposure (RE) from endourological procedures for stone disease. Many techniques described have shown a reduction of RE. The purpose of this article is to review available protocols to decrease RE during such procedures and provide tips and tricks for their implementation. Several low-radiation and radiation-free protocols for percutaneous nephrolithotomy and flexible ureteroscopy have been described as an attempt to reduce RE during surgery. Beginning with specific checklists to ensure adequate C-arm usage, fluoroless procedures are based on endoscopic assessment, tactile guidance, and use of ultrasound to avoid fluoroscopy. A specific preoperative checklist and low radiation or complete fluoroless radiation endourological procedures have shown to be effective, feasible, and safe. It is recommended for urologists to be aware of the risks of RE and apply the “ALARA” (As Low As Reasonably Achievable) protocols.

INTRODUCTION AND OBJECTIVE:Xanthogranulomatous pyelonephritis (XGP) is a destructive bacterial infection and inflammation of the renal parenchyma, typically requiring nephrectomy. We hypothesized t...

INTRODUCTION AND OBJECTIVE:Urolithiasis affects 1 in 11 Americans, and is associated with annual health care expenditures of up to $4.5 billion. Undergoing multiple as opposed to single procedures ...

INTRODUCTION AND OBJECTIVE:Urolithiasis is associated with a decreased health-related quality of life. The Wisconsin Stone Quality of Life (WISQOL) questionnaire is a validated instrument to evalua...

INTRODUCTION AND OBJECTIVE:Many patients self-report renal colic as the worst pain of their lives. Despite extensive evidence that stone recurrence can be reduced up to 60% with behavioral changes,...

Renal access for the purpose of percutaneous nephrolithotomy can be obtained safely and accurately using a variety of techniques, instruments, and imaging modalities. This chapter describes the multiple options available to the surgeon for obtaining access, including ultrasound guidance, fluoroscopic guidance, prone or supine positioning, retrograde endoscopic combined visualization, or retrograde needle access. Surgeons must tailor their practice specific to their skills and the patient on a case by case basis.

OBJECTIVE: To define how the learning curve for success in ultrasound-guided PCNL is impacted by body mass index (BMI). Previous research has shown ultrasound-guided percutaneous nephrolithotomy (PCNL) to be an effective method of nephrolithiasis treatment comparable to fluoroscopy guided PCNL. A common concern for the ultrasound-guided approach is potential imaging difficulty in the obese patient population. METHODS: A prospective cohort study of consecutive patients undergoing PCNL with ultrasound guidance for renal tract access was performed. Clinical data collected included success in gaining renal access with ultrasound guidance, patient BMI, and clinical outcomes over time. Nonparametric LOWESS regression modeling was performed in R using locally weighted scatterplot smoother (R version 3.3.3) for gradations of patients by BMI group (40). RESULTS: A total of 150 cases were examined. Case number and BMI were evaluated as continuous variables. Multivariate logistic regression revealed that BMI (p = 0.010; OR 0.93) and case number (p40 group is downward and right-shifted relative to the other two groups. CONCLUSION: The learning curve for successful ultrasound-guided PCNL is impacted by patient BMI as well as case number. Increasing BMI makes access more challenging when performing ultrasound-guided PCNL.

To evaluate the utility of kidney injury test (KIT) assay urinary biomarkers to detect kidney stones and quantify stone burden.A total of 136 spot urine samples from 98 individuals, with and without kidney stone disease, were processed in a predefined assay to measure six DNA and protein markers in order to generate a risk score for the non-invasive detection of nephrolithiasis. From this cohort, 56 individuals had spot, non-timed urine samples collected at the time of radiographically confirmed kidney stones, and 54 demographically matched, healthy controls without kidney stone disease also provided spot, non-timed urine samples. Sixteen individuals with persistent stone disease had more than one urine sample. Using a proprietary microwell-based KIT assay, we measured cell-free DNA (cfDNA), methylated cfDNA, clusterin, creatinine, protein and CXCL10. A KIT stone score was computed across all markers using the prior locked KIT algorithm. The KIT stone score, with a scale of 0 to 100, was then correlated with demographic variables, kidney stone burden, obstructive kidney stone disease, and urine solutes in 24-h urine collections.The scaled KIT stone score, a composite of all six biomarkers, readily discriminated individuals with current or prior radiographically confirmed kidney stones from healthy controls without kidney stone disease (P0.001). In individuals with nephrolithiasis, KIT stone score also correlated with radiologically measured stone size (P = 0.017) and differentiated patients with a clinical radiological diagnosis of obstructive nephrolithiasis associated with upper renal tract dilatation (P = 0.001). Stone burden as assessed by KIT stone score, however, did not correlate with the any of the traditional measures of 24-h urine solutes or the 24-h urine supersaturation levels. In patients with persistent stone disease, where multiple urine samples were collected over time and after different interventions, the use of KIT stone score could non-invasively track stone burden over time through a spot urine, non-timed urine sample.A random, spot urine-based assay, KIT stone score, can non-invasively detect, quantify and monitor current stone burden, and may thus minimize radiographic exposure for kidney stone detection. The KIT stone score assay may also help monitor stone recurrence risk for patients with nephrolithiasis, without the requirement for 24-h urine collections.

Reusable ureteroscope durability and need for repair are significant sources of expense and inefficiency for patients and urologists. Utilization of LithoVue™, a disposable flexible digital ureteroscope, may address some of these concerns. To identify its economic impact on clinical care, we performed a micro-cost comparison between flexible reusable fiberoptic ureteroscopes (URF-P6™) and LithoVue.For this prospective, single-center micro-costing study, all consecutive ureteroscopies performed during 1 week each in July and August 2016 utilized either URF-P6 or LithoVue ureteroscopes respectively. Workflow data were collected, including intraoperative events, postoperative reprocessing cycle timing, consumables usage, and ureteroscope cost data.Intraoperative data analysis showed mean total operating room time for URF-P6 and LithoVue cases were 93.4 ± 32.3 and 73.6 ± 17.4 minutes, respectively (p = 0.093). Mean cost of operating room usage per case was calculated at $1618.72 ± 441.39 for URF-P6 and $1348.64 ± 237.40 for LithoVue based on institutional cost rates exclusive of disposables. Postoperative data analysis revealed costs of $107.27 for labor and consumables during reprocessing for URF-P6 cases. The costs of ureteroscope repair and capital acquisition for each URF-P6 case were $957.71 and $116.02, respectively. The total ureteroscope cost per case for URF-P6 and LithoVue were $2799.72 and $2852.29, respectively.Micro-cost analysis revealed that the cost of LithoVue acquisition is higher per case compared to reusable fiberoptic ureteroscopes, but savings are realized in labor, consumables, and repair. When accounting for these factors, the total cost per case utilizing these two ureteroscopes were comparable.

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.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.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.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.

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.

We compared contrast enhanced ultrasound and fluoroscopic nephrostography in the evaluation of ureteral patency following percutaneous nephrolithotomy.This prospective cohort, noninferiority study was performed after obtaining institutional review board approval. We enrolled eligible patients with kidney and proximal ureteral stones who underwent percutaneous nephrolithotomy at our center. On postoperative day 1 patients received contrast enhanced ultrasound and fluoroscopic nephrostogram within 2 hours of each other to evaluate ureteral patency, which was the primary outcome of this study.A total of 92 pairs of imaging studies were performed in 82 patients during the study period. Five study pairs were excluded due to technical errors that prevented imaging interpretation. Females slightly predominated over males with a mean ± SD age of 50.5 ± 15.9 years and a mean body mass index of 29.6 ± 8.6 kg/mA contrast enhanced ultrasound nephrostogram can be safely performed to evaluate for ureteral patency following percutaneous nephrolithotomy. This imaging technique was mostly concordant with fluoroscopic findings. Most discordance was likely attributable to the higher sensitivity for patency of contrast enhanced ultrasound compared to fluoroscopy.

The Kidney Injury Test (KIT) Stone-Score provides an objective measure of stone burden. Unlike urinary supersaturation the KIT Stone-Scores assess underlying stone disease rather than urinary solute composition. We report a case of a 43-year-old woman with no history of nephrolithiasis who underwent an elective, voluntary KIT assay and was diagnosed with a large staghorn renal stone after an unanticipated markedly elevated score. This clinical scenario highlights the potential future use of the non-invasive urinary KIT assay as a reliable non‐invasive tool to detect and monitor urinary stone disease., Highlights • KIT assay consists of a panel of six urinary biomarkers measured on a random urine sample. • Healthy asymptomatic patient was diagnosed with an unanticipated staghorn kidney stone after an elevated elective KIT assay. • For healthy patients, the threshold for the KIT Stone-Score was determined to be less than or equal to 30. • Urinary KIT normalized 6-months post-operatively. • KIT assay predicts the future risk of recurrence and risk stratify kidney stone patients.

IntroductionEndoscopic tools have provided versatile examination and treatment for kidney stone procedures. Despite endourologists researching urinary stone disease using endoscopes to collect tissue, this tissue collection method is limited. Endoscopically removed tissues are small in size, restricting the types of genome-based examination possible. We investigated a new method of renal papilla biopsy and RNA extraction to establish a genomic research methodology for kidney stone disease.Patients and methodsWe conducted a prospective multi-institutional study and collected renal papilla specimens from consecutive percutaneous nephrolithotomy and ureteroscopy (URS) cases performed for removal of upper urinary tract stones. Renal papilla tissue was extracted using ureteroscopic biopsy forceps after stone removal. RNA was extracted using two different extraction kits, and their quantity and quality were examined. Additionally, the impact of biopsy on surgical complications was compared between cases performed with and without biopsy by matched case-control analysis adjusted for age, gender, body mass index, bilaterality, and stone burden.ResultsA total of 90 biopsies from 49 patients were performed, and the median duration between specimen collection and RNA extraction was 61 days. Both univariate and multivariate analyses showed BIGopsy® forceps usage significantly increased the total yield (p = 0.004) and quality (p = 0.001 for A260/280, p = 0.004 for A260/A230) of extracted RNA. Extraction using the RNeasy Micro Kit® also improved A260/A230, whereas reduced RNA integrity number of extracted RNA by univariate and multivariate analyses (p = 0.002 and p

ObjectiveRecent studies have clarified the role of alpha-blockers, such as tamsulosin, for patients diagnosed with ureteral stones

Introduction: Polymerase chain reaction (PCR) has been a reliable molecular technology in both research and clinical fields for decades. It amplifies a minute amount of DNA or RNA sample into large quantity for target detection. Recently, a more advanced molecular manifestation, digital PCR (dPCR), has become popular in molecular diagnostics as it has potential advantages against quantitative PCR (qPCR) and this technology will become a mainstream diagnostic platform in future.Areas covered: This review describes the principle and types of dPCR, and its potential applications on different aspects and fields.Expert commentary: Digital PCR is an advanced molecular testing technology that has massive potential. Its improved accuracy and precision help diagnosing various diseases at an earlier stage, monitoring treatment in higher resolution and hence raising the recovery rate and survival rate of patients. However, to put dPCR into routine clinical application, it is very important to ensure that dPC...

Objective To examine the cost factors associated with ultrasound and fluoroscopic guidance for percutaneous nephrolithotomy (PCNL) and to determine which method can be performed at a lower cost per case. Methods A cost comparison study was performed utilizing clinical data from a prospectively maintained research database. We included the most recent 33 consecutive ultrasound-guided PCNL cases in 2016 and the most recent 40 consecutive fluoroscopy-guided PCNL cases before the operative surgeon transitioned to ultrasound guidance in May 2014. The total operative time and clinical outcomes were examined. Costs were extracted from the institution accounting systems and given a uniform multiplier to protect institutional financial reporting confidentiality. Comparisons were made using the Student t test and the chi-squared test. Results After excluding outliers, 71 PCNL procedures were included in the analysis. Demographic data and stone characteristics were not different between ultrasound-guided and fluoroscopy-guided groups. However, the mean operative time for ultrasound-guided PCNL was significantly shorter (99.8 ± 27.0 vs 144.9 ± 55.1 minutes, P

Purpose To demonstrate the feasibility of contrast material-enhanced ulrasonographic (US) nephrostograms to assess ureteral patency after percutaneous nephrolithotomy (PCNL) in this proof-of-concept study. Materials and Methods For this HIPAA-compliant, institutional review board-approved prospective blinded pilot study, patients undergoing PCNL provided consent to undergo contrast-enhanced US and fluoroscopic nephrostograms on postoperative day 1. For contrast-enhanced US, 1.5 mL of Optison (GE Healthcare, Oslo, Norway) microbubble contrast agent solution (perflutren protein-type A microspheres) was injected via the nephrostomy tube. Unobstructed antegrade ureteral flow was defined by the presence of contrast material in the bladder. Contrast-enhanced US results were compared against those of fluoroscopic nephrostograms for concordance. Results Ten studies were performed in nine patients (four women, five men). Contrast-enhanced US demonstrated ureteral patency in eight studies and obstruction in two. One patient underwent two studies, one showing obstruction and the second showing patency. Concordance between US and fluoroscopic assessments of ureteral patency was evaluated by using a Clopper-Pearson exact binomial test. These results were perfectly concordant with fluoroscopic nephrostogram results, with a 95% confidence interval of 69.2% and 100%. No complications or adverse events related to contrast-enhanced US occurred. Conclusion Contrast-enhanced US nephrostograms are simple to perform and are capable of demonstrating both patency and obstruction of the ureter. The perfect concordance with fluoroscopic results across 10 studies demonstrated here is not sufficient to establish diagnostic accuracy of this technique, but motivates further, larger scale investigation. If subsequent larger studies confirm these preliminary results, contrast-enhanced US may provide a safer, more convenient way to evaluate ureteral patency than fluoroscopy. © RSNA, 2016 Online supplemental material is available for this article.

Ultrasound-guided percutaneous nephrolithotomy (PCNL) has become increasingly utilized. Patients with nondilated collecting systems represent a challenge: the target calix is often difficult to visualize. Here we report pilot study results for retrograde ultrasound contrast injection to aid in percutaneous renal access during ultrasound-guided PCNL.From April to July 2016, consecutive patients over the age of 18 years with nondilated collecting systems on preoperative imaging who presented for PCNL were enrolled. B-mode ultrasound imaging was compared with contrast-enhanced mode with simultaneous retrograde injection of Optison™ via an ipsilateral ureteral catheter.Five patients (four males and one female) with renal stones underwent PCNL with retrograde ultrasound contrast injection during the study period. Mean body mass index was 28.3 ± 5.6 kg/mRetrograde ultrasound contrast injection as an aide for renal puncture during PCNL is a feasible technique. By improving visualization of the collecting system, it facilitates needle placement in challenging patients without hydronephrosis. Future larger scale studies comparing its use to standard ultrasound-guided technique will be required to validate this concept.

Objective To identify factors associated with successful ultrasound guidance for each surgical step of ultrasound-guided percutaneous nephrolithotomy (PCNL). Patients and Methods Consecutive patients undergoing PCNL between March 2015 and June 2016 were prospectively enrolled. An attempt was made to use ultrasound guidance in renal access, tract dilation, and nephrostomy tube placement for each patient. For steps during which ultrasound guidance was unsuccessful, fluoroscopic screening was applied. Regression analysis identified patient characteristics associated with successful use of ultrasound guidance. Results A total of 96 patients composed this cohort, with a mean body mass index of 28.7 kg/m 2 . Mean stone size was 33.1 ± 18.9 mm, and no hydronephrosis was found in 63.5% of cases. Fluoroscopic screening was required for renal access in 27 cases (28.1%), tract dilation in 38 (39.6%), and nephrostomy tube placement in 80 (83.3%). Multivariate analysis demonstrated that successful ultrasound guidance was significantly associated with the presence of hydronephrosis for renal access and the absence of staghorn calculi for tract dilation. Ultrasound-guided nephrostomy tube placement appeared linked to surgeon experience. Conclusion To achieve completely x-ray–free ultrasound-guided PCNL, the ideal patient should have a hydronephrotic collecting system with no staghorn stone present. For practitioners looking to adopt ultrasound guidance into their PCNL practice, these represent the most appropriate patients to safely initiate a surgical experience.

Context Urolithiasis has a high prevalence and recurrence rate. Prevention is key to patient management, but risk stratification is challenging. In particular, genetic predisposition for urinary stones is not fully understood. Objective To review current evidence of potential causative genes for idiopathic urolithiasis and map their relationships to one another. This evidence is essential for future establishment of molecular targeted therapy. Evidence acquisition A systematic literature review from 2007 to 2017 was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-analyses guidelines. The search was restricted to human studies conducted as either case–control or genome-wide association studies, and published in English. We also performed a causal network analysis of candidate genes gained from the systematic review using Ingenuity Pathway Analysis (IPA). Evidence synthesis During the systematic screening of literature, 30 papers were selected for the review. A total of 20 genes with 42 polymorphisms/variants were found to be associated with urolithiasis risk. Their functional roles were mainly categorized as stone matrix, calcium and phosphate regulation, urinary concentration and constitution, and inflammation/oxidative stress. IPA network analysis revealed that these genes connected via signaling pathways and a proinflammatory/oxidative environment. Conclusions This systematic review provides an updated gene list and novel causal networks for idiopathic urolithiasis risk. Although some genes such as SPP1, CASR, VDR, CLDN14, and SLC34A1 were identified by several studies and recognized by prior reviews, further investigation elucidating their roles in stone formation will be essential for future studies. Patient summary In this review, we summarized recent literature regarding genes responsible for kidney stone risk. Based on a detailed review of 30 articles and computational network analysis, we concluded that disorder of mineral regulation with local inflammation in the kidney may cause kidney stone disease.

Objective To evaluate Thiel-embalmed cadavers (TEC) as a training model for percutaneous nephrolithotomy (PCNL), more specifically for ultrasound (US)-guided supine endoscopic combined intrarenal surgery (ECIRS). Subjects and Methods Thirteen urologists (nine experienced endourologists, four fellows/residents) performed an US-guided supine ECIRS procedure on a TEC. The model was evaluated by way of a questionnaire (5-point Likert scale). Descriptive statistical analysis was performed and results were graphically presented using divergent bar graphs. Results US images were appreciated as lifelike in all aspects. Although distention of the collecting system was not ideal in one out of three TEC, US visualisation of the distended calyces during puncture was good. Skin penetration was more difficult and less realistic in TEC, while kidney puncture and dilatation were deemed very realistic. Ureteric and collecting system anatomy and consistency were similar to real life, although the mucosa appeared paler. US needle guidance was perceived as excellent. Overall, needle puncture assessment was realistic and useful as a training tool. Overall quality and satisfaction of TEC in US-guided supine ECIRS was good to excellent and comparable to a real-life procedure. Overall appropriateness of the TEC model was considered excellent for both initial and advanced supine PCNL training. Conclusion Despite the minor drawbacks of tough skin and non-ideal collecting system dilatation during ureteroscopy, the TEC model was considered good to excellent as a training model for US-guided PCNL, in particular, US-guided needle puncture of the kidney during supine ECIRS.