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Purpose: The increasing incidence of nephrolithiasis underscores the need for effective, accessible tools to aid urologists in preventing recurrence. Despite dietary modification's crucial role in prevention, targeted dietary counseling using 24-hour urine collections is underutilized. This study evaluates ChatGPT-4, a multimodal large language model, in analyzing urine collection results and providing custom dietary advice, exploring the potential for artificial intelligence-assisted analysis and counseling. Materials and Methods: Eleven unique prompts with synthesized 24-hour urine collection results were submitted to ChatGPT-4. The model was instructed to provide five dietary recommendations in response to the results. One prompt contained all "normal" values, with subsequent prompts introducing one abnormality each. Generated responses were assessed for accuracy, completeness, and appropriateness by two urologists, a nephrologist, and a clinical dietitian. Results: ChatGPT-4 achieved average scores of 5.2/6 for accuracy, 2.4/3 for completeness, and 2.6/3 for appropriateness. It correctly identified all "normal" values but had difficulty consistently detecting abnormalities and formulating appropriate recommendations. The model performed particularly poorly in response to calcium and citrate abnormalities and failed to address 3/10 abnormalities entirely. Conclusions: ChatGPT-4 exhibits potential in the dietary management of nephrolithiasis but requires further refinement for dependable performance. The model demonstrated the ability to generate personalized recommendations that were often accurate and complete but displayed inconsistencies in identifying and addressing urine abnormalities. Despite these limitations, with precise prompt design, physician oversight, and continued training, ChatGPT-4 can serve as a foundation for personalized medicine while also reducing administrative burden, indicating its promising role in improving the management of conditions such as nephrolithiasis.

Background: Overweight/obesity is considered an independent risk factor for nephrolithiasis, but little is known about its effect on nephrolithiasis according to metabolic health status., Objectives: We aimed to investigate the association between various metabolic overweight phenotypes and the occurrence of nephrolithiasis. It also explores whether changes in these phenotypes over time influence the risk of nephrolithiasis., Materials and Methods: A total of 10,315 participants free of nephrolithiasis who underwent an annual health checkup from 2017 to 2022 were included in our prospective cohort study. They were categorized into four groups according to the presence of overweight and metabolic abnormalities (MA). The primary endpoint was the occurrence of renal stones. Multivariable Cox analysis was conducted to elucidate the relationship between metabolic overweight phenotypes and incident nephrolithiasis., Results: During a median follow-up duration of 4.02 years, nephrolithiasis occurred in 1,468 (14.23%) participants. In the full cohort, we observed that the 5-year cumulative incidences of nephrolithiasis were highest in the metabolically healthy overweight (MHO) and metabolically abnormal overweight (MAO) groups. The hazard ratios (HRs) for nephrolithiasis, relative to metabolically healthy normal weight (MHNW), ranged from 1.19 (95% CI:1.03-1.37; MHO) to 1.32 (95% CI:1.15-1.51; MAO). Furthermore, individuals with persistent MHO throughout follow-up were at a 1.42-fold increased risk of nephrolithiasis (P < 0.001), and 32.17% of individuals experienced changes in phenotype during follow-up. Among MAO subjects, those who transitioned to MHO and MHNW had a 26% and 45% lower risk of incident nephrolithiasis, respectively, compared to those who persisted in the MAO phenotype., Conclusion: Individuals in the MHO and MAO groups exhibit an elevated risk of incident nephrolithiasis in this prospective cohort study. A significant proportion of nephrolithiasis cases may be potentially preventable through the appropriate management of metabolic risk factors for MAO subjects., (© 2024. The Author(s).)

Urinary stones are a growing disease that results from pathological biomineralization. Cassia fistula Lin. is traditionally used to treat urinary stones. However, no scientific evidence is available to prove its antilithiatic effect. This study evaluates the antilithiatic potential of aqueous and ethanolic extract of Cassia fistula Lin. fruit (Cff) against calcium oxalate kidney stones. Forty-two male Wistar rats were divided into seven groups (n = 6/group): Group I (control), Group II (rats treated with ethylene glycol and ammonium chloride developed nephrolithiasis after 28 days), Group III (lithiatic rats receiving distilled water for 30 days), Group IV and V (lithiatic rats receiving aqueous extract of Cff at doses of 1 and 100 mg/kg body weight for 30 days, respectively) and Group VI and VII (lithiatic rats receiving ethanolic extract of Cff at doses of 1 and 100 mg/kg body weight for 30 days, respectively). Some parameters of urine and serum, and also renal oxidative stress and histopathology were used to determine the antilithiatic effect of aqueous and ethanolic extract of Cff. Therefore, the types of extracts of Cff improved abnormal levels of urine, serum, and renal oxidative stress and histopathology parameters. This antilithiatic effect of aqueous and ethanolic extracts of Cff, can be attributed to the anti-crystallization and antioxidant properties of the extracts and the ability to improve urine and serum biochemistry. RESEARCH HIGHLIGHTS: Ethylene glycol and ammonium chloride-induced urolithiasis, aggregation of calcium oxalate deposits, increase of some urinary and serum parameters, relative kidney weight, kidney size and MDA activity, decrease of some urinary parameters, relative body weight and SOD activity. Aqueous and ethanolic extracts of Cassia fistula Lin. lead to the treatment of urolithic rats by decreasing levels of urinary oxalate, phosphate, urea, serum urea, uric acid, creatinine, calcium, phosphate, MDA, kidney weight and kidney size, increasing levels of urinary calcium, creatinine, magnesium, citrate, body weight and SOD activity in the kidney, eliminating CaOx deposition (esp. ethanolic extract)., (© 2024 Wiley Periodicals LLC.)

Background: Certain occupations may predispose individuals to urolithiasis, a multi-factorial disease. The study aimed to evaluate the prevalence and related factors of nephrolithiasis in medical staff in Qingdao, China., Methods: Physical examination results of 5115 in-service medical staff aged 22-60 years old were retrospectively analyzed. Multivariable logistic regression analysis and stratified analyses by age and gender were applied to explore the related factors of nephrolithiasis in these medical staff., Results: The overall nephrolithiasis prevalence in medical staff in Qingdao, China was 4.65%. Doctors were more prone to nephrolithiasis than nurses (5.63% vs. 3.96%, P = 0.013) and the peak prevalence (6.69%) was observed in medical staff working in the emergency department (ED). Male gender (OR = 1.615, 95% CI = 1.123-2.323, P = 0.010), overweight or obesity (OR = 1.674, 95% CI = 1.266-2.214, P < 0.001), work seniority ≥ 10 years (OR = 2.489, 95%CI = 1.675-3.699, P < 0.001) and working in the ED (OR = 1.815, 95% CI = 1.202-2.742, P = 0.005) were independent predictors for nephrolithiasis in medical staff based on the results of multivariate logistic regression analysis. The associations between overweight or obesity and nephrolithiasis risk as well as between work seniority ≥ 10 years and nephrolithiasis risk in medical staff were independent of age or gender in stratified analysis., Conclusions: Nephrolithiasis prevalence in medical staff in Qingdao, China seemed not to be higher than that in the general population. Medical staff with work seniority ≥ 10 years and working in the ED should pay abundant attention to take measures to modify their nephrolithiasis risk., (© 2024. The Author(s).)

Objective: To analyze the association between the triglyceride-glucose (TyG) index and the risk of nephrolithiasis across various demographic and clinical subgroups, aiming to enhance early diagnosis and treatment of nephrolithiasis and promote personalized care in diverse populations., Methods: This cross-sectional study analyzed the medical records of 84 968 adults, stratified into three categories (low, middle, high) according to their TyG index scores. To evaluate the association between the TyG index and nephrolithiasis risk, multivariable Logistic regression models were employed, adjusting for potential confounders. Additionally, piecewise linear regression models were used to investigate the non-linear dynamics of the TyG index's relationship with nephrolithiasis risk. Subgroup analyses were performed to explore variations in the effects of the TyG index across different demographic and clinical populations., Results: Increasing TyG index was associated with a higher risk of nephrolithiasis, rising from 4.36% in the low group to 8.96% in the high group ( P < 0.001). In adjusted models, males in the middle and high TyG index categories demonstrated significantly elevated risks of nephrolithiasis, with odds ratios of 1.18 (95% CI : 1.07-1.31, P =0.002) and 1.29 (95% CI : 1.15-1.45, P < 0.001), respectively. Conversely, in females, the association was not statistically significant post-adjustment ( OR =0.98, 95% CI : 0.82-1.16, P =0.778). Among males, for each unit increment in the TyG index below the critical threshold of 8.98, there was a notable 40% escalation in the risk of developing nephrolithiasis ( OR =1.40, 95% CI : 1.24-1.58, P < 0.001). Surpassing this threshold, the TyG index no longer conferred a significant increase in risk ( OR =0.91, 95% CI : 0.78-1.06, P =0.24). Subgroup analyses indicated that this association remained stable regardless of age, BMI, or hypertension status., Conclusion: The TyG index is positively associated with the risk of nephrolithiasis in males, demonstrating a nonlinear dose-response relationship that becomes especially pronounced at certain index levels. This biomarker could potentially serve as a valuable clinical tool for identifying males who are at a high risk of developing nephrolithiasis, thereby enabling targeted preventive strategies. Further research is urgently needed to explore the underlying mechanisms and to verify the applicability of these results across different populations.

Background: We aimed to investigate the prevalence, characteristics, and management of nephrolithiasis in primary hyperparathyroidism (PHPT) patients., Methods: Medical records of patients who underwent parathyroidectomy at a tertiary care hospital in British Columbia from January 2016 to April 2023 were retrospectively reviewed. Demographic data, laboratory results, imaging reports, and urologic consultations were examined. Descriptive statistics and relevant statistical tests, including logistic regressions, were utilized for data analysis., Result: Of the 413 PHPT patients included in the study population, 41.9% harbored renal stones, and nearly half (48.6%) required urological interventions. Male sex, elevated preoperative serum ionized calcium (iCa) and 24-h urinary calcium (24 ​h urine Ca) levels were independent risk factors for stone formation. Additionally, male sex, younger age, and lower preoperative serum 25-hydroxyvitamin D (25(OH)D) level were associated with higher odds of requiring urological intervention for stones., Conclusions: This study identified significant prevalence of asymptomatic renal calcifications in PHPT patients, with a substantial proportion necessitating urological intervention. These findings emphasize the importance of incorporating screening and treatment of renal stones into the management of PHPT patients., Competing Interests: Declaration of competing interest The authors do not report any conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Purpose: To investigate the incidence of nephrolithiasis in a cohort of children with congenital adrenal hyperplasia (CAH), and to study if there is an association with the metabolic control of the disease., Methods: This study was designed as a multicenter 1 year-prospective study involving 52 subjects (35 males) with confirmed molecular diagnosis of CAH due to 21-hydroxylase deficiency (21-OHD). Each patient was evaluated at three different time-points: T0, T1 (+6 months of follow-up), T2 (+12 months of follow up). At each follow up visit, auxological data were collected, and adrenocorticotrophic hormone (ACTH), 17-hydroxyprogesterone (17-OHP), Δ4-androstenedione, dehydroepiandrosterone sulfate (DHEAS) serum levels, and urinary excretion of creatinine, calcium, oxalate and citrate were assayed. Moreover, a renal ultrasound was performed., Results: The incidence of nephrolithiasis, assessed by ultrasound was 17.3% at T0, 13.5% at T1 and 11.5% at T2. At T0, one subject showed nephrocalcinosis. In the study population, a statistically significant difference was found for 17-OHP [T0: 11.1 (3.0-25.1) ng/mL; T1: 7.1 (1.8-19.9) ng/mL; T2: 5.9 (2.0-20.0) ng/mL, p < 0.005], and Δ4-androstenedione [T0: 0.9 (0.3-2.5) ng/mL; T1: 0.3 (0.3-1.1) ng/mL; T2: 0.5 (0.3-1.5) ng/mL, p < 0.005] which both decreased over the follow up time. No statistically significant difference among metabolic markers was found in the group of the subjects with nephrolithiasis, even if 17-OHP, DHEAS and Δ4-androstenedione levels showed a tendency towards a reduction from T0 to T2. Principal component analysis (PCA) was performed to study possible hidden patterns of associations/correlations between variables, and to assess the trend of them during the time. PCA revealed a decrease in the amount of the variables 17-OHP, Δ4-androstenedione, and ACTH that occurred during follow-up, which was also observed in subjects showing nephrolithiasis., Conclusions: our data demonstrated that children affected with 21-OHD can be at risk of developing nephrolithiasis. Additional studies are needed to clarify the pathogenesis and other possible risk factors for this condition, and to establish if regular screening of kidney ultrasound in these patients can be indicated., (© 2024. The Author(s).)

Background: The objective of this study was to explore the frequency of occurrence of extra-renal manifestations associated with monogenic nephrolithiasis., Methods: A literature review was conducted to identify genes that are monogenic causes of nephrolithiasis. The Online Mendelian Inheritance in Man (OMIM) database was used to identify associated diseases and their properties. Disease phenotypes were ascertained using OMIM clinical synopses and sorted into 24 different phenotype categories as classified in OMIM. Disease phenotypes caused by the same gene were merged into a phenotypic profile of a gene (PPG) such that one PPG encompasses all related disease phenotypes for a specific gene. The total number of PPGs involving each phenotype category was measured, and the median phenotype category was determined. Phenotype categories were classified as overrepresented or underrepresented if the number of PPGs involving them was higher or lower than the median, respectively. Chi-square test was conducted to determine whether the number of PPGs affecting a given category significantly deviated from the median., Results: Fifty-five genes were identified as monogenic causes of nephrolithiasis. A total of six significantly overrepresented and three significantly underrepresented phenotype categories were identified (p < 0.05). Four phenotypic categories (growth, neurological, skeletal, and abdomen/gastrointestinal) are significantly overrepresented after Bonferroni correction for multiple comparisons (p < 0.002). Among all phenotypes, impaired growth is the most common manifestation., Conclusion: Recognizing the extra-renal manifestations associated with monogenic causes of kidney stones is critical for earlier diagnosis and optimal care in patients., (© 2023. The Author(s), under exclusive licence to International Pediatric Nephrology Association.)

Sarcoidosis is a systemic inflammatory disorder characterized by granuloma formation in various organs. It has been associated with nephrolithiasis. The vitamin K epoxide reductase complex subunit 1 ( VKORC1 ) gene, which plays a crucial role in vitamin K metabolism, has been implicated in the activation of proteins associated with calcification, including in the forming of nephrolithiasis. This study aimed to investigate the VKORC1 C1173T polymorphism (rs9934438) in a Dutch sarcoidosis cohort, comparing individuals with and without a history of nephrolithiasis. Retrospectively, 424 patients with sarcoidosis were divided into three groups: those with a history of nephrolithiasis (Group I: n = 23), those with hypercalcemia without nephrolithiasis (Group II: n = 38), and those without nephrolithiasis or hypercalcemia (Group III: n = 363). Of the 424 sarcoidosis patients studied, 5.4% had a history of nephrolithiasis (Group I), only two of whom possessed no VKORC1 polymorphisms (OR = 7.73; 95% CI 1.79-33.4; p = 0.001). The presence of a VKORC1 C1173T variant allele was found to be a substantial risk factor for the development of nephrolithiasis in sarcoidosis patients. This study provides novel insights into the genetic basis of nephrolithiasis in sarcoidosis patients, identifying VKORC1 C1173T as a potential contributor. Further research is warranted to elucidate the precise mechanisms and explore potential therapeutic interventions based on these genetic findings.

Background: Calcium oxalate monohydrate (COM) forms the most common type of kidney stones observed in clinics, elevated levels of urinary oxalate being the principal risk factor for such an etiology. The objective of the present study was to evaluate the anti-nephrolithiatic effect of herbo-mineral formulation, Lithom., Methods: The in vitro biochemical synthesis of COM crystals in the presence of Lithom was performed and observations were made by microscopy and Scanning Electron Microscope (SEM) based analysis for the detection of crystal size and morphology. The phytochemical composition of Lithom was evaluated by Ultra-High-Performance Liquid Chromatography (UHPLC). The in vivo model of Ethylene glycol-induced hyperoxaluria in Sprague-Dawley rats was used for the evaluation of Lithom. The animals were randomly allocated to 5 different groups namely Normal control, Disease control (ethylene glycol (EG), 0.75%, 28 days), Allopurinol (50 mg/kg, q.d. ), Lithom (43 mg/kg, b.i.d. ), and Lithom (129 mg/kg, b.i.d. ). Analysis of crystalluria, oxalate, and citrate levels, oxidative stress parameters (malondialdehyde (MDA), catalase, myeloperoxidase (MPO)), and histopathology by hematoxylin and eosin (H&E) and Von Kossa staining was performed for evaluation of Lithom., Results: The presence of Lithom during COM crystals synthesis significantly reduced the average crystal area, feret's diameter, and area-perimeter ratio, in a dose-dependent manner. SEM analysis revealed that COM crystals synthesized in the presence of 100 and 300 μg/mL of Lithom exhibited a veritable morphological transition from irregular polygons with sharp edges to smoothened smaller cuboid polygons. UHPLC analysis of Lithom revealed the presence of Trigonelline, Bergenin, Xanthosine, Adenosine, Bohoervinone B, Vanillic acid, and Ellagic acid as key phytoconstituents. In EG-induced SD rats, the Lithom-treated group showed a decrease in elevated urinary oxalate levels, oxidative stress, and renal inflammation. Von Kossa staining of kidney tissue also exhibited a marked reduction in crystal depositions in Lithom-treated groups., Conclusion: Taken together, Lithom could be a potential clinical-therapeutic alternative for management of nephrolithiasis.

Background: Three types of primary hyperoxaluria (PH) are recognized. However, data on PH type 2 (PH2), caused by defects in the GRHPR gene, are limited., Methods: We reviewed the medical records of patients < 18 years of age with genetically-proven PH2 from seven centres across India to identify the age of onset, patterns of clinical presentation, short-term outcomes and genetic profile, and to determine if genotype-phenotype correlation exists., Results: We report 20 patients (all with nephrolithiasis or nephrocalcinosis) diagnosed to have PH2 at a median (IQR) age of 21.5 (7, 60) months. Consanguinity and family history of kidney stones were elicited in nine (45%) and eight (40%) patients, respectively. The median (IQR) serum creatinine at PH2 diagnosis was 0.45 (0.29, 0.56) mg/dL with the corresponding estimated glomerular filtration rate being 83 (60, 96) mL/1.73 m 2 /min. A mutational hotspot (c.494 G > A), rare in Caucasians, was identified in 12 (60%) patients. An intronic splice site variant (c.735-1G > A) was noted in five (25%) patients. Four (20%) patients required surgical intervention for stone removal. Major adverse kidney events (mortality or chronic kidney disease (CKD) stages 3-5) were noted in six (30%) patients at a median (IQR) follow-up of 12 (6, 27) months. Risk factors for CKD progression and genotype-phenotype correlation could not be established., Conclusions: PH2 should no longer be considered an innocuous disease, but rather a potentially aggressive disease with early age of presentation, and possible rapid progression to CKD stages 3-5 in childhood in some patients. A mutational hotspot (c.494 G > A variant) was identified in 60% of cases, but needs further exploration to decipher the genotype-phenotype correlation., (© 2023. The Author(s), under exclusive licence to International Pediatric Nephrology Association.)

Purpose: Oral chemolysis is an effective and non-invasive treatment for uric acid urinary stones. This study aimed to classify urinary stones into either pure uric acid (pUA) or other composition (Others) using non-contrast-enhanced computed tomography scans (NCCTs)., Methods: Instances managed at our institution from 2019 to 2021 were screened. They were labeled as either pUA or Others based upon composition analyses, and randomly split into training or testing data set. Several instances contained multiple NCCTs which were all collected. In each of NCCTs, individual urinary stone was treated as individual sample. From manually drawn volumes of interest, we extracted original and wavelet radiomics features for each sample. The most important features were then selected via the Least Absolute Shrinkage and Selection Operator for building the final model on a Support Vector Machine. Performance on the testing set was evaluated via accuracy, sensitivity, specificity, and area under the precision-recall curve (AUPRC)., Results: There were 302 instances, of which 118 had pUA urinary stones, generating 576 samples in total. From 851 original and wavelet radiomics features extracted for each sample, 10 most important features were ultimately selected. On the testing data set, accuracy, sensitivity, specificity, and AUPRC were 93.9%, 97.9%, 92.2%, and 0.958, respectively, for per-sample prediction, and 90.8%, 100%, 87.5%, and 0.902, respectively, for per-instance prediction., Conclusion: The machine learning algorithm trained with radiomics features from NCCTs can accurately predict pUA urinary stones. Our work suggests a potential assisting tool for stone disease treatment selection., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Unhealthy dietary habits play a key role in the pathogenesis of nephrolithiasis (NL). The aims of this case-control study were to evaluate (i) the adherence to the Mediterranean Diet (MD) and the dietary salt intake in stone-forming patients (SF), (ii) the relationship occurring between MD adherence, salt intake and NL-related metabolic risk factors in SF, and (iii) the impact of combined high MD adherence and low salt intake on NL susceptibility. From 1 January 2018 to 31 December 2019, we recruited all SF consecutively referred to the Extracorporeal Shock Wave Lithotripsy (ESWL) center of Federico II University, and at least two control subjects without a personal history of NL, age-, sex-, and body mass index-matched to SF (NSF). All study participants were interviewed using the validated MEDI-LITE and MINISAL questionnaires. In an SF subgroup, the NL-related metabolic risk factors were also evaluated. SF showed a lower MD adherence and a higher salt intake compared with NSF. The NL susceptibility decreased by 36% [OR: 0.64 (0.59-0.70); p < 0.01] for each point of increase in MEDI-LITE score, while it increased by 13% [OR: 1.13 (1.03-1.25); p = 0.01] for each point of increase in MINISAL score. The SF prevalence was higher among subjects showing combined low MD adherence and high salt intake. In SF, the MEDI-LITE score directly correlated with 24 h-citraturia, whereas the MINISAL score directly correlated with urinary sodium and uric acid excretion. In conclusion, high MD adherence and low salt intake are associated with a reduced NL susceptibility, both separately and in combination.

Purposes: Our aim is to build and evaluate models to screen for clinically significant nephrolithiasis in overweight and obesity populations using machine learning (ML) methodologies and simple health checkup clinical and urine parameters easily obtained in clinics., Methods: We developed ML models to screen for clinically significant nephrolithiasis (kidney stone > 2 mm) in overweight and obese populations (body mass index, BMI ≥ 25 kg/m 2 ) using gender, age, BMI, gout, diabetes mellitus, estimated glomerular filtration rate, bacteriuria, urine pH, urine red blood cell counts, and urine specific gravity. The data were collected from hospitals in Kaohsiung, Taiwan between 2012 and 2021., Results: Of the 2928 subjects we enrolled, 1148 (39.21%) had clinically significant nephrolithiasis and 1780 (60.79%) did not. The testing dataset consisted of data collected from 574 subjects, 235 (40.94%) with clinically significant nephrolithiasis and 339 (59.06%) without. One model had a testing area under curve of 0.965 (95% CI, 0.9506-0.9794), a sensitivity of 0.860 (95% CI, 0.8152-0.9040), a specificity of 0.947 (95% CI, 0.9230-0.9708), a positive predictive value of 0.918 (95% CI, 0.8820-0.9544), and negative predictive value of 0.907 (95% CI, 0.8756-0.9371)., Conclusion: This ML-based model was found able to effectively distinguish the overweight and obese subjects with clinically significant nephrolithiasis from those without. We believe that such a model can serve as an easily accessible and reliable screening tool for nephrolithiasis in overweight and obesity populations and make possible early intervention such as lifestyle modifications and medication for prevention stone complications., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: In urology, ureteral stents are used to treat obstructive diseases. Hematuria (54%), fever, discomfort, and lower urinary system symptoms are the predominant symptoms related to ureteral stent., Aim: This article links stent symptoms to double-j width and length, as well as patient's height, weight, and body mass index (BMI). Ureteric Stent Symptoms Questionnaire (USSQ) was used to measure ureteral stent symptoms at 1st and 4th week of stent in situ as well as the 4th week after pigtail removal., Methods: A 200-patient prospective study, where patients were allocated into four groups following ureteral stent insertion depending on the stent characteristics. Those groups were: 4.8 Fr./26 cm (Group A), 4.8 Fr./28 cm (Group B), 6 Fr/26 cm (Group C), and 6 Fr/28 cm (Group D)., Results: Men comprised 53.5% of 200 patients. Participants had an average age of 49 ± 15.5 years, height of 175 ± 8.94 cm, and BMI of 23.8 ± 7.6 cm. The laboratory results were identical between groups. At the first and fourth week, groups had similar urine symptoms, pain severity, health status and occupational activities. The difference in pain location was statistically significant. Group A had 82.4% renal back pain in the first week, whereas Group B had 68.8%, Group C 31.3% and Group D 62.5 (p=0.04). At the fourth week, 64.7% of Group A patients reported kidney front pain, compared to 100% of Group B, 93.3% of Group C, and 100% of Group D (p=0.04). There was statistical significance in the sexual activity of the patients. 24.4% of Group C patients stopped sexual activity before stent installation, compared to 10.6%, 8.3%, and 6.4% of the other groups (p=0.03). A moderate percentage of patients had active sexual activity at week 4 (Group A: 7.8%, Group B: 5.8%, Group C: 8.2%, Group D: 4.1%), p=0.83. In multivariate analysis, urinary catheter group, age, weight, height, and BMI did not significantly affect urine index score (UIS), pain index score (PIS), general health (GH), quality of work (QW), and quality of sex (QS)., Conclusions: Despite various attempts to establish the best ureteral stent, the effect of double-j stent physical features on stent-related symptoms remained unknown. No verdict is conceivable without adequate empirical data.

Introduction: Following the COVID-19 pandemic, telehealth usage increased. Virtual visits minimize exposure risk while also addressing barriers to care. Telehealth offers the ability to increase patient access and provider efficiency. However, patient satisfaction with telehealth has not been fully determined. This study evaluated patient-perceived quality and satisfaction of virtual vs face-to-face visits during consultation with a dietician in the management of nephrolithiasis., Methods: Ninety-six patients with previous diagnosis of nephrolithiasis underwent an initial, in-person nutrition consultation between May 2019 to February 2021. A follow-up with a dietician was randomized to in-person or telehealth. The telehealth group used an application called MDLive. The telehealth group used MDLive on a hospital computer during their follow-up with the urologist, whereas the in-person group had a separate appointment scheduled at a different location. Patient satisfaction following telehealth visits was assessed by the Telemedicine Satisfaction Questionnaire. Patient satisfaction following in-person visits was assessed with an 8-question modified Telemedicine Satisfaction Questionnaire, which lacked technology-related questions., Results: Fifty patients were randomized to in-person follow-up and 46 to virtual follow-up. Within the virtual follow-up group more than 90% "agreed" or "strongly agreed" that they were satisfied with the quality of service provided through telemedicine. Greater than 82% reported intention to use telemedicine services again. There was no significant difference in patient satisfaction between telemedicine and face-to-face visits. Sixty-seven percent of patients in the telemedicine group reported better access to health care services and time saved and 89% reported independence accessing the telehealth system without assistance., Conclusions: This study supports the idea that telemedicine may be a successful alternative in the follow up of patients undergoing nutritional counseling for stone prevention. Future studies regarding telehealth use should evaluate which other urologic conditions are amenable to virtual management.

Competing Interests: The authors declare no relevant conflicts of interest.

Objective: The present study compared the clinical features of patients with primary Sjögren's syndrome (pSS) with and without nephrolithiasis and/or nephrocalcinosis to determine factors related to renal dysfunction., Methods: The clinical features of 68 patients with anti-Sjogren's syndrome antigen A (SSA)/Ro-antibody-positive pSS with and without nephrolithiasis and/or nephrocalcinosis who underwent abdominal computed tomography and/or ultrasonography were retrospectively analysed., Results: Of the 68 patients with anti-SSA-antibody-positive pSS, 23 (33%) had renal nephrolithiasis and/or nephrocalcinosis, whereas 45 (67%) did not. Fourteen (20%) patients had renal dysfunction at diagnostic imaging. Among five patients who underwent renal biopsy, four patients with renal nephrolithiasis and/or nephrocalcinosis were diagnosed with tubulointerstitial nephritis, and one without nephrolithiasis and/or nephrocalcinosis was diagnosed with minimal change nephrotic syndrome. Estimated glomerular filtration rate at diagnostic imaging was significantly lower in patients with than without nephrolithiasis and/or nephrocalcinosis group (P = 0.010). In addition to nephrolithiasis and/or nephrocalcinosis (odds ratio [OR], 3.467; P = 0.045), the gap between serum sodium and chloride concentrations (OR, 10.400; P = 0.012) and increased urinary β2-microglobulin (OR, 5.444; P = 0.033) were associated with renal dysfunction at the time of diagnostic imaging., Conclusion: Nephrolithiasis and/or nephrocalcinosis, normal anion gap metabolic acidosis, and tubulointerstitial damage are associated with renal dysfunction in patients with pSS., (© Japan College of Rheumatology 2023. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Aims: The primary objective of this study was to investigate the relationship between the platelet/high-density lipoprotein cholesterol ratio (PHR) and the prevalence of nephrolithiasis within the adult population of the United States., Methods: The data used in this study were obtained from the National Health and Nutrition Examination Survey (NHANES) conducted between 2007 and 2018. The analysis included a non-pregnant population aged 20 years or older, providing proper PHR index and nephrolithiasis data. The research utilized subgroup analyses and weighted univariate and multivariable logistic regression to evaluate the independent association between the PHR and the susceptibility to nephrolithiasis., Results: The study comprised 30,899 participants with an average PHR value of 19.30 ± 0.11. The overall prevalence rate of nephrolithiasis was estimated at 9.98% with an increase in the higher PHR tertiles (T1, 8.49%; T2, 10.11%; T3, 11.38%, P < 0.0001). An elevated PHR level was closely linked with a higher susceptibility to nephrolithiasis. Compared with patients in T1, and after adjusting for potential confounders in model 2, the corresponding odds ratio for nephrolithiasis in T3 was 1.48 (95% CI: 1.06 to 2.08), with a P -value = 0.02. The results of the interaction tests revealed a significant impact of chronic kidney disease on the relationship between PHR and nephrolithiasis. Furthermore, the restricted cubic spline analyses exhibited a positive, non-linear correlation between PHR and the risk of nephrolithiasis., Conclusion: A convenient biomarker, the PHR, was independently associated with nephrolithiasis and could be a novel biomarker in predicting occurrence in clinical decision., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Ni, Lv, Wu and Xu.)

Introduction: Kidney stone disease in children is rising disproportionate to the general population, representing a disease population with a distinct biological mechanism as compared to adults. Factors influencing recurrent kidney stone disease in children are poorly characterized and the associations of the intestinal microbiome within sub-populations of kidney stone formers, however, are not well described. We evaluated a pilot cohort of children with nephrolithiasis comparing patients based on recurrent kidney stone episodes and abnormal 24-h urinary parameters, with dual aims to compare the microbiome signal in children with initial and recurrent nephrolithiasis and to explore additional associations in microbiome composition and diversity within this population., Methods: Children aged 6-18 with a history of nephrolithiasis, without an active ureteral calculus or antibiotic exposure within 30 days of study entry were eligible to participate. All participants had a 24-h urine study within 6 months of study entry and provided a fecal sample. Microbiome samples were analyzed using 16S ribosomal DNA sequencing techniques for alpha and beta diversity comparing initial and recurrent stone formers as well as microbiome multivariate association (MaAsLin2) to determine differentially abundant taxa. Shotgun sequencing reads were aligned to custom oxidase degradation and butyrate production gene databases (5 databases total). Comparisons for MaAsLin2 and shotgun metagenomics, normalized to sequencing depth, were based on stone recurrence, sex, hypercalcuria (≤4 mg/kg/day), hyperoxaluria (≥45 mg/1.73 m 2 ), and hypocitraturia (<310 mg/1.73 m 2 [females] or < 365 mg/1.73 m 2 [males])., Results: A total of 16 enrolled children provided samples sufficient for analyses, including 9 girls and 7 boys, of whom 5 had experienced recurrent kidney stone events. Three participants had hypercalcuria, 2 had hyperoxaluria, and 4 had hypocitraturia. Comparisons of Formyl-CoA transferase between index and recurrent urinary stone disease revealed a trend towards higher mean abundance of the gene in initial stone formers (0.166% vs 0.0343%, p = 0.2847) (Summary Figure), while trends toward lower biodiversity were also noted in the recurrent stone cohort on both Faith (p = 0.06) and Shannon (p = 0.05) indices. Exploratory analyses found Eubacterium siraeum to be significantly greater in relative abundance in children with documented hypercalciuria (p = 0.001)., Discussion: Our pilot study demonstrates possible signals in both microbial diversity and oxalate gene expression, both of which are lower in recurrent pediatric kidney stone patients. These findings warrant further investigation as a potential diagnostic marker for future kidney stone events., Competing Interests: Conflict of interest Dr. Ellison is a consultant to Alnylam Pharmaceuticals. None of the other authors have conflicts of interest to report., (Copyright © 2023 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

Background: Primary hyperoxaluria type 1 (PH1) is an autosomal recessive inborn error of metabolism that causes oxalate deposition, leading to recurrent calcium oxalate kidney stones, chronic kidney disease and systemic oxalosis, which produces a broad range of serious life-threatening complications. Patients with PH1 have delayed diagnosis due to the rarity of the disease and the overlap with early-onset kidney stone disease not due to primary hyperoxaluria., Objective: The objective of this study was to determine the clinical features of individuals <21 years of age with PH1 that precede its diagnosis. We hypothesized that a parsimonious set of features could be identified that differentiate patients with PH1 from patients with non-primary hyperoxaluria-associated causes of early-onset kidney stone disease., Study Design: We determined the association between clinical characteristics and PH1 diagnosis in a case-control study conducted between 2009 and 2021 in PEDSnet, a clinical research network of eight US pediatric health systems. Each patient with genetically confirmed PH1 was matched by sex and PEDSnet institution to up to 4 control patients with kidney stones without PH of any type. We obtained patient characteristics and diagnostic test results occurring before to less than 6 months after study entrance from a centralized database query and from manual chart review. Differences were examined using standardized differences and multivariable regression., Results: The study sample included 37 patients with PH1 and 147 controls. Patients with PH1 were younger at diagnosis (median age of 3 vs 13.5 years); 75 % of children with PH1 were less than 8 years-old. Patients with PH1 were more likely to have combinations of nephrocalcinosis on ultrasound or CT (43 % vs 3 %), lower eGFR at diagnosis (median = 52 mL/min/1.73 m 2 vs 114 mL/min/1.73 m 2 ), and have normal mobility. Patients with PH1 had higher proportion of calcium oxalate monohydrate kidney stones than controls (median = 100 % vs 10 %). There were no differences in diagnosis of failure to thrive, stone size, or echocardiography results., Conclusions: Children with PH1 are characterized by presentation before adolescence, nephrocalcinosis, decreased eGFR at diagnosis, and calcium oxalate monohydrate stone composition. If externally validated, these characteristics could facilitate earlier diagnosis and treatment of children with PH1., Competing Interests: Disclosures Gregory Tasian is on the Scientific Advisory Board of, is a consultant for, and receives research funding from NovoNordisk and Alnylam Pharmaceuticals. Akanksha Mittal and Nathan Cheng are employed by Alnylam Pharmaceuticals. Alnylam Pharmaceutics funded this study., (Copyright © 2023 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

Introduction: Both Holmium:yttrium-aluminium-garnet (Ho:YAG) laser and Thulium Fiber Laser (TFL) can effectively treat all urinary stone types. This in vitro study evaluated the ablation volume per pulse (AVP) and required energy needed to ablate 1mm 3 (RE, J/mm 3 ) of various stone types at different laser settings with TFL., Methods: 272-µm core-diameter laser fibers (Boston Scientific © ) were connected to a 50 Watts TFL generator (IPG ® ). An experimental setup immerged human stones of calcium oxalate monohydrate (COM), uric acid (UA), and cystine (CYS) with a single pulse lasing emission (0.5/0.8/1 J), in contact mode. Stones were dried out before three-dimensional scanning to measure AVP and deduce from the pulse energy (PE) and AVP the RE. A direct comparison with known Ho:YAG's AVP and RE was then carried out., Results: AVP for COM stones was significantly greater than those for CYS stones and similar to UA stones (p = 0.02 and p = 0.06, respectively). If AVP increased with PE against COM and UA stones, AVP decreased against CYS stones. 1 J PE resulted in a threefold lower RE compared with other PE for COM stones. On the contrary, RE for CYS increased with PE, whereas PE did not had influence on RE for UA. TFL was associated with greater AVP for COM, but lower for UA and CYS stones compared to Ho:YAG laser., Conclusion: This in vitro study firstly describes the ablation volume per pulse and required energy to treat a cubic millimeter of three frequent human stone types, and suggest TFL could not be suited for cystine. Therefore, stone composition could be considered when choosing the laser source for lithotripsy., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: There are conflicting data on the significance of hyperuricemia or hyperuricosuria in urolithiasis formation and on the need for medical treatment., Objectives: To assess the significance of hyperuricemia or hyperuricosuria in urolithiasis formation, particularly when hyperuricemia occurs with normal uricosuria., Methods: The electronic medical records of patients treated in Haifa and the Western Galilee district of Clalit Health Services, Israel, were retrospectively screened for diagnosis of nephrolithiasis or renal or urinary tract/bladder calculi between February 2014 and April 2019. The diagnosis was confirmed by ultrasonography or computed tomography. The study group included patients with one of these diagnoses. Patients in the control group did not have these diagnoses. The inclusion criterion for all patients was the presence of both serum and urinary uric acid levels., Results: The study group included 359 patients and the control group 267. After adjustment by logistic regression, we found no significant differences in the prevalence of hyperuricosuria in the study group (14.8%) compared to the control group (9.7%), odds ratio (OR) 1.54 (95% confidence interval [95%CI] 0.74-3.2, P = 0.245). No significant differences between the groups were observed for hyperuricemia prevalence (45.4% vs. 55.1%, respectively, OR 0.82, 95%CI 0.54-1.25, P = 0.355), nor among those without hyperuricosuria (OR 0.83, 95%CI 0.52-1.33, P = 0.438) and after propensity score matching (OR 0.93, 95%CI 0.66-1.3, P = 0.655)., Conclusions: There were no significant differences in hyperuricemia or hyperuricosuria between the two groups of patients or in hyperuricemia among participants without hyperuricosuria.

Introduction: This study was designed to determine the mineral composition of calculi in nephrocalcinosis with nephrolithiasis, diagnose the underlying disease, and monitor the course of renal function in patients with nephrocalcinosis-nephrolithiasis., Methods: Renal calculi extruded in a series of 8 patients with nephrocalcinosis were analysed using Fourier transmission infrared spectrometry. In 4 patients, next-generation sequencing using a nephrocalcinosis-nephrolithiasis panel was performed to determine the nature of the underlying disease. In addition, longitudinal analysis of renal function was performed in all patients., Results: Seven patients revealed carbonate apatite as the sole constituent of renal calculi. One patient showed a mixed composition of dicalcium phosphate dihydrate/carbonate apatite at first analysis yet in subsequent episodes also had calculi composed of pure carbonate apatite. Further molecular analysis displayed distal renal tubular acidosis in 2 of 4 patients who consented to sequencing. No known genetic defect could be found in the other two cases. In line with prior reports, decline of renal function was dependent on underlying disease. Distal renal tubular acidosis revealed a progressive course of renal failure, whereas other causes showed stable renal function in long term analysis., Conclusion: Nephrocalcinosis with nephrolithiasis is a rare condition with heterogeneous aetiology. Yet mineral composition of renal calculi predominantly consisted of pure carbonate apatite. This uniform finding is similar to subcutaneous calcifications of various origins and might propose a general principle of tissue calcification. Progressive decline of renal function was found in distal renal tubular acidosis, whereas other conditions remained stable over time., (© 2024 The Author(s). Published by S. Karger AG, Basel.)

Introduction: Although ultrasound (US) is the preferred first-line imaging for pediatric nephrolithiasis, CT may be necessary in cases of a nondiagnostic US or when US in not available. Utilization of dose reduction strategies in children undergoing CT for nephrolithiasis is not well described. We compared use of low-dose CT (LDCT) in children presenting to 2 pediatric centers., Methods: We performed a retrospective chart review of children ≤ 17 years of age presenting with suspected nephrolithiasis to 2 tertiary children's hospitals, inclusive of those referred to these centers from nonpediatric facilities between 2013 and 2019. Children were included with an index CT scan from either the pediatric or referring center while those who had prior documented CT for nephrolithiasis within the study period or missing radiation dose assessment were excluded. The primary outcome was LDCT as defined as radiation dose < 3 mGy. The primary comparator was pediatric vs outside referral center. Exploratory analysis evaluated other factors associated with LDCT, including radiation dosage as a continuous variable., Results: A total of 155 individuals met inclusion criteria, with 126 (81.3%) receiving standard dose and 29 (18.7%) receiving LDCT. Pediatric facilities were more likely to utilize LDCT as compared to referral centers ( P < .05). Older age and higher BMI were also found to be associated with increased radiation dose exposure., Conclusions: Pediatric facilities utilized LDCT more frequently, although age and BMI may also influence imaging choices. An understanding of the factors associated with dose reduction in CT will impact future efforts to explore optimum imaging stewardship in pediatric nephrolithiasis.

Mutations in the 24-hydroxylase gene CYP24A1 have been recognized as causes of childhood idiopathic hypercalcemia (IIH), a rare disease (incidence <1:1,000,000 live births) characterized by increased vitamin D sensitivity, with symptomatic severe hypercalcemia. IIH was first described in Great Britain two years after the start of a program of vitamin D supplementation in milk for the prevention of rickets, manifesting in about 200 children with severe hypercalcemia, dehydration, growth failure, weight loss, muscle hypotonia, and nephrocalcinosis. The association between the epidemic occurrence of IIH and vitamin D administration was quickly attributed to intrinsic hypersensitivity to vitamin D, and the pathogenic mechanism was recognized in the inactivation of Cytochrome P450 family 24 subfamily A member 1 (CYP24A1), which was identified as the molecular basis of the pathology. The phenotypic spectrum of CYP24A1 mutation can be variable, manifesting predominantly with childhood onset and severe symptomatology (severe hypercalcemia, growth retardation, lethargy, muscle hypotonia, dehydration), but also with juvenile-adult onset forms with nephrolithiasis, nephrocalcinosis, and alterations in phosphocalcium homeostasis. We describe the case of a patient in whom the diagnosis of IIH was made in adulthood, presenting with finding of nephrocalcinosis in childhood, and with subsequent onset of severe hypercalcemia with hypercalciuria, hypoparathyroidism, hypervitaminosis D, and recurrent renal lithiasis. Genetic investigation revealed the presence in homozygosity of the c&#95;428&#95;430delAAG&#95;p.Glu143del variant in the CYP24A1 gene with autosomal recessive transmission, a mutation not reported in the literature., (Copyright by Società Italiana di Nefrologia SIN, Rome,Italy.)

Drug-induced nephrolithiasis is an important consideration in recurrent stone formers with polypharmacy. While felbamate nephrolithiasis has previously been published in the paediatric population, we present the oldest published case of a felbamate stone in an adult, a man in his 30s with Lennox-Gastaut syndrome. Even with moderate dosing, high drug serum levels can occur. Performing at least one stone analysis remains a critical component to care in these patients. Urologists should have a high index of suspicion for drug stone when stone analysis returns indeterminate characterisation in the absence of infection. Close communication with neurology is key to preventing recurrent stone disease., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: The aim of this study was to evaluate the association between recurrence-free survival (RFS) and perirenal fat thickness (PFT) in a cohort of Chinese population with unilateral nephrolithiasis., Methods: We retrospectively reviewed the medical records of 81 patients with unilateral nephrolithiasis in our center from January 2019 to June 2019. PFT measured on computed tomography (CT) scans was evaluated. Kaplan-Meier curves and log-rank tests were used to assess significant differences in RSF between high-PFT and low-PFT groups within sexes. Univariable and multivariable Cox regression analyses were used to evaluate the potential risk factors for renal stone recurrence., Results: High PFT was significantly associated with high BMI and hyperlipidemia ( p  = .003 and.047, respectively). The PFT of stone-bearing kidney was significantly greater than PFT of non-stone-bearing kidney (0.77 ± 0.60 cm vs. 0.67 ± 0.58 cm, p  = .002) . During the follow-up periods (median 31 months), 21 (25.9%) patients experienced ipsilateral renal stone recurrence. In addition, Kaplan-Meier survival curves showed that patients with low PFT had a significant better RFS than those with high PFT ( p  = .012). In the univariable Cox analyses, male sex and high PFT were significantly associated with a poor RFS ( p  = .042 and .018, respectively). Moreover, both male sex and high PFT retained significance in the multivariable analyses ( p  = .045 and .020, respectively)., Conclusions: Our findings suggested that PFT is a noninvasive and feasible parameter, which may help in the risk stratification of renal stone recurrence in the follow-up periods.

Background and Objectives: Dent's disease type 1 (DD1) is a rare X-linked hereditary pathology caused by CLCN5 mutations that is characterized mainly by proximal tubule dysfunction, hypercalciuria, nephrolithiasis/nephrocalcinosis, progressive chronic kidney disease, and low-weight proteinuria, the molecular hallmark of the disease. Currently, there is no specific curative treatment, only symptomatic and does not prevent the progression of the disease. In this study we have isolated and characterized urinary extracellular vesicles (uEVs) enriched in exosomes that will allow us to identify biomarkers associated with DD1 progression and a better understanding of the pathophysiological bases of the disease., Materials and Methods: Through a national call from the Spanish Society of Nephrology (SEN) and the Spanish Society of Pediatric Nephrology (AENP), urine samples were obtained from patients and controls from different Spanish hospitals, which were processed to obtain the uEVS. The data of these patients were provided by the respective nephrologists and/or extracted from the RENALTUBE registry. The uEVs were isolated by ultracentrifugation, morphologically characterized and their protein and microRNA content extracted., Results: 25 patients and 10 controls were recruited, from which the urine was processed to isolate the uEVs. Our results showed that the relative concentration of uEVs/mL is lower in patients compared to controls (0.26 × 10 6 uEVs/mL vs 1.19 × 10 6 uEVs/mL, p < 0.01). In addition, the uEVs of the patients were found to be significantly larger than those of the control subjects (mean diameter: 187.8 nm vs 143.6 nm, p < 0.01). Finally, our data demonstrated that RNA had been correctly extracted from both patient and control exosomes., Conclusions: In this work we describe the isolation and characterization of uEVs from patients with Dent 1 disease and healthy controls, that shall be useful for the subsequent study of differentially expressed cargo molecules in this pathology., (Copyright © 2023 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.)

Background: The novel pulsed thulium:yttrium-aluminum-garnet (p-Tm:YAG) laser was recently introduced. Current studies present promising p-Tm:YAG ablation efficiency, although all are based on non-human stone models or with unknown stone composition. The present study aimed to evaluate p-Tm:YAG ablation efficiency for stone dust from human urinary stones of known compositions., Methods: Calcium oxalate monohydrate (COM) and uric acid (UA) stones were subjected to lithotripsy in vitro using a p-Tm:YAG laser generator (Thulio®, Dornier MedTech GmbH, Germany). 200 J was applied at 0.1 J × 100 Hz, 0.4 J × 25 Hz or 2.0 J × 5 Hz (average 10W). Ablated stone dust mass was calculated from weight difference between pre-lithotripsy stone and post-lithotripsy fragments > 250 µm. Estimated ablated volume was calculated using prior known stone densities (COM: 2.04 mg/mm 3 , UA: 1.55 mg/mm 3 )., Results: Mean ablation mass efficiency was 0.04, 0.06, 0.07 mg/J (COM) and 0.04, 0.05, 0.06 mg/J (UA) for each laser setting, respectively. This translated to 0.021, 0.029, 0.034 mm 3 /J (COM) and 0.026, 0.030, 0.039 mm 3 /J (UA). Mean energy consumption was 26, 18, 17 J/mg (COM) and 32, 23, 17 J/mg (UA). This translated to 53, 37, 34 J/mm 3 (COM) and 50, 36, 26 J/mm 3 (UA). There were no statistically significant differences for laser settings or stone types (all p > 0.05)., Conclusion: To our knowledge, this is the first study showing ablation efficiency of the p-Tm:YAG laser for stone dust from human urinary stones of known compositions. The p-Tm:YAG seems to ablate COM and UA equally well, with no statistically significant differences between differing laser settings., (© 2023. The Author(s).)

The incidence of stone disease has increased significantly in the past 30 years, with a reported prevalence of 11% of the U.S. population in 2022, up from 9% in 2012 and 5.2% in 1994.1 While prevention is a vital aspect of management, many patients present with symptomatic urolithiasis requiring surgical management. Emerging advances in endoscopy and technology has led to a dynamic shift in the surgical management of stone disease. This paper will serve as a comprehensive review to inform urologic and non-urologic medical professionals alike, as well as the layperson, on the surgical treatment of nephrolithiasis, starting from the initial evaluation, laboratory and radiographic studies, and various surgical options. Additionally, the nuances of managing the pediatric and pregnant patient with nephrolithiasis will be explored. Using the most up-to-date urologic data, our aim is to provide a comprehensive resource for readers who interact with patients experiencing acute episodes of urolithiasis.

Nephrolithiasis is highly prevalent and brings health and economic burdens to patients. The augmentation of nephrolithiasis may be associated with exposure to phthalate metabolites. However, few studies investigated the effect of various phthalates exposure on nephrolithiasis. We analyzed data from 7139 participants aged 20 years or above from the National Health and Nutrition Examination Survey (NHANES) 2007-2018. Serum calcium level-stratified univariate and multivariate linear regression analyses were performed to explore the relationship between urinary phthalate metabolites and nephrolithiasis. As a result, the prevalence of nephrolithiasis was approximately 9.96%. After adjusting for confounding factors, associations were found between serum calcium concentration with monoethyl phthalate (P = 0.012) and mono-isobutyl phthalate (P = 0.003) compared with tertile 1 (T1). In adjusted analysis, nephrolithiasis was positively associated with middle and high tertiles of mono benzyl phthalate (P < 0.05) compare with low tertile group. Furthermore, high-level exposure to mono-isobutyl phthalate had a similar positive association with nephrolithiasis (P = 0.028). Our findings provide evidence that exposure to certain phthalate metabolites (i.e. MiBP and MBzP) may be associated with a high risk of nephrolithiasis depending on serum calcium level., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Aim: The levels of serum phosphorus (P) are low or low-normal in primary hyperparathyroidism (PHPT), and there is an inverse relationship between the levels of parathormone (PTH) and P. However, when considering the diagnostic and surgical indication criteria of PHPT, serum P levels are generally ignored. The aim of this study was to retrospectively evaluate the association of serum P levels with the clinical outcomes of PHPT., Materials and Methods: A retrospective evaluation was made of the data of 424 consecutive patients (370 females, 54 males) with PHPT who presented at our centre., Results: The mean age of the study population was 57 ± 11.68 years. The mean P was 2.57 ± 0.53 mg/dl. Asymptomatic disease was determined in 199 (47%) patients. Male patients had significantly lower levels of P. Symptomatic patients and patients with renal stones, vitamin D < 20 µg/l, calcium level ≥ 11.2 mg/dl, 24 h urinary calcium > 400 mg/day, or hypomagnesemia, were seen to have significantly lower levels of P (p < 0.05). Hypophosphatemia (hypoP) was found in 202 of 424 patients (47%), and these patients had a higher rate of symptomatic disease (63% to 44%, p < .0001). Of the 61 (88%) patients with moderate hypoP, 54 (88%) had at least one of the surgical criteria. A statistically significant increase in the incidence of hypoP was determined in symptomatic and male patients. In the patients with hypoP, serum PTH and urine calcium levels were found to be higher, and lumbar T-scores and serum vitamin D levels were lower. The patients with hypoP had higher rates of renal stones and osteoporosis (p < 0.05)., Conclusions: The current study results show that hypoP is associated with a higher risk of osteoporosis and renal stones in PHPT patients. Even if patients are asymptomatic, moderate hypoP may be associated with poor outcomes of PHPT. Therefore, moderate hypoP may be a new criterion for parathyroidectomy, regardless of hypercalcemia level., (© 2023. The Author(s), under exclusive licence to Italian Society of Endocrinology (SIE).)

Nephrolithiasis is a common and frequently-occurring disease in the urinary system with high recurrence. The present study aimed to explore the protective effect and underlying mechanism of hydroxycitric acid (HCA) in hyperoxaluria-induced nephrolithiasis in vitro and in vivo . Crystal deposition and pathophysiological injury in rat models of glyoxylate-induced nephrolithiasis were examined using H&E staining. Cell models of nephrolithiasis were established by oxalate-treated renal tubular epithelial cells. The levels of oxidative stress indexes were determined by ELISA kits. Cell proliferation in vivo and in vitro was evaluated using a cell counting kit-8 (CCK-8) assay and Ki-67 cell proliferation detection kit. Cell apoptosis was measured by flow cytometry and TUNEL staining. The protein levels were examined by western blotting. Our results showed that HCA administration significantly reduced crystal deposition and kidney injury induced by glyoxylate. HCA also alleviated oxidative stress via upregulating the antioxidant enzyme activities of superoxide dismutase (SOD) and catalase (CAT) and reducing the malondialdehyde (MDA) content. Moreover, HCA treatment promoted cell proliferation and inhibited apoptosis of renal tubular epithelial cells exposed to hyperoxaluria. Of note, Nrf2 activator dimethyl fumarate (DMF) exerted the same beneficial effects as HCA in nephrolithiasis. Mechanistically, HCA prevented crystal deposition and oxidative stress induced by hyperoxaluria through targeting the Nrf2/Keap1 antioxidant defense pathway, while knockdown of Nrf2 significantly abrogated these effects. Taken together, HCA exhibited antioxidation and anti-apoptosis activities in nephrolithiasis induced by hyperoxaluria via activating Nrf2/Keap1 pathway, suggesting that it may be an effective therapeutic agent for the prevention and treatment of nephrolithiasis.

Oxalate is a metabolic end-product whose systemic concentrations are highly variable among individuals. Genetic (primary hyperoxaluria) and non-genetic (e.g., diet, microbiota, renal and metabolic disease) reasons underlie elevated plasma concentrations and tissue accumulation of oxalate, which is toxic to the body. A classic example is the triad of primary hyperoxaluria, nephrolithiasis, and kidney injury. Lessons learned from this example suggest further investigation of other putative factors associated with oxalate dysmetabolism, namely the identification of precursors (glyoxylate, aromatic amino acids, glyoxal and vitamin C), the regulation of the endogenous pathways that produce oxalate, or the microbiota's contribution to oxalate systemic availability. The association between secondary nephrolithiasis and cardiovascular and metabolic diseases (hypertension, type 2 diabetes, and obesity) inspired the authors to perform this comprehensive review about oxalate dysmetabolism and its relation to cardiometabolic toxicity. This perspective may offer something substantial that helps advance understanding of effective management and draws attention to the novel class of treatments available in clinical practice.

Background: Existing evidence shows that there is an independent correlation between nephrolithiasis and gout, and hyperuricemia is the most important risk factor for gout. However, hyperuricemia was often used as an accompanying symptom of gout to explore its association with nephrolithiasis, there were few studies to explore whether hyperuricemia itself or serum uric acid (SUA) is related to the risk of nephrolithiasis. Evidence on the relationship between hyperuricemia and nephrolithiasis is still insufficient., Methods: A total of 22,303 participants aged 30 to 79 years who participated in the China Multi-Ethnic Cohort (CMEC) study in Yunnan Province from May 2018 to September 2019 were included in the study. All participants received standardized face-to-face interviews, medical examinations, and biochemical examinations. Logistic regression was used to estimate the association between hyperuricemia and nephrolithiasis, and a restricted cubic spline (RCS) model was used to explore the dose-response relationship between SUA and the risk of nephrolithiasis., Results: 14.5% of all participants were diagnosed with hyperuricemia, and 12.1% were diagnosed with nephrolithiasis. After adjusting for all potential confounders, the OR (95%CI) for nephrolithiasis in participants with hyperuricemia compared with participants without hyperuricemia was 1.464 (1.312,1.633), p < 0.001. Restricted cubic spline regression analysis showed that the risk of nephrolithiasis increased with the increase of SUA, and when the level of SUA is higher than 356 μmol/L in males and higher than 265 μmol/L in females, there is a dose-response relationship between the increase of SUA and the risk of nephrolithiasis in both males and females (p for nonlinearity = 0.1668, p for nonlinearity = 0.0667)., Conclusion: Asymptomatic hyperuricemia is associated with an increased risk of developing nephrolithiasis. Before reaching the diagnostic criteria for hyperuricemia, the risk of nephrolithiasis rises with the increase in SUA. This suggests that controlling SUA levels may be significant for the prevention of nephrolithiasis., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Purpose of Review: The prevalence of uric acid (UA) urolithiasis contributes significantly to global disease burden, due to high rates of recurrence and diagnostic challenges. Dissolution therapy plays a valuable role in the conservative management of UA calculi, reducing the requirement for surgical intervention. This review summarises the existing evidence for the efficacy of medical dissolution of uric acid urolithiasis., Recent Findings: A systematic search was conducted of worldwide literature according to PRISMA methodology and Cochrane standards for systematic review. Studies were included if they reported outcome data for the administration of medical therapy for the dissolution of UA calculi. A total of 1075 patients were included in the systematic review. Complete or partial dissolution of UA calculi was observed in 80.5% of patients (865/1075 patients), with 61.7% (647/1048 patients) achieving complete dissolution and 19.8% (207/1048 patients) achieving partial dissolution. A discontinuation rate of 10.2% (110/1075 patients) was noted, and 15.7% (169/1075 patients) required surgical intervention. Dissolution therapy is a safe and effective method of conservatively managing uric acid stones in the short term. Despite the significant disease burden of UA calculi, current guidelines are limited by deficiencies in the existing body of research. Further research should be undertaken to develop evidence-based clinical guidelines for diagnosis, treatment, and prevention of UA urolithiasis., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Kidney diseases with genetic etiology in children present with an overlapping spectrum of manifestations. We aimed to analyze the clinical utility of genetic testing in the diagnosis and management of suspected genetic kidney diseases in children., Methods: In this retrospective study, children ≤ 18 years in whom a genetic test was ordered were included. Clinical indications for genetic testing were categorized as Glomerular diseases, nephrolithiasis and/or nephrocalcinoses, tubulopathies, cystic kidney diseases, congenital abnormality of kidney and urinary tract, chronic kidney disease of unknown aetiology and others. Clinical exome sequencing was the test of choice. Other genetic tests ordered were sanger sequencing, gene panel, multiplex ligation-dependent probe amplification and karyotyping. The pathogenicity of the genetic variant was interpreted as per the American College of Medical Genetics classification., Results: A total of 86 samples were sent for genetic testing from 76 index children, 8 parents and 2 fetuses. A total of 74 variants were reported in 47 genes. Out of 74 variants, 42 were missense, 9 nonsense, 12 frameshifts, 1 indel, 5 affected the splicing regions and 5 were copy number variants. Thirty-two were homozygous, 36 heterozygous and 6 were hemizygous variants. Twenty-four children (31.6%) had pathogenic and 11 (14.5%) had likely pathogenic variants. Twenty-four children (31.6%) had variants of uncertain significance. No variants were reported in 17 children (22.3%). A genetic diagnosis was made in 35 children with an overall yield of 46%. The diagnostic yield was 29.4% for glomerular diseases, 53.8% for tubular disorders, 81% for nephrolithiasis and/or nephrocalcinoses, 60% for cystic kidney diseases and 50% for chronic kidney disease of unknown etiology. Genetic testing made a new diagnosis or changed the diagnosis in 15 children (19.7%)., Conclusion: Nearly half (46%) of the children tested for a genetic disease had a genetic diagnosis. Genetic testing confirmed the clinical diagnoses, changed the clinical diagnoses or made a new diagnosis which helped in personalized management., (© 2023. The Author(s).)

Objective: To investigate the relationship between plasma levels of sKL and Nrf2 and calcium oxalate calculi., Methods: The clinical data of 135 patients with calcium oxalate calculi treated in the Department of Urology of the second affiliated Hospital of Xinjiang Medical University from February 2019 to December 2022, and 125 healthy persons who underwent physical examination in the same period were collected and divided into healthy group and stone group. The levels of sKL and Nrf2 were measured by ELISA. Correlation test was used to analyze the risk factors of calcium oxalate stones, logistic regression analysis was used to analyze the risk factors of calcium oxalate stones, and ROC curve was used to evaluate the sensitivity and specificity of sKL and Nrf2 in predicting urinary calculi., Results: Compared with the healthy group, the plasma sKL level in the stone group decreased (111.53 ± 27.89 vs 130.68 ± 32.51), while the plasma Nrf2 level increased (300.74 ± 114.31 vs 246.74 ± 108.22). There was no significant difference in the distribution of age and sex between the healthy group and the stone group, but there were significant differences in plasma levels of WBC, NEUT, CRP, BUN, BUA, SCr, BMI, and eating habits. The results of correlation test showed that the level of plasma Nrf2 was positively correlated with SCr (r = 0.181, P < 0.05) and NEUT (r = 0.144 P < 0.05). Plasma sKL was not significantly correlated with Nrf2 (r = 0.047, P > 0.05), WBC (r = 0.108, P > 0.05), CRP (r = - 0.022, P > 0.05), BUN (r = - 0.115, P > 0.05), BUA (r = - 0.139, P > 0.05), SCr (r = 0.049, P > 0.05), and NEUT (r = 0.027, P > 0.05). Plasma Nrf2 was not significantly correlated with WBC (r = 0.097, P > 0.05), CRP (r = 0.045, P > 0.05), BUN (r = 0.122, P > 0.05), and BUA (r = 0.122, P > 0.05); (r = 0.078, P > 0.05) had no significant correlation. Logistic regression showed that elevated plasma sKL (OR 0.978, 95% CI 0.969 ~ 0.988, P < 0.05) was a protective factor for the occurrence of calcium oxalate stones, BMI (OR 1.122, 95% CI 1.045 ~ 1.206, P < 0.05), dietary habit score (OR 1.571, 95% CI 1.221 ~ 2.020, P < 0.05), and WBC (OR 1.551, 95% CI 1.423 ~ 1.424, P < 0.05). Increased NEUT (OR 1.539, 95% CI 1.391 ~ 1.395, P < 0.05) and CRP (OR 1.118, 95% CI: 1.066 ~ 1.098, P < 0.05) are risk factors for the occurrence of calcium oxalate stones., Conclusion: Plasma sKL level decreased and Nrf2 level increased in patients with calcium oxalate calculi. Plasma sKL may play an antioxidant role in the pathogenesis of calcium oxalate stones through Nrf2 antioxidant pathway., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Uric acid lithiasis accounts for about 10% of all types of renal lithiasis. The most common causes of uric acid lithiasis are low urinary pH, followed by high concentration of urinary uric acid, and low diuresis. Treatment of patients consists of alkalinization of urine, reducing the consumption of purine-rich foods, and administration of xanthine oxidase inhibitors, because there are no established therapeutic inhibitors of uric acid crystallization. We recently found that theobromine inhibited uric acid crystallization in vitro, and that the increased urinary level of theobromine following its oral consumption was associated with the prevention of uric acid crystallization. In this study, we evaluated the inhibitory effects of theobromine metabolites and other methylxanthine-related compounds on uric acid crystallization. We also measured the urinary concentrations of theobromine and its metabolites in samples from healthy individuals and patients with uric acid stones and compared the extent of uric acid supersaturation and uric acid crystal formation in these different samples. Theobromine and other methylxanthines that lacked a substituent at position 1 inhibited uric acid crystallization, but other methylxanthines did not have this effect. Individuals with clinical parameters that favored uric acid crystallization did not develop uric acid crystals when theobromine and its metabolites were in the urine at high levels. Thus, theobromine and its metabolites reduced the risk of uric acid lithiasis.

Background: Idiopathic Calcitriol Induced Hypercalcemia is a rare cause of a common condition of hypercalcemia. Hypercalcemia is most commonly the result of hyperparathyroidism and together with hypercalcemia of malignancy accounts for over 95% of cases. Idiopathic Calcitriol Induced Hypercalcemia can mimic hypercalcemia secondary to granulomatous diseases like sarcoidosis, but with apparent absences of both imaging and physical exam findings consistent with the disease. We report here a 51-year-old man who presented with recurrent nephrolithiasis, hypercalcemia, and acute kidney injury., Case Presentation: A 51-year-old man presented with severe back pain and mild hematuria. He had a history of recurrent nephrolithiasis over the course of a 15-year period. On presentation his calcium was elevated at 13.4 mg/dL, creatinine was 3.1 mg/dL (from baseline of 1.2), and his PTH was reduced at 5 pg/mL. CT abdomen and pelvis showed acute nephrolithiasis which was managed medically. Work up for the hypercalcemia included an SPEP which was normal, Vit D,1,25 (OH)2 was elevated at 80.4 pg/mL, CT chest showed no evidence of sarcoidosis. Management with 10 mg prednisone showed marked improvement in the hypercalcemia and he no longer had any symptoms of hypercalcemia., Conclusion: Idiopathic Calcitriol Induced Hypercalcemia is a rare cause of hypercalcemia. All reported cases benefit from more intensive long-term immunosuppression. This report helps consolidate the diagnosis of Idiopathic Calcitriol Induced Hypercalcemia and encourages researchers to better investigate its underlying pathogenesis., (© 2023. The Author(s).)

Purpose: To evaluate whether symptomatic recurrent nephrolithiasis leads to loss of kidney function., Methods: Adults who presented to the Emergency Department at least twice with symptomatic and radiologically confirmed nephrolithiasis were retrospectively recruited. Primary endpoint was the change in glomerular filtration rate (GFR) between baseline and at the time of data collection. Secondary endpoints include GFR slope defined as the mean rate of change in GFR from baseline to the end of the study period., Results: 240 patients had recurrent symptomatic nephrolithiasis. Median follow-up was 5.4 years. The median age of first acute presentation was 51.6 years and the median baseline serum creatinine (bsCr) was 85.5 umol/l. 17.5% (n = 42) had worsening GFR, with the average change in GFR of - 8.64 ml/min/1.73 m 2 per year. Four patients progressed to ESKD requiring haemodialysis. 14.5% (n = 35) had calcium oxalate stones. Univariate analysis showed older patients (p < 0.001), more symptomatic stone episodes (p < 0.001) and non-calcium-containing stones (p < 0.001) were strongly associated with deteriorating kidney function. Age (p = 0.002) and number of acute stone episodes (p = 0.011) were significant predictive factors when unadjusted to co-morbidities. Age (p = 0.018) was the only predictive factor of worsening GFR when adjusted for co-morbidities. Average mean GFR slope was - 2.83/min/1.73 m 2 per year., Conclusions: Recurrent symptomatic nephrolithiasis is associated with loss of kidney function, in older patients, increased episodes of symptomatic nephrolithiasis and non-calcium-containing stones. Age is the only predictive factor for progression to chronic kidney disease in this subgroup., (© 2023. The Author(s).)

Background: Accurately identifying uric acid stones is pivotal in determining the appropriate treatment strategy for patients. This study aimed to design an innovative nomogram to predict the occurrence of uric acid stones in the upper urinary tract., Methods: This retrospective study examined 680 patients with urinary stones from October 2019 to September 2022. Risk factors were identified through univariate and multivariate logistic regression, leading to the development of a nomogram. This model's validity was then assessed internally using receiver operating characteristic (ROC) curves, the area under the curve (AUC), calibration curves, and decision curve analysis (DCA)., Results: Our findings revealed that metabolic syndrome (odds ratio (OR) = 4.347, 95% confidence interval (CI) 1.306-14.466, p = 0.017), serum urea levels (OR = 1.004, 95% CI 1.143-2.002, p = 0.004), urinary pH (OR = 0.185, 95% CI 0.059-0.583, p = 0.004), urinary potassium (OR = 0.926, 95% CI 0.875-0.981, p = 0.009), and urinary calcium (OR = 0.693, 95% CI 0.492-0.977, p = 0.037) are independent factors for upper urinary tract uric acid stones. Utilizing the five variables, we developed a predictive nomogram. The AUC of the training cohort and the validation cohort were 0.917 (95% CI 0.871-0.963) and 0.914 (95% CI 0.850-0.978), respectively. Calibration curves indicated strong consistency in both cohorts, and the DCA revealed the model's clinical utility., Conclusions: We devised a reliable and user-friendly nomogram to predict uric acid stones in the upper urinary tract. It is based on metabolic syndrome, serum biochemical markers, and 24-hour urinary parameters. Key determinants include metabolic syndrome, serum urea, urinary pH, urinary potassium and urinary calcium., Competing Interests: The authors declare no conflict of interest., (© 2023 The Author(s).)

Purpose: Growing evidence have suggested an association between nephrolithiasis and cardiovascular disease (CVD) with unclear mechanism. Oxidized low-density lipoproteins (oxLDL) induces atherosclerosis and was found to be the possible link between these two diseases. Our study aimed to examine the serum, urine and kidney expression of oxLDL in relation to large calcium oxalate (CaOx) renal stone disease., Methods: A total of 67 large CaOx dominant renal stone patients and 31 stone-free controls were enrolled in the prospective case-control study. All participants were without known CVD history. Serum, urine, and kidney biopsy were collected before and during percutaneous nephrolithotomy, respectively. Enzyme-linked immunosorbent assays were used to assess serum and urine oxLDL, lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), and high-sensitivity C-reactive protein (hsCRP)., Results: There was no significantly difference in circulating oxLDL, but serum hsCRP was significantly near two-fold higher in nephrolithiasis patients. Serum hsCRP was also correlated with stone maximal length. Urine oxLDL was significantly higher in the nephrolithiasis group and correlated with serum hsCRP and stone maximal length. Increased oxLDL uptake in kidney was found in nephrolithiasis patients, whereas no significantly renal expression of oxLDL was observed in controls., Conclusions: The renal uptake of oxLDL with increased oxLDL excretion from large CaOx renal stone formers, independent of increased circulating oxLDL, is a novel pathological finding in kidney stone disease and brings attention to the possible involvement of renal steatosis in the process of urolithiasis formation., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)