High Self-Reported Prevalence of Kidney Stones in Trinidad and Tobago: Results of a Cross-Sectional Online Survey.

Introduction No data exist on the prevalence of kidney stone disease in Trinidad and Tobago. Local clinicians have noted that the disease is very common, and this study represents the first attempt to investigate the prevalence of urolithiasis in these islands. Objectives The objective is to estimate the prevalence of kidney stone disease in Trinidad and Tobago and to investigate the epidemiology of the disease. Methods An online survey using the online tool Survey Monkey was distributed among members of the public via instant messaging and social media. The survey captured data relating to the stone status and demographics of respondents. Results 1225 patients completed the survey of whom 46.5% were males and 53.5% were females. Respondents were equally distributed throughout the country. 16.74% of those surveyed indicated that they were currently affected by stones confirmed by imaging. Kidney stones were more common among Trinidadians of East Indian ancestry (20.6% vs 10.6%). Positive correlations were established between kidney stones and the presence of hypertension, diabetes, and gout. Persons with kidney stones were more likely to have a family member with the disease - 45.6% vs 31.4% among those without kidney stones. Conclusion This study demonstrates a high self-reported prevalence of kidney stones in Trinidad and Tobago.

Proton pump inhibitors use is associated with a higher prevalence of kidney stones: NHANES 2007-2018.

BACKGROUND: Proton pump inhibitors (PPIs) are widely used throughout the world as an effective gastrointestinal drug. Nevertheless, according to the existing literature, PPIs can reduce the excretion of magnesium, calcium and other components in urine, which may promote the formation of kidney stones. We used the National Health and Nutrition Examination Survey (NHANES) database to further investigate the association between the use of PPIs and the prevalence of kidney stones. METHODS: We performed a cross-sectional analysis using data from 2007 to 2018 NHANES. PPIs use information of 29,910 participants was obtained by using prescription medications in the preceding month, and kidney stones were presented by a standard questionnaire. Multiple regression analysis and stratified analysis were used to estimate the association between PPIs use and kidney stones after an adjustment for potential confounders. RESULTS: The multiple logistic regression indicated that the PPIs exposure group (P1) had a significantly higher risk of nephrolithiasis than the PPIs non-exposure group (P0) in Model 3 (OR 1.24, 95% CI 1.10-1.39, P < 0.001). The stratified analyses indicated there were significant statistical differences between PPIs use and kidney stones among females (OR 1.36, 95% CI 1.15-1.62, P < 0.001), non-Hispanic whites (OR 1.27, 95% CI 1.09-1.48, P = 0.002), individuals with an education level than 11th grade (OR 1.41, 95% CI 1.13-1.76, P = 0.002) and individuals with an annual family income of $0 to $19,999 (OR 1.32, 95% CI 1.06-1.65, P = 0.014) and $20,000 to $44,999 (OR 1.25, 95% CI 1.02-1.54, P = 0.033) in Model 3. CONCLUSIONS: Our study revealed that PPIs use is associated with a higher prevalence of kidney stones for the US population, primarily among women, non-Hispanic whites, individuals with low education levels and individuals with low household income levels. Further studies are required to confirm our findings.

What is the definition of stone dust and how does it compare with clinically insignificant residual fragments? A comprehensive review.

PURPOSE: During endoscopic stone surgery, Holmium:YAG (Ho:YAG) and Thulium Fiber Laser (TFL) technologies allow to pulverize urinary stones into fine particles, ie DUST. Yet, currently there is no consensus on the exact definition of DUST. This review aimed to define stone DUST and Clinically Insignificant Residual Fragments (CIRF). METHODS: Embase, MEDLINE (PubMed) and Cochrane databases were searched for both in vitro and in vivo articles relating to DUST and CIRF definitions, in November 2023, using keyword combinations: "dust", "stones", "urinary calculi", "urolithiasis", "residual fragments", "dusting", "fragments", "lasers" and "clinical insignificant residual fragments". RESULTS: DUST relates to the fine pulverization of urinary stones, defined in vitro as particles spontaneously floating with a sedimentation duration ≥ 2 sec and suited for aspiration through a 3.6Fr-working channel (WC) of a flexible ureteroscope (FURS). Generally, an upper size limit of 250 µm seems to agree with the definition of DUST. Ho:YAG with and without "Moses Technology", TFL and the recent pulsed-Thulium:YAG (pTm:YAG) can produce DUST, but no perioperative technology can currently measure DUST size. The TFL and pTm:YAG achieve better dusting compared to Ho:YAG. CIRF relates to residual fragments (RF) that are not associated with imminent stone-related events: loin pain, acute renal colic, medical or interventional retreatment. CIRF size definition has decreased from older studies based on Shock Wave Lithotripsy (SWL) (≤ 4 mm) to more recent studies based on FURS (≤ 2 mm) and Percutaneous Nephrolithotomy(PCNL) (≤ 4 mm). RF ≤ 2 mm are associated with lower stone recurrence, regrowth and clinical events rates. While CIRF should be evaluated postoperatively using Non-Contrast Computed Tomography(NCCT), there is no consensus on the best diagnostic modality to assess the presence and quantity of DUST. CONCLUSION: DUST and CIRF refer to independent entities. DUST is defined in vitro by a stone particle size criteria of 250 µm, translating clinically as particles able to be fully aspirated through a 3.6Fr-WC without blockage. CIRF relates to ≤ 2 RF on postoperative NCCT.

Metabolic Syndrome and the Risk of Kidney Stones: a Large-scale Cohort Study from 487,860 UK Biobank participants.

OBJECTIVE: While some studies have suggested an association between metabolic syndrome and kidney stones, the quality and level of evidence in these studies vary. Whether some individual characteristics and clustering of metabolic syndrome traits increase the risk of kidney stones has not been examined in a large-scale prospective cohort. MATERIALS: We conducted a retrospective analysis of data from a prospective cohort of 487,860 UK Biobank participants who were free from kidney stones at baseline. The presence of metabolic syndrome was based on five criteria: abdominal obesity, high triglyceride levels, low high-density lipoprotein (HDL) cholesterol levels, high blood pressure (HBP), and type 2 diabetes mellitus (T2DM). Cox proportional hazards regression models were used to evaluate the association between metabolic syndrome and risk of kidney stones. RESULTS: After an average follow-up period of 12.6 years, a total of 5,213 of the 487,860 participants included in the UK Biobank study developed kidney stones. The partial traits of metabolic syndrome, including waist circumference (HR: 1.15, 95% CI: 1.10-1.20), HDL cholesterol (0.66, 0.55-0.79), HBP (1.11, 1.03-1.19) and T2DM (1.14, 1.04-1.21), were independently associated with the occurrence of kidney stones. The clustering of metabolic syndrome is significantly associated with kidney stone formation, and as the number of metabolic syndrome traits increases, the risk of kidney stones gradually increases. CONCLUSION: Metabolic syndrome is a significant and independent risk factor for the development of kidney stones. This association suggests that kidney stones may represent a systemic disorder influenced by the interplay of various metabolic risk factors.

A novel technique of percutaneous transhepatic treatment of biliary-enteric anastomotic occlusive strictures with compliant balloon-occluded distal cholangiography and large-bore catheter: a retrospective case series.

Background: Endoscopic retrograde cholangiopancreatography (ERCP) or percutaneous transhepatic biliary balloon dilatation (PTBD) is a challenge in resolving biliary-enteric anastomotic occlusive strictures (BEAOS) and/or coexisting stones. The biliary-enteric anastomosis (BEA) often cannot be seen because of the surgically altered gastrointestinal anatomy. Here, a technique that combined percutaneous compliant-occluded distal cholangiography and the maintenance of a large-bore catheter is described to resolve this issue. Methods: A retrospective review of 10 patients who presented with BEAOS with/without coexisting stones who were treated with percutaneous compliant balloon-occluded distal cholangiography, bile duct stone removal, and the maintenance of a large-bore catheter between February 2017 and January 2021 was performed. Treatment response, laboratory examinations, including hepatic function tests, routine blood tests, and blood electrolytes, complications, and imaging data were evaluated. Paired t-tests were used to investigate the difference of laboratory examinations before and after the procedure. Results: All 10 cases were technically successful. A total of 9 stones in 6 patients were successfully removed by the compliant balloon. All catheters were removed after the patency of the stricture was confirmed by percutaneous transhepatic cholangiography (PTHC) 6 months later. No severe adverse events occurred during the perioperative period. There were 2 patients who experienced episodes of cholangitis during the follow-up period (mean, 17 months; range, 4-24 months), and neither BEAOS nor bile duct stones recurred within 2 years after the procedure. White blood cells (WBC), total bilirubin (TB), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were (6.0±1.4)×109/L and (6.0±1.6)×109/L (P=0.91), 31.4±15.7 and 29.6±10.3 µmol/L (P=0.74), 50.8±20.0 and 85.8±67.0 U/L (P=0.16), and 42.6±15.2 and 71.8±44.9 U/L (P=0.09) pre and postintervention, respectively. Conclusions: Percutaneous transhepatic compliant balloon-occluded distal cholangiography and the maintenance of a large-bore catheter probably provide an effective and safe alternative method for resolving BEAOS and/or coexisting stones.

Clinical efficacy and short-term outcome of combining flexible cystoscopy with percutaneous nephrolithotomy for complex renal stone management.

OBJECTIVE: This study aims to evaluate the clinical efficacy and short-term prognosis of using flexible cystoscopy with percutaneous nephrolithotomy to treat complex renal stones. METHODS: A retrospective analysis was conducted on patients with complex kidney stones treated at Gansu Provincial Hospital of TCM and Lanzhou City No. 2 People's Hospital from July 2019 to July 2022. The study divided the patients into a control group (n=95), who underwent percutaneous nephrolithotomy alone, and an observation group (n=109), who received additional holmium laser lithotripsy and cystoscopy. We compared stone clearance rates at 5 days and 1 month post-surgery, analyzed patient prognosis over a year based on stone recurrence, and assessed risk factors through logistic regression. Perioperative data, changes in renal function indiex 3 days post-surgery, and complication rates were also evaluated. RESULTS: The observation group exhibited a significantly higher stone clearance rate at 5 days post-surgery (P=0.002) compared to the control group, although no significant difference was observed at 1 month (P=0.823). The operative time was significantly shorter (P<0.001), and postoperative levels of BUA, Cys-c, and ß2-BMG were lower (P<0.05) in the observation group. Additionally, treatment regimen, BMI, and STONE score were influencing factors for stone recurrence within 1 year. CONCLUSION: Flexible cystoscopy combined with percutaneous nephrolithotomy offers superior short-term outcomes in the treatment of complex renal stones, including enhanced stone clearance, reduced operative time, and minimized renal function impairment shortly after surgery. Moreover, treatment approach, BMI, and STONE score play pivotal roles in predicting stone recurrence.

Accurate and safe diagnosis and treatment of neoplastic biliary lesions using a novel 9F and 11F digital single-operator cholangioscope.

Background and study aims Digital single-operator cholangioscopy (DSOC) allows the diagnosis of biliary duct disorders and treatment for complicated stones. However, these technologies have limitations such as the size of the probe and working channel, excessive cost, and low image resolution. Recently, a novel DSOC system (eyeMAX, Micro-Tech, Nanjing, China) was developed to address these limitations. We aimed to evaluate the usefulness and safety of a novel 9F and 11F DSOC system in terms of neoplastic diagnostic accuracy based on visual examination, ability to evaluate tumor extension and to achieve complete biliary stone clearance, and procedure-related adverse events (AEs). Patients and methods Data from ≥ 18-year-old patients who underwent DSOC from July 2021 to April 2022 were retrospectively recovered and divided into a diagnostic and a therapeutic cohort. Results A total of 80 patients were included. In the diagnostic cohort (n = 49/80), neovascularity was identified in 26 of 49 patients (46.9%). Biopsy was performed in 65.3% patients with adequate tissue sample obtained in 96.8% of cases. Biopsy confirmed neoplasia in 23 of 32 cases. DSOC visual impression achieved 91.6% sensitivity and 87.5% specificity in diagnosing neoplasms. In the therapeutic cohort (n = 43/80), 26 of 43 patients required lithotripsy alone. Total stone removal was achieved in 71% patients in the first session. Neither early nor late AEs were documented in either the diagnostic or therapeutic cohort. Conclusions The novel DSOC device has excellent diagnostic accuracy in distinguishing neoplastic biliary lesions as well as therapeutic benefits in the context of total stone removal, with no documented AEs.

Tartronic Acid as a Potential Inhibitor of Pathological Calcium Oxalate Crystallization.

Kidney stones are a pervasive disease with notoriously high recurrence rates that require more effective treatment strategies. Herein, tartronic acid is introduced as an efficient inhibitor of calcium oxalate monohydrate (COM) crystallization, which is the most prevalent constituent of human kidney stones. A combination of in situ experimental techniques and simulations are employed to compare the inhibitory effects of tartronic acid with those of its molecular analogs. Tartronic acid exhibits an affinity for binding to rapidly growing apical surfaces of COM crystals, thus setting it apart from other inhibitors such as citric acid, the current preventative treatment for kidney stones. Bulk crystallization and in situ atomic force microscopy (AFM) measurements confirm the mechanism by which tartronic acid interacts with COM crystal surfaces and inhibits growth. These findings are consistent with in vivo studies that reveal the efficacy of tartronic acid is similar to that of citric acid in mouse models of hyperoxaluria regarding their inhibitory effect on stone formation and alleviating stone-related physical harm. In summary, these findings highlight the potential of tartronic acid as a promising alternative to citric acid for the management of calcium oxalate nephropathies, offering a new option for clinical intervention in cases of kidney stones.

Association between body roundness index and prevalence of kidney stone in the U.S: a study based on the NHANES database.

OBJECTIVE: This study aimed to evaluate the potential association between the body roundness index (BRI) and kidney stone prevalence in adults in the United States. METHODS: A cohort of participants from the National Health and Nutrition Examination Survey (NHANES) database spanning 2007-2018 were gathered for analysis. Logistic regression analyses, subgroup assessments, and calculations were employed to examine the potential link between BRI and kidney stone prevalence. RESULTS: The study included 30,990 participants aged > 20 years, of which 2,891 declared a kidney stone history. After modulating all relevant confounding factors, each unit increase in the BRI was linked to a 65% increase in kidney stone prevalence (OR = 1.65, 95% CI: 1.47, 1.85). Sensitivity analyses conducted by categorizing the BRI into three groups revealed a 59% increase in kidney stone prevalence in the highest tertile BRI group compared to the lowest one (OR = 1.59, 95% CI: 1.42, 1.79). Furthermore, dose-response curves depicted a positive near-linear correlation between the BRI and the risk of kidney stone prevalence. CONCLUSION: These findings suggest a clinically noteworthy positive correlation between higher BRI values and kidney stone prevalence among the studied US adult population. However, it is essential to acknowledge that the observed relationship does not establish a causal link.

Correlation Between Hypothyroidism and Gallstone Disease in Central India.

Introduction The decreased thyroid-stimulating hormone (TSH) levels affect almost every nucleated cell in our body, which directly affects the basal metabolic rate (BMR). It tends to affect multiple organ systems in the human body. In recent times, there have been changes in lifestyle and the consumption of processed foods has increased. Thus, cholelithiasis and hypothyroidism are being encountered frequently, even in rural populations. In recent times, the overt clinical presentation of hypothyroidism is rare due to early diagnosis and treatment of the subclinical hypothyroidism state itself. Aim The aim is to determine the correlation between cholelithiasis and hypothyroidism. Methods This was a cross-sectional study done on the patients presenting to the surgical department at Acharya Vinoba Bhave Rural Hospital affiliated to Jawaharlal Nehru Medical College, Sawangi (Meghe), Wardha, Maharashtra, India between the duration from December 2020 to December 2022, having gallstone disease or with symptoms suggestive of gall bladder stones. The admitted patients were then evaluated for hypothyroidism by thyroid profile tests, and the results were documented. Using the collected data, factors such as clinical spectrum, correlation between cholelithiasis and hypothyroidism, relation with the demographic data, and body mass index (BMI) were studied. Results A total of 52 gallstone patients were included in the study. A greater number of patients were found to be above the age of 40 years (82.7%), with female preponderance (61.5%). More patients with cholelithiasis were from the group with having BMI more than normal (57.6%). More patients having both cholelithiasis and hypothyroidism were also from the group with having BMI more than normal. Most symptomatic patients complained of pain in the right hypochondriac region (88.5%). Of these 52 patients, nine (17.3%) were found to have hypothyroidism (seven were subclinical, two patients had overt clinical symptoms and signs) and the remaining 43 patients were euthyroid. Conclusions Our study supports that there is a correlation between cholelithiasis and hypothyroidism. Out of all the 52 patients, nine had hypothyroidism, seven were subclinical, and two had overt symptoms. Thus, we conclude that there is a correlation between cholelithiasis and hypothyroidism.

Paediatric Renal Stone Management in Africa: A Scoping Review and Analysis of Current Practices.

Renal stones are solid deposits formed from minerals and salts that develop within the kidneys and urinary tract. While the condition is more common among adults, children and even infants can also be affected. There is an increasing incidence of paediatric renal stones in Africa alongside multiple challenges faced in managing the condition. This scoping review aimed to provide an overview of the management modalities of paediatric renal stones in Africa. This study utilised Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) checklist. A systematic search was conducted in three electronic databases: PubMed, African Journal Online (AJOL), and Google Scholar, with 1,180 articles curated. After extensive examination, 10 articles satisfied the inclusion criteria. The review found that calcium oxalate stones were the most prevalent type, accounting for 34.03% of cases, followed by whewellite stones and ammonium urate stones. The most frequent location for stones was the kidney, and the most common symptom was pain. Abdominopelvic ultrasound was the most frequently utilised investigation. Of the 886 patients managed for renal stones, 75.4% were managed surgically, 2.9% medically, and 21.7% spontaneously resolved without intervention. This review identifies opportunities for improving the management of paediatric renal stones in Africa, including the need for standardised diagnostic and treatment protocols and the development of evidence-based guidelines tailored to the African context. Overall, this scoping review provides valuable insights into the patterns and management of paediatric renal stones in Africa and highlights the need for further research to improve the management of this condition in the region.

How traditional Chinese medicine can prevent recurrence of common bile duct stones after endoscopic retrograde cholangiopancreatography?

Common bile duct stones, as a type of cholelithiasis, are a benign biliary obstruction that easily acute abdominalgia, and Endoscopic Retrograde Cholangiopancreatography (ERCP) is usually the first choice for clinical treatment. However, the increasing recurrence rate of patients after treatment is troubling clinicians and patients. For the prevention of recurrence after ERCP, there is no guideline to provide a clear drug regimen, traditional Chinese medicine however has achieved some result in the treatment of liver-related diseases based on the "gut-liver-bile acid axis". On the basis of this, this article discusses the possibility of traditional Chinese medicine to prevent common bile duct stones (CBDS) after ERCP, and we expect that this article will provide new ideas for the prevention of recurrence of CBDS and for the treatment of cholelithiasis-related diseases with traditional Chinese medicine in future clinical and scientific research.

A retrospective cohort study: evaluating the efficacy of standard versus tubeless percutaneous nephrolithotomy (PCNL) in pediatric patients up to 18 years old.

Percutaneous nephrolithotomy (PCNL) is an endourological method applied as the standard or tubeless method for kidney stone treatment. In a retrospective cohort study, 88 surgery units involving 75 children up to 18 years old with kidney stones who underwent the surgery for 8 years in Shahid Beheshti and Boo-ali hospitals in Hamadan with one of the two methods of standard or tubeless PCNL were evaluated and compared considering the success rate of operation, hemoglobin, hematocrit drop, need for medications, need for blood transfusion, duration of surgery, and the length of hospital stay. Among the 88 units studied, 47 cases were operated with the standard PCNL and 41 cases by tubeless method. In children operated by standard and tubeless PCNL, the complete success rate of operation was 87.2% and 100% (P = 0.006), the need for blood transfusion was 2.1% and 0% (P = 1.00), the need for opioids was 27.7% and 14.6% (P = 0.134), the decrease in hemoglobin was - 1.82 ± 0.94 and -1.30 ± 0.98 mg/dl (P = 0.024), the decrease in hematocrit was - 5.40 ± 2.66 and -3.52 ± 3.11 mg/dL (P = 0.003), the mean surgery duration was 109.30 ± 53.27 and 101.46 ± 31.92 min (P = 0.414), the duration of postoperative hospitalization was 3.38 ± 1.76 and 2.46 ± 1.27 days (P = 0.007), and the frequency of fever was 23.4% and 7.3% (P = 0.04), respectively. The success rate of kidney stone surgery in children with the tubeless PCNL is higher than the standard method, and its complications are lower.

Detection of residual stones by peroral direct cholangioscopy in patients with intrahepatic stones after hepaticojejunostomy: A prospective study (with video).

BACKGROUND AND AIMS: The difficulty of radiographic confirmation of the presence of stones remains a challenge in the treatment of intrahepatic bile duct (IHBD) stones in patients after hepaticojejunostomy (HJ). Peroral direct cholangioscopy (PDCS) enables direct observation of the bile duct and is useful for detecting and removing residual stones; however, its effectiveness is not clearly established in this clinical context. METHODS: This single-center, single-arm, prospective study included 44 patients with IHBD who underwent bowel reconstruction with HJ during the study period. Stone removal was performed by short-type double-balloon enteroscopy (DBE). Following balloon-occluded cholangiography, the DBE was exchanged for an ultraslim endoscope through the balloon overtube for PDCS. The primary endpoint was the rate of residual stones detected by PDCS. Secondary endpoints were success rate of PDCS, residual stone removal with PDCS, procedure time for PDCS, procedure-related adverse events, and stone recurrence rate. RESULTS: PDCS was successful in 39/44 patients (89%), among whom residual stones were detected in 16 (41%) (95% CI: 28%-54%). Twelve patients (75%) had residual stones <5 mm. Stone removal was successful in 15 (94%) patients and median procedure time for PDCS was 16 (IQR: 10-26) min. The rate of procedure-related adverse events was 7% (3/44), all of which improved with conservative treatment. During median follow-up of 2.1 years (IQR: 1.4-3.3), the overall probability of recurrence-free status at 1, 2, and 3 years was 100%, 92%, and 86%, respectively. CONCLUSIONS: PDCS is a safe and effective procedure for complete stone removal in patients with IHBD stones after HJ.

Carboxymethylated Desmodium styracifolium polysaccharide reduces the risk of calcium oxalate kidney stone formation by inhibiting crystal adhesion and promoting crystal endocytosis.

The inhibition of cell surface crystal adhesion and an appropriate increase in crystal endocytosis contribute to the inhibition of kidney stone formation. In this study, we investigated the effects of different degrees of carboxymethylation on these processes. An injury model was established by treating human renal proximal tubular epithelial (HK-2) cells with 98.3 ± 8.1 nm calcium oxalate dihydrate (nanoCOD) crystals. The HK-2 cells were protected with carboxy (-COOH) Desmodium styracifolium polysaccharides at 1.17% (DSP0), 7.45% (CDSP1), 12.2% (CDSP2), and 17.7% (CDSP3). Changes in biochemical indexes and effects on nanoCOD adhesion and endocytosis were detected. The protection of HK-2 cells from nanoCOD-induced oxidative damage by carboxymethylated Desmodium styracifolium polysaccharides (CDSPs) is closely related to the protection of subcellular organelles, such as mitochondria. CDSPs can reduce crystal adhesion on the cell surface and maintain appropriate crystal endocytosis, thereby reducing the risk of kidney stone formation. CDSP2 with moderate -COOH content showed the strongest protective activity among the CDSPs.

Photon-Counting Detector CT for Kidney Stone Detection in Excretory Phase CT-Comparison Between Virtual Non-contrast and Virtual Non-iodine Reconstructions in a 3D Printed Kidney Phantom.

RATIONALE AND OBJECTIVES: To evaluate and compare the effectiveness of contrast media subtraction and kidney stone detection between a virtual non-iodine reconstruction algorithm (VNI; PureCalcium) and a virtual non-contrast (VNC) algorithm in excretory phase photon-counting detector computed tomography (PCD-CT), using a 3D printed kidney phantom under various tube voltages and radiation doses. MATERIALS AND METHODS: A 3D-printed kidney phantom, holding Calcium Oxalate (CaOx) and uric acid stones within contrast-enhanced calyces, was created. The calyx density mirrored the average density observed in 200 excretory phase patients (916 HU at 110 kV). Imaging was conducted on a clinical dual-source PCD-CT at 120 kV and 140 kV, with radiation doses set at 5, 10, and 15 mGy. VNI and VNC algorithms were applied. Two blinded readers evaluated the image quality, along with the degree of contrast media and kidney stone subtraction, using visual scales. Krippendorff's alpha was calculated to determine inter-reader agreement, and the Chi-squared test was employed for comparing ordinal data. RESULTS: Reader 2 rated overall image quality higher for VNI than VNC (4.90 vs. 4.00; P < .05), while Reader 1 found no significant difference (4.96 vs. 5.00; P > .05). Substantial agreement was observed between readers for contrast media subtraction in both VNC and VNI (Krippendorff's alpha range: 0.628-0.748). Incomplete contrast media subtraction occurred more frequently with VNI for both readers (Reader 1: 29% vs. 15%; P < .05; Reader 2: 24% vs. 20%; P > .05). Uric acid and smaller stones (<5 mm) were more likely to be subtracted than CaOx and larger stones in both VNC and VNI. Overall, a higher rate of stone subtraction was noted with VNI compared to VNC (Reader 1: 22% vs. 16%; Reader 2: 25% vs. 10%; P < .05). Neither radiation dose nor tube voltage significantly influenced stone subtraction (P > .05). CONCLUSION: VNC demonstrated greater accuracy than VNI for contrast media subtraction and kidney stone visibility. Radiation dose and tube voltage had no significant impact. Nonetheless, both algorithms still exhibited frequent incomplete contrast media subtraction and partial kidney stone subtraction.

Review of childhood genetic nephrolithiasis and nephrocalcinosis.

Nephrolithiasis (NL) is a common condition worldwide. The incidence of NL and nephrocalcinosis (NC) has been increasing, along with their associated morbidity and economic burden. The etiology of NL and NC is multifactorial and includes both environmental components and genetic components, with multiple studies showing high heritability. Causative gene variants have been detected in up to 32% of children with NL and NC. Children with NL and NC are genotypically heterogenous, but often phenotypically relatively homogenous, and there are subsequently little data on the predictors of genetic childhood NL and NC. Most genetic diseases associated with NL and NC are secondary to hypercalciuria, including those secondary to hypercalcemia, renal phosphate wasting, renal magnesium wasting, distal renal tubular acidosis (RTA), proximal tubulopathies, mixed or variable tubulopathies, Bartter syndrome, hyperaldosteronism and pseudohyperaldosteronism, and hyperparathyroidism and hypoparathyroidism. The remaining minority of genetic diseases associated with NL and NC are secondary to hyperoxaluria, cystinuria, hyperuricosuria, xanthinuria, other metabolic disorders, and multifactorial etiologies. Genome-wide association studies (GWAS) in adults have identified multiple polygenic traits associated with NL and NC, often involving genes that are involved in calcium, phosphorus, magnesium, and vitamin D homeostasis. Compared to adults, there is a relative paucity of studies in children with NL and NC. This review aims to focus on the genetic component of NL and NC in children.