Stone Risk Factors Research Articles

Kidney Stone Prevention

Kidney stone disease (KSD) (alternatively nephrolithiasis or urolithiasis) is a global health care problem that affects people in almost all of developed and developing countries. Its prevalence has been continuously increasing with a high recurrence rate after stone removal. Although effective therapeutic modalities are available, preventive strategies for both new and recurrent stones are required to reduce physical and financial burdens of KSD. To prevent kidney stone formation, its etiology and risk factors should be first considered. Low urine output and dehydration are the common risks of all stone types, whereas hypercalciuria, hyperoxaluria, and hypocitraturia are the major risks of calcium stones. In this article, up-to-date knowledge on strategies (nutrition-based mainly) to prevent KSD is provided. Important roles of fluid intake (2.5-3.0 L/d), diuresis (>2.0-2.5 L/d), lifestyle and habit modifications (for example, maintain normal body mass index, fluid compensation for working in high-temperature environment, and avoid cigarette smoking), and dietary management [for example, sufficient calcium at 1000-1200 mg/d, limit sodium at 2 or 3-5 g/d of sodium chloride (NaCl), limit oxalate-rich foods, avoid vitamin C and vitamin D supplements, limit animal proteins to 0.8-1.0 g/kg body weight/d but increase plant proteins in patients with calcium and uric acid stone and those with hyperuricosuria, increase proportion of citrus fruits, and consider lime powder supplementation] are summarized. Moreover, uses of natural bioactive products (for example, caffeine, epigallocatechin gallate, and diosmin), medications (for example, thiazides, alkaline citrate, other alkalinizing agents, and allopurinol), bacterial eradication, and probiotics are also discussed.

Physical activity can influence the relationship between ethylene oxide and risk of kidney stones: A cross-sectional study from the NHANES 2013-2016.

Ethylene oxide (EO) is known to cause inflammatory damage, and suitable physical activity can reportedly affect the risk of kidney stones. In this study, we aimed to investigate the relationship between EO and kidney stones and whether physical activity can potentially influence the relationship between EO and kidney stones. Overall, 3,336 adult participants were included; of them, 330 (9.9%) had a self-reported history of kidney stones. Data were obtained from the National Health and Nutrition Examination Survey 2013-2016. Physical activity was calculated using metabolic equivalent, weekly frequency, and duration. Logistic regression and restricted cubic spline (RCS) curves were used to explore the association between physical activity, EO, and kidney stones. Dose-response curves from the RCS showed a nonlinear positive association between EO and kidney stones. Multivariate logistic regression analysis revealed an adjusted odds ratio (aOR) of 1.548 (95% confidence interval 1.123-2.135, P = 0.008) for the risk of kidney stones among participants in the highest quartile (Q4) group compared with those in the lowest quartile (Q1) group. Furthermore, compared to the Q1 group, the aOR for risk of kidney stones in the Q4 group was 1.326 in participants without physical activity, a decreased risk (aOR 1.239) in participants with low physical activity, and an increased risk (aOR 1.981) in those with high physical activity. This study suggests that EO is a risk factor for kidney stones and that suitable physical activity may moderate this relationship to some extent; however, excessive physical activity can exacerbate this relationship.

Incidence of Kidney Stones After Metabolic and Bariatric Surgery—Data from the Scandinavian Obesity Surgery Registry

PurposeObesity is associated with increased incidence of kidney stones, a risk further increased by metabolic and bariatric surgery, particularly after procedures with a malabsorptive component. However, there is a paucity in reports on baseline risk factor and on larger population-based cohorts. The objective was to evaluate incidence and risk factors for kidney stones after bariatric surgery by comparing them to an age-, sex-, and geographically matched cohort from the normal population.Material and MethodsPatients operated with primary Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), or biliopancreatic diversion with duodenal switch (BPD-DS) from 2007 until 2017 within the Scandinavian Obesity Surgery registry were matched 1:10 to controls from the normal population. Hospital admission or outpatient visits due to kidney stones registered in the National Patient Registry were considered as endpoint.ResultsThe study included 58,366 surgical patients (mean age 41.0±11.1, BMI 42.0±5.68, 76% women) with median follow-up time 5.0 [IQR 2.9–7.0] years and 583,660 controls. All surgical procedures were associated with a significantly increased risk for kidney stones (RYGB, HR 6.16, [95% CI 5.37–7.06]; SG, HR 6.33, [95% CI 3.57–11.25]; BPD/DS, HR 10.16, [95% CI 2.94–35.09]). Higher age, type 2 diabetes hypertension at baseline, and a preoperative history of kidney stones were risk factors for having a postoperative diagnosis of kidney stones.ConclusionPrimary RYGB, SG, and BPD/DS were all associated with a more than sixfold increased risk for postoperative kidney stones. The risk increased with advancing age, two common obesity-related conditions, and among patients with preoperative history of kidney stones.Graphical

Pancreatic exocrine insufficiency is a risk factor for kidney stones in patients with chronic pancreatitis

IntroductionMost patients with chronic pancreatitis (CP) develop pancreatic exocrine insufficiency (PEI) over the course of the disease. PEI may lead to hyperoxaluria and development of urinary oxalate stones. It has been postulated that the patients with CP may be at increased risk of kidney stone formation, but the data is scarce. We aimed to estimate incidence and risk factors for nephrolithiasis in a Swedish cohort of patients with CP. Patients and methodsWe performed retrospective analysis of an electronical medical database of patients diagnosed with definite CP during 2003–2020. We excluded patients <18 years of age, those with missing relevant data in medical charts, patients with probable CP (according to the M-ANNHEIM classification system) and those in whom kidney stones were diagnosed before CP diagnosis. ResultsSome 632 patients with definite CP were followed over a median of 5.3 (IQR 2.4–6.9) years. There were 41 (6.5%) patients diagnosed with kidney stones, of whom 33 (80.5%) were symptomatic. Comparing to patients without kidney stones, patients with nephrolithiasis were older, with median age of 65 (IQR 51–72) years, and a male predominance (80% vs 63%). Cumulative incidence of kidney stones was 2.1%, 5.7%, 12.4% and 16.1% at 5, 10, 15, and 20 years after CP diagnosis, respectively. Multivariable cause-specific Cox regression analysis revealed PEI as independent risk factor for nephrolithiasis (adjusted HR 4.95, 95%CI 1.65–14.84; p = 0.004). Another risk factors were increase in BMI (aHR 1.16 95% CI 1.04–1.30; p = 0.001 per unit increment), and a male sex (4.51, 95% CI 1.01–20.3, p = 0.049). ConclusionPEI and increase in BMI are risk factors for kidney stone development in patients with CP. Male CP patents are particularly at increased risk of nephrolithiasis. This should be taken into consideration in general clinical approach to raise awareness among patients and medical workers.

National analysis of urinary cadmium concentration and kidney stone: Evidence from NHANES (2011-2020).

The association between urinary cadmium and kidney stone risk is inconsistent in previous studies, which needs further exploration. This study was performed to explore the association between urinary cadmium and kidney stone. Data from the National Health and Nutrition Examination Survey (2011-2020) were included and further analyzed. Urinary cadmium was stratified into quartiles with quartile 1 (Q1: 0.025-0.104 μg/L) and quartile 4 (Q4: 0.435-7.581 μg/L). Further weighted logistic regression was adopted to evaluate the association between urinary cadmium and kidney stone. A subgroup analysis was used to verify the findings. The non-linear association was examined using the restricted cubic spline (RCS) regression. A total of 9,056 adults aged 20 years and above were included in this study. In the fully adjusted model, an increased risk of kidney stones was identified for quartile 2 (OR = 1.40, 95% CI = 1.06-1.84, P < 0.05), quartile 3 (OR = 1.18, 95% CI = 0.88-1.59, P > 0.05), and quartile 4 (OR = 1.54, 95% CI = 1.10-2.06, P < 0.05). A similar association was found between continuous cadmium increase and OR of kidney stones in the fully adjusted model (OR = 1.13, 95% CI = 1.01-1.26, P < 0.05). The RCS also indicated a non-linear association between urinary cadmium concentration and kidney stone risk (P for non-linear < 0.001). In summary, cadmium exposure is identified as a risk factor for kidney stones in this study. Their non-linear association makes demands on early intervention for the cadmium-exposed population. Medical interventions for kidney stone prevention should take cadmium exposure into account.

Kidney Stones - What should You know?

Introduction: Kidney stones are mineral deposits in the renal calyces and pelvis that are found free or attached to the renal papillae. The risk of developing kidney stones is 10 to 15 percent in the United States and Europe, although this number is trending higher. Contributing risk factors for kidney stones are obesity, insulin resistance, gastrointestinal pathology, living in warmer climates, certain dietary patterns and medications. In this article we reviewed the epidemiology, symptoms and treatment of acute and chronic kidney stones and also prevention of stones formation in urinary tract. Material and methods: The work was based on medical articles collected in PubMed, websites and medical books. The research was conducted by looking at keywords such as: "Kidney Stones", "Renal Colic" and “Rirs”. Conclusions: The interdisciplinary approach, education of the patient and multiple endourological techniques can provide us with many solutions in the treatment of this contition. Doctors should adjust treatment to provide the best therapeutic effects.

Risk Factors of Incident Kidney Stones in Indian Adults: A Hospital-Based Cross-Sectional Study.

Background The diverse manifestations of urolithiasis providevery interesting epidemiological data. This has prompted various studiesto look into the etiopathogenesis of renal stones, which is believed to be multifactorial, both exogenous and endogenous. VDR Fok1 is a risk factor for renal stone formation and could cause the formation of renal stones through the mechanism of crystal induction and crystallization in the urine. While a few recent studies have shown the role of heavy metals like cadmium and lead in the formation of renal stones, the current knowledge is still insufficient. Methods This case-control prospective study was conducted in Guru Teg Bahadur (GTB) Hospital, a tertiary care facility in Delhi with 30 cases and 30 controls. Patients visiting the department of surgery between November 2011 and April 2013 were enrolled in the study. Cases were defined as patients with renal stones diagnosed on the basis of history and radiological investigations. Controls were selected from the patients admitted to the department of surgery for reasons other than renal stones. The study protocol was approved by the Institutional Ethical Committee of the University College of Medical Sciences, GTB Hospital, Delhi. Written informed consent was obtained from all patients.A structured questionnaire was used to collect data.Metal levels were analyzed by an atomic absorption spectrophotometer (Shimadzu Flame AA-680, Shimadzu Corp., Kyoto, Japan)at Delhi University. The vitamin D receptor gene was measured using genomic DNA.Horizontal agarose gel electrophoresis was used for the quantification of the genomic DNA. Results There were 30 cases and 30 controls in the study. Stress was more prevalent among cases (63%) compared to controls (36%). Nearly 83% of cases had the ff allele of the Vitamin D receptor gene compared to 46% of controls. The median arsenic and lead levels were higher among cases compared to controls.In the unadjusted model of logistic regression, we found stressed patients had three times higher odds of developing renal stones compared to non-stressed patients (OR (95% CI): 2.98 (1.04-8.52); p=0.04). Similarly, patients with higher blood concentrations of arsenic and lead had higher odds of developing renal stones compared to those with lower concentrations. Conclusions There was a definitive role of heavy metals, including lead, cadmium, and arsenic, seen with renal stones. A significant association was seen between the ff allele of VDR polymorphism (Fok1 enzymes) and patients with renal stones. Other parameters, including male and stress factors, seem to have an important role in renal stone formation.

Retracted: Efficacy of Super-Mini-PCNL and Ureteroscopy in Kidney Stone Sufferers and Risk Factors of Postoperative Infection.

[This retracts the article DOI: 10.1155/2022/4733329.].

Prevalence and risk factors of kidney stone disease in population aged 40–70 years old in Kharameh cohort study: a cross-sectional population-based study in southern Iran

BackgroundKidney stone is the major cause of morbidity, and its prevalence is increasing in the world. This study aimed to assess the prevalence and risk factors of kidney stone in the adult population of southern Iran based on the data of the Kharameh Cohort Study.MethodsThis cross-sectional study was conducted on 10,663 individuals aged 40–70 years old, using the baseline data of Kharamah cohort study, which started in 2014. Among all participants, 2251 individuals had a history of kidney stone. The participants’ demographic characteristics, behavioral habits, and the history of underlying diseases were investigated. The crude and Age Standardized Prevalence Rate of kidney stones was calculated. Also, logistic regression was used to identify the predictors of kidney stone. To check the goodness of fit index of the model, we used the Hosmer–Lemeshow test. All analyses were performed in STATA software.ResultsThe prevalence of kidney stone was estimated 21.11%. Also, the Age Standardized Prevalence Rate in men and women was calculated 24.3% and 18.7%, respectively. The mean age of the participants was 52.15 years. Higher prevalence of kidney stone was seen in women aged 40–50 years (40.47%, p = 0.0001) and moderate level of social economic status (31.47%, p = 0.03), men with overweight (44.69%, p < 0.0001) and those in a very high level of social economic status (35.75%, p = 0.001). The results of multiple logistic regression showed that the chance of having kidney stone was 1.17 times higher in diabetic individuals, 1.43 times higher in hypertensive individuals, 2.21 times higher in individuals with fatty liver, and 1.35 times higher in individuals with overweight. The level of socio economic status, male sex, and age were the other factors related to kidney stone.ConclusionIn this study, underlying diseases such as fatty liver, diabetes, and hypertension as well as age, male sex, overweight, and high social economic status were identified as important risk factors for kidney stone. Therefore, identifying individuals at risk of kidney stone and providing the necessary training can greatly help to reduce this disease. However, health policymakers should prepare preventive strategies to reduce the occurrence of kidney stone.

OGBN P10 Laparoscopic management of cholecystoduodenal and cholecystocolic fistulas: technical considerations and postoperative outcomes

Abstract Background Cholecystoduodenal and cholecystocolic fistulas are rare complications of gallstone disease. They are usually diagnosed intraoperatively, posing significant surgical challenges. The aim of this study is to review the incidence, presentations, difficulty grading, technical aspects and their management outcomes on a unit adopting a policy of index admission cholecystectomy for all comers with biliary emergencies. Methods A prospectively maintained database of all laparoscopic cholecystectomy (LC) and laparoscopic common bile duct exploration (LCBDE) performed over a 30 years period between 1992 to 2022 by a single surgeon was reviewed. All biliary emergencies who were fit for anaesthesia were managed with an intention to treat during the index admission. Procedures involving cholecystoenteric fistulas or suspicious attachments were analysed. The clinical presentation, imaging, operative findings and outcomes were analysed. All suspicious cholecystoenteric attachments were dissected and encircled, confirming a fistula was achieved by access through the gallbladder lumen and, in most cases, obtaining either a duodenography or a colonography before disconnecting and repairing the fistula. Although staplers were not used in this series the technique may enhance the security of closure and prevent occasional complications resulting from minor intraoperative or postoperative leakage. Results 59/6000 (1%) patients had cholecystoduodenal and cholecystocolic fistulas (46) or dense fibrous attachments (13) where careful dissection revealed no obvious fistula. 67.8% were female and the median age was 68 years. 33 (56%) were emergency admissions, including 20 jaundiced and 8 with acute cholecystitis. Of 26 admitted electively 6 had previous acute cholecystitis. 32 (54.2%) had risk factors for CBD stones. ERCP was done in 5 and of cross sectional imaging in 15 patients only one suspected a cholecystocolic fistula. LCs were classified difficulty grade IV (28) or V (31). 29 (49.15) required LCBDE: 11 (18.6%) by trancystic exploration and 18 (30.5%) via choledochotomy. 12 patients had Mirizzi abnormalities and 3 had gallbladder, biliary or duodenal cancers. Subhepatic drains were used in 54 (91.5%). Median operative time was 145 minutes (range 35–375). One patient was converted to open due to significant adhesions. Perioperative complications occurred in 32%: 4 t-tube complications, 3 bile leaks, 3 chest infections, 3 intraabdominal collections requring relaparoscopy and 6 miscellaneous. The rate of complications specific to the presence of such fistulas was only 12%. There were 2 deaths with respiratory infection. Median hospital stay was 10 days (range 1–160). Conclusions When dense fibrosis and adhestions to bowel loops are encountered, a high index of suspicion is particularly important as 44% present electively with chronic symptoms. When an attachment is suspected to be a fistula it should be isolated, approached through the gallbladder lumen to confirm a fistula. Ligation is carried out before division and appropriately securing the fistula using seromuscular sutures. The laparoscopic approach to managing cholecystoduodenal and cholecystocolic fistulas is not currently widely practiced as the operative findings results in a low threshold for open conversion. However, laparoscopic resolution is feasible with appropriate training and experience thus avoiding conversion to open surgery which may help reduce the relatively high morbidity associated with such encounters.

Efficacy and safety of percutaneous nephrolithotripsy in elderly patients: a retrospective study

BackgroundPercutaneous nephrolithotripsy (PCNL) is difficult to perform for elderly patients; thus, this study aimed to assess its efficacy and safety in elderly patients aged > 70 years, note any associations between outcomes and patient characteristics, and summarize relevant themes and observations.MethodsData from patients older than 70 years who had undergone PCNL for upper urinary tract calculi between January 2016 and January 2021 was retrospectively analyzed. Risk factors for postoperative complications and residual stones were analyzed using multivariate logistic regression.ResultsA total of 116 elderly patients underwent 122 PCNL operations, of which six underwent secondary PCNL operations, and all of which were successfully completed. The average age was 74.6 ± 4.3 years; the average stone size and operation time were 3.5 ± 1.8 (1.2–11 cm), and 71.8 ± 34.1 min, respectively. Of the participants, 16 or 13.8% had postoperative complications and 29 (25%) had residual stones after operation. The stone free rate was 75%. Multivariate analysis revealed that an American Score of Anesthesiology III was an independent risk factor for postoperative complications (odds ratio [OR] = 4.453, p = 0.031), and staghorn calculi were independent risk factors for postoperative residual calculi (OR = 31.393, p = 0.001).ConclusionPCNL was shown to be safe and effective for elderly patients aged > 70 years. Further, ASA III was an independent risk factor for postoperative complications, and staghorn calculi were independent risk factors for postoperative residual calculi in elderly patients.

Causes of the Primary Urinary Bladder Stones in Children and their Prevension in Population of Dera Ismail Khan, KPK, Pakistan

Introduction: History of the stone disease dates back to ancient Egyptian era. Stones involving the urinary bladder are usually 5% of the disease burden. In the Europe and America prevalence of primary bladder stones is decreased significantly in the recent ere but it is still common in developing nations including Pakistan. Materials and methods: We retrospectively collected the data from the parents of the affected children during the follow up. We took the detailed interview regarding the amount of water used by the child, amount and type of milk given and type of food given to the child. Results: We were operated 148 children with the bladder stones in the department of urology DHQ-TH D.I. Khan. There were 117 (79.05%) boys and 31 (20.94%) girls. The children below the 5 years of age were 101 (68.24%).139 (94%) of the patients belonged to the rural areas of the D.I. Khan. There were 132 (89.19%) children those were malnourished. The duration of breast feeding was approximately 12 to 15 months. They started the weaning at 7–8 months with the wheat bread and tea and also added the potatoes in the diet. With increasing age they added the pulses and the vegetables. Only 10.81% of the parents given the child meat, eggs and milk in the diet. 104 (70.27%) of the children were dehydrated. Conclusion: The risk factors for primary bladder stones in the children are multifactorial. Important factors are dehydration, low protein diet and foods deficient in phosphate contents. Keyword: Primary Bladder Stones; Children; Pakistan; Risk Factors.

Association between plasma cadmium and renal stone prevalence in adults in rural areas of Guangxi, China: a case–control study

BackgroundKidney stones have become a worldwide public health problem. The purpose of this research is to study the relationship between plasma cadmium level and the prevalence of kidney stones in an adult population.MethodsThe data of this study were based on a current survey conducted from December 2018 to November 2019 in Gongcheng Yao Autonomous County, Guangxi, China. A total of 940 study subjects of the same sex and age (within 2 years of each other) according to 1:1 matching were selected for a case–control study. The diagnosis of kidney stones was based on the presence of strong light spots, patches, clusters, or bands within the renal sinus region, followed by an echo-free bundle of acoustic images. Plasma metal elements were determined by the metal plasma method. The relationship between plasma cadmium concentration and the prevalence of kidney stones was assessed using logistic regression and restricted cubic spline regression.ResultsThe crude ratio for kidney stones in the highest quartile of plasma cadmium was 1.164 (95% CI, 1.121 to 2.324) compared with the lowest quartile. A positive correlation was found between the two (P for trend = 0.039). After adjusting for potential confounders, the ratio of plasma cadmium to kidney stones in the highest quartile was 1.606 (95% CI, 1.100 to 2.344) compared with the lowest quartile, and the findings remained unchanged.ConclusionThe odds of kidney stones in adults increased with increasing plasma cadmium exposure, and high plasma cadmium may be a risk factor for kidney stones.

Risk factors and management of biliary stones after living donor liver transplant and its effect on graft outcome.

BackgroundBile stones are associated with numerous complications in liver transplant recipients. Endoscopic retrograde cholangiopancreatography (ERCP) has been proven to be safe and highly effective in dealing with most post-transplant biliary complications.ObjectiveThe objective of this study was to identify the possible risk factors for bile stone formation on top of biliary stricture, the effects of stones on graft outcomes, and their management.MethodsThis case–control study included 83 patients who underwent living donor liver transplant (LDLT) and suffered from postoperative biliary stricture with or without stones. Patients were divided into two groups. Group 1 (n = 55) included patients with biliary strictures with no stones and group 2 (n = 28) included patients who developed stones on top of biliary strictures. Data about the recipient and donor characteristics, surgical technique, blood lipid profile, immunosuppressive drugs, post-transplant complications, and interventions were collected from the medical records.ResultsThe frequency of hepatitis C virus (HCV) was significantly higher in group 2 compared to group 1 (71.4% vs. 47.3%, p = 0.036). The body mass index (BMI) of the donors was significantly higher in group 2 than in group 1 (25.17 ± 2.53 vs. 23.68 ± 2.63, p = 0.015). Episodes of acute rejection were significantly higher in group 2 than in group 1 (21.4% vs. 5.5%, p = 0.027). The ERCP was sufficient in most of the cases (89.2%) to ensure biliary drainage. The identified independent risk factors for biliary stones included HCV, biliary drain, donor's BMI, and serum cholesterol level.ConclusionPositive HCV, biliary drain insertion, donor's BMI, and serum cholesterol level were independent risk factors for developing bile stones on top of biliary strictures. Biliary stones were associated with high episodes of acute graft rejection, and they could be successfully managed by the ERCP modality.

Dietary Risk Factors for Incident and Recurrent Symptomatic Kidney Stones

ObjectiveTo compare dietary factors between incident symptomatic stone formers and controls, and among the incident stone formers, to determine whether dietary factors were predictive of symptomatic recurrence. Patients and MethodsWe prospectively recruited 411 local incident symptomatic kidney stone formers (medical record validated) and 384 controls who were seen at Mayo Clinic in Minnesota or Florida between January 1, 2009, and August 31, 2018. Dietary factors were based on a Viocare, Inc, food frequency questionnaire administered during a baseline in-person study visit. Logistic regression compared dietary risk factors between incident symptomatic stone formers and controls. Incident stone formers were followed up for validated symptomatic recurrence in the medical record. Cox proportional hazards models estimated risk of symptomatic recurrence with dietary factors. Analyses adjusted for fluid intake, energy intake, and nondietary risk factors. ResultsIn fully adjusted analyses, lower dietary calcium, potassium, caffeine, phytate, and fluid intake were all associated with a higher odds of an incident symptomatic kidney stone. Among incident stone formers, 73 experienced symptomatic recurrence during a median 4.1 years of follow-up. Adjusting for body mass index, fluid intake, and energy intake, lower dietary calcium and lower potassium intake were predictive of symptomatic kidney stone recurrence. With further adjustment for nondietary risk factors, lower dietary calcium intake remained a predictor of recurrence, but lower potassium intake only remained a predictor of recurrence among those not taking thiazide diuretics or calcium supplements. ConclusionEnriching diets in stone formers with foods high in calcium and potassium may help prevent recurrent symptomatic kidney stones.

The effect of metabolic risk factors on urinary stone composition: An observational study.

To investigate how the risk factors of metabolic diseases affect urinary stone composition, particularly uric acid (UA) stones. Overall, 583 patients with data on urinary stone composition were retrospectively analyzed and classified into UA and nonUA stone formers according to the presence of the UA component. Various factors were compared between both groups. Participants were categorized according to age, glucose level, HbA1c level, and estimated glomerular filtration rate (eGFR) into subgroups, and the incidence of UA stone was compared. Overall, 137 UA stone formers (23.5%) and 446 nonUA stone formers (76.5%) were included. Mean age and male-to-female ratio were higher in the UA group than in the nonUA group. The rates of diabetes mellitus (DM), hypertension, chronic kidney disease, and coronary artery disease, all of which were associated with differences in urinary stone composition, were higher in the UA group than in the nonUA group. The UA group exhibited lower mean eGFR and higher glucose and HbA1c levels. Similarly, the UA group had higher mean UA levels and predictably lower urinary pH. In subgroup analysis, higher age, glucose level, HbA1c level, and lower eGFR were associated with an increased risk of UA stone formation. In the multivariate logistic regression analysis, the UA group showed a significantly higher age (P < .001), DM frequency (P = .049), and HbA1c level (P = .032), but significantly lower eGFR than the nonUA group (P < .001). Age and DM were independent risk factors for UA urolithiasis, implying a relationship between urinary stone composition and metabolic diseases. Additionally, renal function and HbA1c level were risk factors for UA stones.

Heterocyclic Aromatic Amines and Risk of Kidney Stones: A Cross-Sectional Study in US Adults.

BackgroundHeterocyclic aromatic amines (HAAs) are a group of harmful substances produced while cooking meat at high temperatures. This study aimed to investigate the relationship between HAAs and the occurrence of kidney stones.MethodsData on the level of four HAAs, including 2-Amino-9H-pyrido [2, 3-b] indole (A-α-C), 1-Methyl-9H-pyrido [3, 4-b] indole (Harman), 9H-Pyrido [3, 4-b] indole (Norharman), and 2-Amino-1-methyl-6-phenylimidazo [4, 5-b] pyridine (PhIP), in the urine from adult participants were extracted from the 2013–2014 NHANES database. Propensity score matching (PSM) was used to balance confounding variables between the stone former and non-stone former groups, and logistic regression analysis was performed to analyze the relationship between HAAs and the occurrence of kidney stones.ResultsOf the 1,558 eligible participants, a history of kidney stones was self-reported by 140 (9.0%). Compared to non-stone formers, stone formers had higher concentrations of A-α-C, Harman, and Norharman and lower concentrations of PhlP in urine. After adjusting for all other confounding variables, multivariate logistic regression analysis showed that the high-Harman group had a higher risk of kidney stones than the low-Harman group [adjusted odds ratios (aOR) = 1.618, 95% CI: 1.076–2.433, p = 0.021]. After PSM analysis, Harman concentration remained a risk factor for kidney stones (high-Harman group vs. low-Harman group: aOR = 1.951, 95% CI: 1.059–3.596, p = 0.032).ConclusionIncreased urinary Harman concentrations are associated with an increased risk of kidney stones in the general US population.

Small-molecule inhibitor of intestinal anion exchanger SLC26A3 for treatment of hyperoxaluria and nephrolithiasis.

Nephrolithiasis is a common and recurrent disease affecting 9% of the US population. Hyperoxaluria is major risk factor for calcium oxalate kidney stones, which constitute two-thirds of all kidney stones. SLC26A3 (DRA, downregulated in adenoma) is an anion exchanger of chloride, bicarbonate, and oxalate thought to facilitate intestinal oxalate absorption, as evidenced by approximately 70% reduced urine oxalate excretion in knockout mice. We previously identified a small-molecule SLC26A3 inhibitor (DRAinh-A270) that selectively inhibited SLC26A3-mediated chloride/bicarbonate exchange (IC50 ~ 35 nM) and, as found here, oxalate/chloride exchange (IC50 ~ 60 nM). In colonic closed loops in mice, luminal DRAinh-A270 inhibited oxalate absorption by 70%. Following oral sodium oxalate loading in mice, DRAinh-A270 largely prevented the 2.5-fold increase in urine oxalate/creatinine ratio. In a mouse model of oxalate nephropathy produced by a high-oxalate low-calcium diet, vehicle-treated mice developed marked hyperoxaluria with elevated serum creatinine, renal calcium oxalate crystal deposition, and renal injury, which were largely prevented by DRAinh-A270 (10 mg/kg twice daily). DRAinh-A270 administered over 7 days to healthy mice did not show significant toxicity. Our findings support a major role of SLC26A3 in intestinal oxalate absorption and suggest the therapeutic utility of SLC26A3 inhibition for treatment of hyperoxaluria and prevention of calcium oxalate nephrolithiasis.

Physical Activity Reduces the Effect of High Body Mass Index on Kidney Stones in Diabetes Participants From the 2007-2018 NHANES Cycles: A Cross-Sectional Study.

BackgroundBody mass index (BMI) is a vital risk factor for kidney stones, but physical activity may reduce the incidence of kidney stones. However, it remains unknown whether physical activity reduces the effect of high BMI on kidney stones in diabetes participants.MethodsWe included clinical information from 4,008 adult participants with diabetes from the National Health and Nutrition Examination Survey (NHANES) database from 2007 to 2018. Univariate and multivariate logistic regression analyses were used to analyze the relationship between BMI and kidney stones, as well as the risk of BMI and kidney stones in different physical activity subgroups.ResultsA total of 4,008 diabetic participants were included in this study, of whom 652 (16.3%) self-reported a history of kidney stones. Logistic regression analysis showed a positive association between BMI and kidney stones. After adjusting for other confounders, the adjusted ORs for the risk of kidney stones was 1.514 (95% CI, 1.134–2.022, p = 0.005) for participants with BMI ≥30 kg/m2 among all participants; the risk of kidney stones was elevated (OR = 1.572, 95% CI, 1.134–2.022, p = 0.005) in group without physical activity, and a reduced risk (OR = 1.421, 95% CI, 0.847–2.382, p = 0.183) in the group with physical activity. Furthermore, similar results were found in most subgroups.ConclusionOur study suggests that high BMI is a risk factor for diabetes kidney stone participants and that physical activity may moderate this relationship to some extent.

Associations of Obesity and Neighborhood Factors With Urinary Stone Parameters

Obesity is associated with kidney stone disease, but it is unknown whether this association differs by SES. This study assessed the extent to which obesity and neighborhood characteristics jointly contribute to urinary risk factors for kidney stone disease. This was a retrospective analysis of adult patients with kidney stone disease evaluated with 24-hour urine collection (2001-2020). Neighborhood-level socioeconomic data were obtained for a principal component analysis, which identified 3 linearly independent factors. Associations between these factors and 24-hour urine measurements were assessed using linear regression as well as groupings of 24-hour urine results using multivariable logistic regression. Finally, multiplicative interactions were assessed testing effect modification by obesity, and analyses stratified by obesity were performed. Analyses were performed in 2021. In total, 1,264 patients met the study criteria. Factors retained on principal component analysis represented SES, family structure, and housing characteristics. On linear regression, there was a significant inverse correlation between SES and 24-hour urine sodium (p=0.0002). On multivariable logistic regression, obesity was associated with increased odds of multiple stone risk factors (OR=1.61; 95% CI=1.15, 2.26) and multiple dietary factors (OR=1.33; 95% CI=1.06, 1.67). No significant and consistent multiplicative interactions were observed between obesity and quartiles of neighborhood SES, family structure, or housing characteristics. Obesity was associated with the presence of multiple stone risk factors and multiple dietary factors; however, the strength and magnitude of these associations did not vary significantly by neighborhood SES, family structure, and housing characteristics.