Risk Factor For Nephrolithiasis Research Articles

Empagliflozin and Decreased Risk of Nephrolithiasis: A Potential New Role for SGLT2 Inhibition?

ContextDiabetes mellitus is a risk factor for nephrolithiasis. A recent observational study found that in patients with type 2 diabetes (T2D), SGLT2 inhibitor use was associated with a 49% lower risk of nephrolithiasis compared with GLP-1 receptor agonists.ObjectiveWe examined the association between nephrolithiasis and the SGLT2 inhibitor empagliflozin, using existing data from randomized clinical trials.MethodsWe pooled data from 15 081 T2D patients randomized to empagliflozin (n = 10 177) or placebo (n = 4904) from 20 phase I-IV trials, including the large cardiovascular outcome trial, EMPA-REG OUTCOME. Incident urinary tract stone events were captured using a predefined collection of MedRA terms. A sensitivity analysis using a narrower definition was also performed. Incidence rate ratios (IRR) and 95% CIs were calculated using the relative risk estimate, stratified by study.ResultsThe median exposures to study drug were 543 days (placebo) and 549 days (empagliflozin); 183 patients experienced an incident urolithiasis during follow-up (placebo, 79; empagliflozin, 104), yielding annual incidence rates of 1.01 vs 0.63 events/100 patient-years in the 2 respective groups. The IRR was 0.64 (95% CI, 0.48-0.86), in favor of empagliflozin. In the sensitivity analysis, the results were similar (IRR, 0.62 [95% CI, 0.45-0.85]).ConclusionCompared with placebo, empagliflozin therapy was associated with an approximate 40% reduced risk of urinary tract stone events in T2D patients. The underlying mechanisms are unknown but may involve altered lithogenic profile of the urine. Dedicated randomized prospective clinical trials are warranted to confirm these initial observations in patients with and without T2D.

Conhecimento e atitudes de pacientes portadores de nefrolitíase: estudo transversal

Nephrolithiasis is a common urinary tract disease with an increasing prevalence, mainly due to the lack of control of modifiable risk factors. The aim of this study was to assess the level of knowledge about risk factors for nephrolithiasis and patients' attitudes. This is a cross-sectional, observational, descriptive, and analytical study based on a review of medical records and through an online survey of patients diagnosed with nephrolithiasis during follow-up at a private nephrology clinic in Joinville, Brazil. Gender, age, comorbidities, laboratory values, knowledge, and attitudes were evaluated. An explanatory multivariate model was proposed to assess the effect of knowledge and attitudes on risk factors for nephrolithiasis. Of the 129 participants, 44 (34%) were men, median age 42 years and median time to diagnosis 5 years. Hypertension was the most prevalent comorbidity in 26%. In 42% of patients, there was weight gain since the first consultation. Alone, excessive salt consumption (98%), low water intake (77%) and high protein consumption (67%) were the most identified risk factors. After adjusting for confounders, greater knowledge was not associated with weight gain (OR=0.94; 95% CI 0.73-1.22; p=0.661) or lower salt intake (OR=1.26; 95% CI 0.95-1.67; p=0.106). Greater knowledge was associated with greater daily fluid intake (OR=1.50; 95% CI 1.11-2.01; p=0.008). Although there is little knowledge of all nephrolithiasis risk factors, measures to increase awareness can contribute to preventive attitudes.

Knowledge and attitudes of patients with nephrolithiasis: a crosssectional study

Nephrolithiasis is a common urinary tract disease with an increasing prevalence, mainly due to the lack of control of modifiable risk factors. The aim of this study was to assess the level of knowledge about risk factors for nephrolithiasis and patients' attitudes. This is a cross-sectional, observational, descriptive, and analytical study based on a review of medical records and through an online survey of patients diagnosed with nephrolithiasis during follow-up at a private nephrology clinic in Joinville, Brazil. Gender, age, comorbidities, laboratory values, knowledge, and attitudes were evaluated. An explanatory multivariate model was proposed to assess the effect of knowledge and attitudes on risk factors for nephrolithiasis. Of the 129 participants, 44 (34%) were men, median age 42 years and median time to diagnosis 5 years. Hypertension was the most prevalent comorbidity in 26%. In 42% of patients, there was weight gain since the first consultation. Alone, excessive salt consumption (98%), low water intake (77%) and high protein consumption (67%) were the most identified risk factors. After adjusting for confounders, greater knowledge was not associated with weight gain (OR=0.94; 95% CI 0.73-1.22; p=0.661) or lower salt intake (OR=1.26; 95% CI 0.95-1.67; p=0.106). Greater knowledge was associated with greater daily fluid intake (OR=1.50; 95% CI 1.11-2.01; p=0.008). Although there is little knowledge of all nephrolithiasis risk factors, measures to increase awareness can contribute to preventive attitudes.

Kidney Stones in Transfusion-Dependent Thalassemia: Prevalence and Risk Factors

Purpose: As patients with transfusion-dependent thalassemia (TDT) are living longer, novel morbidities are being recognized. The purpose of this review is to summarize the current knowledge regarding the prevalence and risk factors of nephrolithiasis in patients with TDT. Methods: A non-systematic, narrative review of the current literature published up to August 2021 was conducted. Results: Nephrolithiasis has been reported in 18% - 59% of patients with TDT, which is at least twice the prevalence in the general US population. The risk factors for nephrolithiasis can be classified into behavioral (dietary and lifestyle), environmental, metabolic, disease-specific, and genetic factors. While clarifying the true prevalence of nephrolithiasis in different age groups and diagnostic categories of TDT requires further research, prevention, and management of nephrolithiasis is a growing clinical concern. Physicians should be aware of the potential increased risk of stone disease in splenectomized and diabetic patients as well as those treated with certain chelation regimens. Conclusions: The etiology of nephrolithiasis and potential TDT-specific risk factors that may put patients at greater risk are highlighted. There is insufficient evidence at this time to recommend universal screening for nephrolithiasis using ultrasound. Evidence-based recommendations on monitoring, prevention, and management of nephrolithiasis in TDT are provided.

Removal of Large Urinary Stone Using Percutaneous Nephrolithotomy in a Patient with Crohn’s Disease

<p>Extraintestinal manifestation (EIM) of inflammatory bowel disease (IBD) is approximately 36%. Of genitourinary complications as an EIM of Crohn’s disease (CD), nephrolithiasis is the most common urinary complication in patients with CD. CD patients have been shown to have decreased urinary volume, pH, magnesium, and excretion of citrate, all of which are significant risk factors for nephrolithiasis. Genitourinary complications often occur in case of a severe longstanding disease and are associated with, the activity of bowel disease, especially in those who have undergone bowel surgery. As uncontrolled nephrolithiasis could impair renal function as well as adversely affect quality of life, proper monitoring, early detection, and prevention of the occurrence of urologic complications in CD is crucial. Few data are available about urolithiasis in patients with CD. Herein we report a case of a successful removal of a 2.7 cm calcium oxalate stone using percutaneous nephrolithotomy from a patient with long-standing CD with a previous surgery for small intestinal and colonic stricture.</p>

Risk factors for urolithiasis

Risk factors for urolithiasis Abstract. The prevalence and incidence of kidney stones has continuously increased over the last years. Recent evidence suggests that kidney stones have a substantial morbidity including chronic kidney disease and end stage kidney disease as well as significantly increased risk for cardiovascular diseases. Thus, risk stratification - especially of high-risk patients - is mandatory in the management of kidney stone patients. There is a huge variety in risk factors for nephrolithiasis including general factors (such as young age at manifestation, familial disposition), genetic or acquired diseases with risk of stone formation, drugs etc. Several prediction scores have been developed to assess recurrence risk in kidney stone formers. However, only very few studies have investigated these tools and more evidence is needed in future to proof if these scores reliably predict stone recurrence risk.

Incidence of nephrolithiasis after bladder augmentation in people with spina bifida

Risks of nephrolithiasis after bladder augmentation in people with spina bifida (SB) remain unclear. Annual incidence of nephrolithiasis in the general population is 0.01% for 10-14 years old, 0.07% for 15-19 years old and 0.2% for 20-24 years old. Our aim was to assess the incidence and risk factors of nephrolithiasis in SB patients after augmentation. Patients with SB and augmentation followed at our institution were retrospectively reviewed (born ≥1972, surgery 1979-2019). Patients were screened annually with renal bladder ultrasound and abdominal radiograph. Main outcome was nephrolithiasis treatment. Kaplan-Meier survival and Cox proportional hazards analysis were used. Possible predictors were assessed using stepwise forward selection (variables with p<0.1 on univariate analysis included in multivariate analysis). 427 patients with SB and augmentation were included (51.8% female, 74.9% shunted). Median age at augmentation was 8.5 years (median follow-up: 12.4 years, ileum segment: 81.0%, bladder neck procedure: 60.7%, urinary channel: 74.2%) and 28.8% developed bladder stones. Overall, 47 (11.0%) patients were treated for nephrolithiasis. After correction for differential follow-up, nephrolithiasis was treated in 7.3% at 10 years, 13.2% at 15 years, and 18.0% at 20 years (Figure). Patients presented with either a urinary tract infection (46.8%), on screening (44.7%), or pain (8.5%). Stones were treated percutaneously, endoscopically or by ESWL (63.8%/34.0%/10.7%, respectively). Most were calcium stones (58.3%). On multivariate analysis, compared to younger patients, patients augmented at ≥10 years of age had 1.84 times the risk of nephrolithiasis (p=0.01). Nephrolithiasis was more common in those who developed bladder stones (HR=3.00, p<0.0001). Among those with both renal and bladder stones, bladder stones typically preceded nephrolithiasis (55.2%), were treated concurrently (31.0%) and 13.8% occurred after nephrolithiasis. Gender, wheelchair use, bowel segment used, MACE and skeletal fractures were not associated with higher nephrolithiasis risk (p≥0.11). This study of a large cohort of SB patients with long-term follow-up highlights that the risk of nephrolithiasis is cumulative and related to bladder stone formation, age at augmentation and time since augmentation. An association with bladder stones suggests potential shared metabolic causes. The study's retrospective design likely led to underestimating the risk of nephrolithiasis by not capturing spontaneously passed stones. Approximately 1% of patients with SB develop nephrolithiasis annually after augmentation. Close long-term surveillance after augmentation is strongly indicated, as nephrolithiasis incidence in augmented patient with SB is at least 10 times higher than general population. Patients with bladder stones are especially at risk.

Gender-related differences in the risk factors for repeat stone surgery.

Our objective was to analyze and compare the associations between potential risk factors for nephrolithiasis and repeat stone surgery in male and female patients. We retrospectively analyzed 1970 patients who had stone surgery at our institution in the period from January 2009 to May 2017, were older than 18years and had at least 12months of postoperative follow-up. Our definition of surgical recurrence included repeat surgery on the same renal unit or on the opposite renal unit if the original imaging did not demonstrate significant stones on that side. Uni- and multivariate Cox regression models were built for each gender. We also explored the interactions between gender and other patient's characteristics in their effect on the risk of recurrence. Ureteroscopy was the most common treatment modality for both first (83%) and repeat (87%) procedures. Over a mean follow-up of 4.3years (median 3.8, interquartile range 2.2-6.0), 413 (21.0%) patients had a surgical recurrence. In multivariate analyses, hypertension, diabetes, Caucasian race and younger age (less than 60years) were significantly associated with the risk of surgical recurrence only in females. Interaction between these characteristics and gender was significant indicating a larger effect on the risk of surgical recurrence in females compared to males. Our study demonstrated a number of differences in the predictors of repeat surgery for nephrolithiasis between males and females. If confirmed by future studies these differences may be helpful for optimizing nephrolithiasis prevention efforts.

Calcium Citrate Versus Calcium Carbonate in the Management of Chronic Hypoparathyroidism: A Randomized, Double-Blind, Crossover Clinical Trial.

ABSTRACTIn hypoparathyroidism (HypoPT), calcium supplementation is virtually always required, although the disease is likely to be associated with an increased risk of nephrolithiasis. The use of calcium citrate (Ca‐Cit) theoretically could have a positive impact on the nephrolithiasis risk because citrate salts are used to reduce this risk. Our objective was to evaluate the potential therapeutic advantage of Ca‐Cit in comparison with calcium carbonate (CaCO3) in HypoPT, on nephrolithiasis risk factors, as well as to their ability to maintain desirable serum calcium levels. We also evaluated these preparations on quality of life (QOL). This randomized, double‐blind, crossover trial recruited 24 adults with postsurgical chronic hypoparathyroidism at Campus Bio‐Medico University of Rome. Participants were randomized 1:1 to Ca‐Cit or CaCO3 for 1 month and then crossed over to the other treatment for another month. The primary outcomes were changes in albumin‐adjusted serum calcium and in ion activity product of calcium oxalate levels (AP[CaOx] index). Secondary efficacy outcomes included changes in SF‐36 survey score, fatigue score, constipation, and adverse events. No difference in terms of AP(CaOx) index was observed between the two groups. However, Ca‐Cit was associated with a significant reduction in the oxalate/creatinine ratio compared with CaCO3 (−2.46 mmol/mol [SD 11.93] versus 7.42 mmol/mol [SD 17.63], p = 0.029). Serum calcium and phosphorus concentration was not different between the two calcium preparations. Ca‐Cit was associated with less constipation (p = 0.047). No difference was found in QOL scores. Although Ca‐Cit did not modify the AP(CaOx) index when compared with CaCO3, it was associated with a reduction in urinary oxalate excretion that could have a potential beneficial effect on nephrolithiasis risk. These results are likely to have clinical implications in HypoPT, particularly those who do not tolerate CaCO3 and those affected by nephrolithiasis. A longer‐term experience is needed to confirm these findings. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Genome-wide association study of nephrolithiasis in an Eastern European population.

Nephrolithiasis is a urological pathology that occurs at high rates and carries a great burden in terms of costs. The probability of recurrence is significant, necessitating improvements in prophylaxis and understanding of the disease mechanism. Despite the high heritability of this disease, only five genome-wide association studies (GWAS) of nephrolithiasis have been published. We selected 335 unrelated confirmed nephrolithiasis cases from two major sample collection projects (blood and buccal swabs) in Romania. DNA was extracted from whole blood and buccal swabs at deCODE Genetics (Reykjavik, Iceland) and genotyped. Single-nucleotide polymorphisms identified from this GWAS implicated biological pathways and gene ontologies involving solute transport, renal physiology, and calcium homeostasis. Three loci especially emerged as candidates with a highly significant association with nephrolithiasis: RS10917682 in Regulator of G protein signaling 5, which has crucial roles in mRNA regulation and has been linked to renal cell carcinoma; RS1118528 in Solute carrier family 25 member 24, which encodes a mitochondrial ATP-Mg/phosphate carrier protein that likely influences a variety of important cellular pathways; and the TOX2-associated locus rs4437026, because TOX2 is upregulated in several tumor types and linked to tumor progression. This study is the largest kidney stone-related GWAS reported in an Eastern European population and the first GWAS performed in a Romanian population to investigate the genetic risk factors for nephrolithiasis. We identified several loci that warrant further investigation for a better understanding of this highly heritable condition.

Nonalcoholic Fatty Liver Disease Is an Independent Risk Factor for Nephrolithiasis in Women: Findings from NHANES III.

Objective: To determine if radiologically diagnosed nonalcoholic fatty liver disease (NAFLD) is an independent risk factor for nephrolithiasis using data from National Health and Nutrition Examination Survey III (NHANES III). Patients and Methods: NHANES III participants aged 20-74 years who underwent hepatobiliary ultrasound were classified as with NAFLD (moderate or severe hepatic steatosis in absence of other known causes of liver disease; n = 2498) or without NAFLD (controls; n = 9361). Risk of nephrolithiasis caused by NAFLD was estimated using logistic regression with propensity score adjustment. Secondary outcomes included medical stone management, lithotripsy, and surgical stone removal. Results: Participants with NAFLD were older (48.7 ± 0.4 vs 43.3 ± 0.3 years, p < 0.001) and exhibited greater prevalence of all components of metabolic syndrome: obesity (48% vs 21%), impaired glucose tolerance (17% vs 11%), diabetes mellitus (15% vs 6%), hypertension (36% vs 24%), and gout (4% vs 2%) (all p < 0.001). After adjusting for demographic, lifestyle, and metabolic factors, NAFLD was associated with increased risk nephrolithiasis (odds ratio [OR] = 1.29, 95% confidence interval [CI] [1.02-1.61], p = 0.03). The association persisted in women (OR = 1.65, 95% CI [1.17-2.32], p = 0.004) but not in men (OR = 1.04, 95% CI [0.77-1.40], p = 0.80). NAFLD was not associated with increased occurrence of medical management (OR = 1.31, 95% CI [0.84-2.05], p = 0.24), lithotripsy (OR = 1.61, 95% CI [0.83-3.33], p = 0.20), or surgical stone removal (OR = 0.83, 95% CI [0.48-1.44], p = 0.52). Conclusions: In a large U.S. population-based cross-sectional analysis, NAFLD was found to be associated with increased risk of nephrolithiasis in women after adjusting for demographic, clinical, and metabolic factors.

788 - Investigating risk factors of nephrolithiasis from the clinical images to the genetic bioinformatics

788 - Investigating risk factors of nephrolithiasis from the clinical images to the genetic bioinformatics

Metabolic risk factors in children with kidney stone disease: an update.

The prevalence of kidney stones in children has significantly increased in the past few decades, with concomitant increased morbidity and healthcare costs worldwide. Assessing metabolic risk factors is essential for diagnosis and specific treatment. The objective of this retrospective study is to identify the epidemiological and clinical characteristics of children under 17years of age, as well as the metabolic risk factors of nephrolithiasis. A total of 300 children with kidney stone disease were included to undergo several clinical tests using a standardized protocol. The mean age was 11.2years, and the male:female ratio was 1.15:1.0. Biochemical abnormalities were found in 89.3% of all cases. A single urine metabolic risk factor was present in 52.6% (n = 141) of the patients, and multiple risk factors were present in 36.7% (n = 106). Idiopathic hypercalciuria (alone or in combination) and hypocitraturia (alone or in combination) were the most frequent risk factors identified in 47.0% and 39.6% of these patients, respectively. Renal colic and/or unspecified abdominal pain were the most frequent forms of presentation (76.9%), followed by hematuria in 64.4% with 97.5% of stones located in the upper urinary tract. A positive family history in first-degree and second-degree relatives was found in 64.8% of boys and 61.8% of girls. We conclude that specific urinary metabolic risk factors can be found in most children with kidney stones, with hypercalciuria and hypocitraturia being the most common diagnoses. Graphical abstract .

Risk of Kidney Stones: Influence of Dietary Factors, Dietary Patterns, and Vegetarian-Vegan Diets.

Nephrolithiasis is a common medical condition influenced by multiple environmental factors, including diet. Since nutritional habits play a relevant role in the genesis and recurrence of kidney stones disease, dietary manipulation has become a fundamental tool for the medical management of nephrolithiasis. Dietary advice aims to reduce the majority of lithogenic risk factors, reducing the supersaturation of urine, mainly for calcium oxalate, calcium phosphate, and uric acid. For this purpose, current guidelines recommend increasing fluid intake, maintaining a balanced calcium intake, reducing dietary intake of sodium and animal proteins, and increasing intake of fruits and fibers. In this review, we analyzed the effects of each dietary factor on nephrolithiasis incidence and recurrence rate. Available scientific evidence agrees on the harmful effects of high meat/animal protein intake and low calcium diets, whereas high content of fruits and vegetables associated with a balanced intake of low-fat dairy products carries the lowest risk for incident kidney stones. Furthermore, a balanced vegetarian diet with dairy products seems to be the most protective diet for kidney stone patients. Since no study prospectively examined the effects of vegan diets on nephrolithiasis risk factors, more scientific work should be made to define the best diet for different kidney stone phenotypes.

Recurrence of nephrolithiasis: incidence and risk factors in Egyptian patients

Introduction Recurrence of nephrolithiasis is common. The knowledge of its incidence and risk factors is the base for proper prophylaxis and preservation of renal function. Objective The aim was To study the recurrence rate and risk factors of nephrolithiasis in Egyptian patients. Patients and methods Files of 974 patients with nephrolithiasis (634 males and 340 females, aged 7–70 years) were reviewed. They were managed between 2008 and 2009, with a 10-year follow-up period since the first stone episode for recurrence. Stone characteristics (sizes, sites, and multiplicity), treatment type, post-treatment residual stones, family history, BMI, and recurrence rate were included. Results Of the 974 patients, stone recurrence rate was 44.45% within 10 years of follow-up. Recurrence was significantly higher in young age group of less than 20 years, male sex, average BMI, and positive family history (61.14, 52.99, 50.99, and 55.82%, respectively) within 10 years. Recurrence was significantly higher with stone size greater than 2 cm (24.20%) at the second 5-year follow-up. Recurrence was significantly higher with multiple (56.59%), pelvicalyceal (59.83%), and bilateral (66.95%) renal stones within 10 years. It was significantly higher with shock wave lithotripsy (20.89%) within the second 5-year follow-up, and with presence of residual stones (32.66%) within the first 5-year follow-up. Conclusion Stone recurrence rate increases with increase in observation time. Risk factors for recurrence are young age of onset; male sex; normal BMI; positive family history; large size, multiple, bilateral, and pelvicalyceal stone; shock wave lithotripsy treatment; and presence of residual stones.

The role of phototherapy in neonatal nonphysiologic jaundice as a risk factor for nephrolithiasis

The role of phototherapy in neonatal nonphysiologic jaundice as a risk factor for nephrolithiasis

ASSOCIATION OF NEPHROLITHIASIS WITH DRINKING WATER QUALITY AND DIET IN PAKISTAN

Bad water quality has serious implications for human health, which may include gastrointestinal, liver, respiratory diseases and even cancer. In view of drinking water hardness in the study area, it was hypothesized that bad water quality has some association with the renal disorders. The possible association between nephrolithiasis, drinking water quality and diet in human subjects in district Abbottabad, Pakistan was investigated. Drinking water samples were collected from different areas (total number, n=100) and analyzed for various physico-chemical properties like turbidity, electrical conductivity, and pH by using standard methods. The concentration of total hardness ranged from 250 mgL-1 to 800 mgL-1 which exceeded the standard value of 60 mgL-1 and the water was found to contain high content of calcium ions. Kidney stones analysis reports of affected subjects (n=100) were examined for the type of stone. The calculi collected showed various shapes and were composed of calcium oxalate (88%), struvite (4%), uric acid (7%) and mix of calcium oxalate and uric acid (1%). Oxalate rich diet was another important risk factor for nephrolithiasis. The patients were consuming 100-300 mg day-1 of dietary oxalate. In conclusion, the quality of drinking water and diet habits contributed to nephrolithiasis.

Hypercalciuria: its value as a predictive risk factor for nephrolithiasis in asymptomatic primary hyperparathyroidism?

The latest guidelines of the 4th International Workshop on Asymptomatic Primary Hyperparathyroidism (aPHPT) reintroduced hypercalciuria (i.e. urinary calcium > 400mg/day) as criterion for surgery. However, the value of hypercalciuria as a predictor of nephrolithiasis and the correct cut-off values still need to be confirmed. To evaluate the prevalence of silent kidney stones in a large series of patients with aPHPT and the sensibility, specificity and predictive value of different cut-off values of hypercalciuria in identifying patients with nephrolithiasis. One hundred seventy-six consecutive patients with aPHPT were evaluated at our Institution by serum and urinary parameters and kidney ultrasound. Silent nephrolithiasis was found in 38 (21.6%) patients. In the univariate and multivariate model, hypercalciuria was a predictor of nephrolithiasis using the criterion of 400mg/24h [(OR 2.30, (1.11-4.82) P = 0.025], 4mg/kg/bw [OR 2.65, (1.14-6.25) P = 0.023], gender criterion [OR 2.79, (1.15-6.79) P = 0.023] and the cut-off value derived from the ROC analysis [(> 231mg/24h) OR 5.02 (1.68-14.97) P = 0.004]. Despite these several predictive criteria, however, hypercalciuria had a low positive predictive value (PPV), ranging from 27.4 to 32.7%. Hypercalciuria is a predictor of nephrolithiasis, but its PPV is low.

Cortisol and 11 beta-hydroxysteroid dehydrogenase type 2 as potential determinants of renal citrate excretion in healthy children.

In patients with Cushing disease, renal citrate excretion is reduced. A low urinary citrate concentration is a risk factor for nephrolithiasis. Since higher acid loading is one major determinant of reduced citrate excretion, we aimed to examine whether glucocorticoids still within the physiological range may already impact on urinary citrate excretion independently of acid-base status. Overall, 132 healthy prepubertal participants of the DOrtmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study who had collected two successive 24-h urine samples (at 1 and 2 years) before the start of their pubertal growth spurt were included in the study. Net acid excretion capacity (NAEC), urinary potential renal acid load (PRAL), creatinine, calcium, and various cortisol metabolites were measured in all samples. Glucocorticoid quantification was done by GC-MS and radioimmunoassay. In regression models multivariable-adjusted for 24-h urinary PRAL, NAEC, creatinine and calcium, urinary free cortisol (UFF), 6β-hydroxycortisol, and 20α-dihydrocortisol showed significant inverse relationships (P ≤ 0.02) with 24-h renal citrate output. By contrast, the estimate of renal 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2), i.e., the ratio of urinary free cortisone/UFF, associated positively with urinary citrate (P = 0.04). In line with studies in hypercortisolic state, even moderately high cortisol levels in healthy children, still within the physiological range, may negatively impact on the kidney's citrate excretion. Besides, a higher 11β-HSD2 activity, favoring cortisol inactivation, is paralleled by an increased citrate excretion.

P134 - Risk factors for nephrolithiasis in patients with metabolic bone disorders and hypovitaminosis D: Effects of cholecalciferol supplementation

P134 - Risk factors for nephrolithiasis in patients with metabolic bone disorders and hypovitaminosis D: Effects of cholecalciferol supplementation