Effects of a low-salt diet on idiopathic hypercalciuria in calcium-oxalate stone formers: a 3-mo randomized controlled trial

Is the "Pandemic Diet" Nonlithogenic?

Introduction and Objective: The COVID-19 pandemic and worldwide quarantine resulted in major changes in individual lifestyles. In New York State, March 16, 2020, marked the end of in-restaurant dining and a reported shift to more cooking at home. We investigated the 24-hour urine of patients with known history of nephrolithiasis to see if changes during COVID-19 pandemic altered the risk of stone disease. Methods: Retrospectively, patients with history of nephrolithiasis seen for an outpatient visit from April 1, 2020, to December 31, 2020, were studied. All patients had a 24-hour urine study "pre-COVID" defined as before March 16, 2020, "during-COVID" from March 16, 2020, to December 31, 2020; if available, "post-COVID" from January 1, 2021, to October 31, 2022, was also included. Mean study values were compared using paired, two-tailed t-tests. Results: Ninety-three patients (M = 54, F = 39) with a mean age of 60 years were evaluated. Twenty-four-hour urine revealed a significant reduction in urinary sodium (uNa) levels from pre-COVID (166.15 ± 7.51 mEq/L) compared with during-COVID (149.09 ± 7.55 mEq/L) (p = 0.015) and urinary calcium (uCa) levels from pre-COVID (214.18 ± 13.05 mg) compared with during-COVID (191.48 ± 13.03 mg) (p = 0.010). Post-COVID 24-hour urine (N = 73) levels for uNa (138.55 ± 6.83 mEq/L, p = 0.0035) and uCa (185.33 ± 12.61 mg, p = 0.012) remained significantly reduced compared with pre-COVID values, but with no difference compared with during-COVID values. Upon age stratification, this significance was found only in patients younger than 65. There were no significant differences in 24-hour urine total volume, magnesium, or citrate levels. Conclusions: During the COVID-19 lockdown, dietary choices limited to home-cooked meals allowed patients to better identify their food choices. This study demonstrates that home-cooked meals improved urinary parameters minimizing lithogenic risk factors for stone formation, including hypernatriuria and hypercalciuria. That these changes persisted into the post-COVID period may indicate improved dietary practices after the lockdown ended.

The Multidisciplinary Approach in the Management of Patients with Kidney Stone Disease-A State-of-the-Art Review

Kidney stone disease has a multifactorial etiology, and evolving dietary habits necessitate continuous updates on the impact of dietary components on lithogenesis. The relationship between diseases influenced by lifestyle, such as obesity and diabetes, and kidney stone risk underscores the need for comprehensive lifestyle analysis. Effective management of kidney stones requires a multidisciplinary approach, involving collaboration among nutritionists, urologists, nephrologists, and other healthcare professionals to address the complex interactions between diet, lifestyle, and individual susceptibility. Personalized dietary therapy, based on each patient's unique biochemical and dietary profile, is essential and necessitates comprehensive nutritional assessments. Accurate dietary intake evaluation is best achieved through seven-day, real-time dietary records. Key factors influencing urinary risk include fluid intake, dietary protein, carbohydrates, oxalate, calcium, and sodium chloride. Personalized interventions, such as customized dietary changes based on gut microbiota, may improve stone prevention and recurrence. Current research suggests individualized guidance on alcohol intake and indicates that tea and coffee consumption might protect against urolithiasis. There is potential evidence linking tobacco use and secondhand smoke to increased kidney stone risk. The effects of vitamins and physical activity on kidney stone risk remain unresolved due to mixed evidence. For diseases influenced by lifestyle, conclusive evidence on targeted interventions for nephrolithiasis prevention is lacking, though preliminary research suggests potential benefits. Management strategies emphasize lifestyle modifications to reduce recurrence risks, support rapid recovery, and identify predisposing conditions, highlighting the importance of these changes despite inconclusive data.

Medical management of urolithiasis: Great efforts and limited progress

Objective

To provide a comprehensive review on the existing literature on medical management of urolithiasis.

Methods

A thorough literature review was performed using Medline, PubMed/PMC, Embase, and the Cochrane Database of Systematic Reviews up to December 2022 to identify publications on the medical management of urolithiasis. Studies that assessed dietary and pharmacologic management of urolithiasis were reviewed; studies on medical expulsive therapy were not included in this review.

Results

Medical management of urolithiasis ranges from the prophylactic management of kidney stone disease to dissolution therapies. While most treatment concepts have been long established, large randomized controlled trials are scarce. Dietary modification and increased fluid intake remain cornerstones in the conservative management of urolithiasis. A major limitation for medical management of urolithiasis is poor patient compliance.

Conclusion

Medical management of urolithiasis is more important in patients with recurrent urolithiasis and patients with metabolic abnormalities putting them at higher risk of developing stones. Although medical management can be effective in limiting stone recurrence, medical interventions often fail due to poor compliance.

Long-Term Sodium Deficiency Reduces Sodium Excretion but Impairs Renal Function and Increases Stone Formation in Hyperoxaluric Calcium Oxalate Rats

Excessive sodium intake is associated with nephrolithiasis, but the impact of sodium-deficient (SD) diets is unknown. Hence, we investigated the effects of short- and long-term SD diets on the expression of renal aquaporins and sodium transporters, and thus calcium oxalate (CaOx) crystal formation in hyperoxaluria rats. In a short-term sodium balance study, six male rats received drinking water and six received 0.75% ethylene glycol (EG) to induce hyperoxaluria. After a 30-day period of feeding on normal chow, both groups were treated with a normal-sodium diet for 5 days, followed by a sodium-free diet for the next 5 days. In a long-term SD study (42 days), four groups, induced with EG or not, were treated with normal-sodium water and sodium-free drinking water, alternately. Short-term sodium restriction in EG rats reversed the daily positive sodium balance, but progressively caused a negative cumulative water balance. In the long-term study, the abundant levels of of Na/H exchanger, thiazide-sensitive Na-Cl cotransporter, Na-K-ATPase, and aquaporins-1 from SD + EG rats were markedly reduced, corresponding to a decrease in Uosm, as compared to SD rats. Increased urine calcium, AP(CaOx)index, and renal CaOx deposition were also noted in SD + EG rats. Although the SD treatment reduced sodium excretion, it also increased urinary calcium and impaired renal function, ultimately causing the formation of more CaOx crystals.

2022 Recommendations of the AFU Lithiasis Committee: Medical management - from diagnosis to treatment

The morphological-compositional analysis of urinary stones allows distinguishing schematically several situations: dietary, digestive, metabolic/hormonal, infectious and genetic problems. Blood and urine testing are recommended in the first instance to identify risk factors of urinary stone disease in order to avoid recurrence or progression. The other objective is to detect a potential underlying pathology associated with high risk of urinary stone disease (e.g. primary hyperparathyroidism, primary or enteric hyperoxaluria, cystinuria, distal renal tubular acidosis) that may require specific management. Lifestyle-diet measures are the basis of the management of all stone types, but pharmacological treatments may be required. METHODOLOGY: These recommendations were developed using two methods: the Clinical Practice Recommendation (CPR) method and the ADAPTE method, depending on whether the question was considered in the European Association of Urology (EAU) recommendations (https://uroweb.org/guidelines/urolithiasis) [EAU 2022] and their adaptability to the French context.

24-h Urinary Calcium Excretion and Renal Outcomes in Hospitalized Patients with and without Chronic Kidney Disease

This study investigated the impact of 24-h urinary calcium excretion (UCaE) on renal function decline in hospitalized patients with and without chronic kidney disease (CKD). This study enrolled 3815 CKD patients in stages 1-4 and 1133 non-CKD patients admitted to the First Center of the Chinese PLA General Hospital between January 2014 and July 2022. The primary outcome for CKD patients was a composite of CKD progression, defined as a 40% decline in estimated glomerular filtration rate (eGFR) or end-stage kidney disease. Annual eGFR change was the secondary outcome. For non-CKD patients, the primary outcome was an eGFR decline of ≥20% or CKD incidence, while annual eGFR change was the secondary outcome. The association between UCaE and kidney function decline was assessed using Cox proportional hazards and generalized linear models. Primary outcomes were observed in 813 CKD patients and 109 non-CKD patients over a median follow-up of 3.0 and 4.1 years, respectively. For CKD patients, every 1-mmol/d increase in UCaE was associated with a 15% decreased risk of CKD progression. The hazard ratio (HR) was 0.85, with a 95% confidence interval (CI) of 0.77-0.93. For non-CKD patients, the risk of renal function decline decreased by 11%. The multivariate models indicated that there was an annual decrease in eGFR in both CKD and non-CKD patients, with a reduction of 0.122 mL/min/1.73 m²/year (p < 0.001) and 0.046 mL/min/1.73 m²/year (p = 0.004), respectively, for every 1-mmol/d increase in UCaE. CKD experiences a decrease in 24-h UCaE as early as stage 1, with a significant decline in stage 4. CKD and non-CKD patients with lower UCaE levels are at an increased risk of renal decline, regardless of other variables.

Proposal for pathogenesis-based treatment options to reduce calcium oxalate stone recurrence

Objective

Prevalence of kidney stone disease continues to increase globally with recurrence rates between 30% and 50% despite technological and scientific advances. Reduction in recurrence would improve patient outcomes and reduce cost and stone morbidities. Our objective was to review results of experimental studies performed to determine the efficacy of readily available compounds that can be used to prevent recurrence.

Methods

All relevant literature up to October 2020, listed in PubMed is reviewed.

Results

Clinical guidelines endorse the use of evidence-based medications, such as alkaline agents and thiazides, to reduce urinary mineral supersaturation and recurrence. However, there may be additional steps during stone pathogenesis where medications could moderate stone risk. Idiopathic calcium oxalate stones grow attached to Randall's plaques or plugs. Results of clinical and experimental studies suggest involvement of reactive oxygen species and oxidative stress in the formation of both the plaques and plugs. The renin-angiotensin-aldosterone system (RAAS), nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, mitochondria, and NOD-like receptor pyrin domain containing-3 (NLRP3) inflammasome have all been implicated at specific steps during stone pathogenesis in animal models.

Conclusion

In addition to supersaturation-reducing therapies, the use of anti-oxidants, free radical scavengers, and inhibitors of NADPH oxidase, NLRP3 inflammasome, and RAAS may prove beneficial for stone prevention. Compounds such as statins and angiotensin converting enzyme inhibitors are already in use as therapeutics for hypertension and cardio-vascular disease and have previously shown to reduce calcium oxalate nephrolithiasis in rats. Although clinical evidence for their use in stone prevention in humans is limited, experimental data support they be considered along with standard evidence-based medications and clinical expertise when patients are being counselled for stone prevention.

The association between dietary sodium intake and obesity in adults by sodium intake assessment methods: a review of systematic reviews and re-meta-analysis

BACKGROUND/OBJECTIVES

The scientific evidence of a sodium-obesity association is limited by sodium intake assessments. Our specific aim is to synthesize the association between dietary sodium intake and obesity across the sodium intake assessments as evidenced by systematic reviews in adults.

SUBJECTS/METHODS

A systematic search identified systematic reviews comparing the association of dietary sodium intakes with obesity-related outcomes such as body mass index (BMI), body weight, waist circumference, and risk of (abdominal) obesity. We searched PubMed on October 24, 2022. To assess the Risk of Bias in Systematic Reviews (ROBIS), we employed the ROBIS tool.

RESULTS

This review included 3 systematic reviews, consisting of 39 unique observational studies (35 cross-sectional studies and 4 longitudinal studies) and 15 randomized controlled trials (RCTs). We found consistently positive associations between dietary sodium intake and obesity-related outcomes in cross-sectional studies. Studies that used 24-h urine collection indicated a greater BMI for those with higher sodium intake (mean difference = 2.27 kg/m2; 95% confidence interval [CI], 1.59-2.51; P < 0.001; I2 = 77%) compared to studies that used spot urine (mean difference = 1.34 kg/m2; 95% CI, 1.13-1.55; P < 0.001; I2 = 95%) and dietary methods (mean difference = 0.85 kg/m2; 95% CI, 0.1-1.51; P < 0.05; I2 = 95%).

CONCLUSIONS

Quantitative synthesis of the systematic reviews has shown that cross-sectional associations between dietary sodium intake and obesity outcomes were substantially different across the sodium intake assessments. We need more high-quality prospective cohort studies and RCTs using 24-h urine collection to examine the causal effects of sodium intake on obesity.

Metabolic evaluation of first-time uncomplicated renal stone formers: A prospective study

Background

Nephrolithiasis is a global health problem. The recurrence rate after the first stone clearance is approximately 50% at 5 years. Metabolic abnormalities are an important factor responsible for stone recurrence. Our prevalidated study aimed to evaluate metabolic abnormalities associated with first-time uncomplicated renal stone formers (FTURSF).

Materials and methods

In this prospective, exploratory, time-bound, descriptive study, 30 first-time renal stone formers were evaluated for metabolic abnormalities. High-risk stone formers were excluded from the study. Data were collected in a predefined proforma, transferred to an Excel sheet, and analyzed using the Statistical Package for Social Sciences 20 and Epi Info 7. Fisher exact test, Mann-Whitney U test, paired t test, and Pearson correlation coefficient were used for statistical analyses.

Results

The mean age of the participants was 35.57 ± 11.07 years, with a male-to-female ratio of 1.72. The most common abnormality was a 24-hour urine volume of <2.5 L in 73.33% of the participants. One or more metabolic abnormalities were detected in 76.67% of the participants. Other common metabolic abnormalities detected were hypocitraturia (60%), hypercalciuria (16.67%), hyperoxaluria (13.33%), and hyperuricosuria (3.33%). Parathyroid adenoma was detected in one participant (3.33%).

Conclusions

Our study documented significant metabolic abnormalities in FTURSF. Therefore, a simplified metabolic evaluation protocol should be adopted while evaluating FTURSF. Detection of an underlying metabolic abnormality would enable the early institution of preventive measures to reduce stone recurrence and related complications.

A case-based review of dietary management of calcium oxalate stones

PURPOSE

The purpose of this paper is to help patients with calcium oxalate stones to access prevention and treatment options with dietary management.

METHODS

Typical cases in our hospital and other hospitals were selected for case review; combined with literature review through PubMed search, comprehensive analysis and suggestions were put forward.

RESULTS

By retrieving the literature with sufficient evidence, selecting, and summarizing, analysis of dietary liquid, oxalate and oxalate precursors, calcium, protein, fruits and vegetables, salt, high dietary fiber, and other content with high evidence index was carried out, respectively.

CONCLUSION

Through the retrospective analysis of typical cases and literature review, the importance of diet management in the prevention and treatment of calcium oxalate stones was emphasized again, and suggestions were put forward to promote the prevention and treatment of calcium oxalate stones.

Fluid intake recommendations in urolithiasis and general advice to patients without metabolic risk factors

Urolithiasis is a highly prevalent global disease with substantially increasing incidence in the last two decades. Data from the literature suggests that 26%-50% of patients will have a recurrence within 10 years after an initial symptomatic stone episode. Therefore, interest has been raised in preventive strategies, aiming to modify the risk factors of stone recurrence by implementing dietary and lifestyle changes and specific medical treatments for stone formers, depending on their recurrence risk factors. Certain dietary factors are thought to contribute significantly to the increased incidence of urolithiasis, particularly a diet low in fiber and high in animal protein, fat, and sodium. Fluid intake is perhaps the most important and modifiable step in the prevention of urolithiasis, irrespective of stone composition. However, the amount of fluid to be consumed and the implications of various fluid types on stone formation are still controversial. In this article, the relationship between fluid intake, beverage types and stone formation-prevention will be discussed. Moreover, general dietary recommendations for patients without metabolic risk factors will be reviewed based on the current literature.

Diet and Stone Disease in 2022

Diet plays a central role in the development and prevention of nephrolithiasis. Although pharmacologic treatment may be required for some patients who are resistant to dietary measures alone, dietary modification may be sufficient to modulate stone risk for many patients. While there is no single specialized diet for stone prevention, several dietary principles and recommendations for stone prevention are supported by practice guidelines, including adequate fluid intake, modest calcium intake, low dietary sodium, and limited animal protein. In this review, we summarized the evidence supporting these dietary recommendations and reviewed the current literature regarding specific dietary components and comprehensive diets for stone prevention.

Association of dietary patterns with gut microbiota in kidney stone and non-kidney stone individuals

The dietary patterns are closely associated with gut microbiota, which has been proved associated with kidney stones. To assess the association among the dietary patterns, gut microbiota, and kidney stones, patients with calcium oxalate stones and participants without kidney stones were recruited in West China Hospital and were divided into the low nephrolithiasis risk (LNR) and high nephrolithiasis risk (HNR) dietary pattern group based on the results of food frequency questionnaires. The genomic DNA of the fecal samples were extracted for 16S ribosomal RNA gene sequencing. The non-kidney stone (NS) group comprised 39 LNR and 45 HNR individuals, while the kidney stone (KS) group consisted of 19 LNR and 50 HNR individuals. The distribution of oxalate in urine (p < 0.01) but not calcium (p = 0.741) was significantly varied among the four groups. Significant difference was found in the dietary patterns of people with KS and NS controls (X² = 5.744, p = 0.017). Forty-six discriminative bacteria were found among different dietary patterns groups in KS patients and NS controls. Not only gut bacteria such as Pseudomonas, Sphingomonas, Hydrogenoanaerobacterium, Faecalitalea, etc., but also metabolic pathways associated with inflammation, lipid, and mineral metabolism were found more abundant in KS patients with HNR dietary pattern. It is noteworthy that g__Prevotellaceae_UCG_001, g__hgcI_clade, and g__Bradyrhizobium were negatively related to water intake but instead had a positive correlation with salt and meat intake. Our study revealed that gut microbiota with significantly different abundance existed in the HNR dietary patterns compared to the LNR counterparts in both calcium oxalate KS and NS individuals. The dietary patterns may affect the prevention and management of calcium oxalate stones by regulating the homeostasis of gut microbiota.

The genetics of kidney stone disease and nephrocalcinosis

Kidney stones (also known as urinary stones or nephrolithiasis) are highly prevalent, affecting approximately 10% of adults worldwide, and the incidence of stone disease is increasing. Kidney stone formation results from an imbalance of inhibitors and promoters of crystallization, and calcium-containing calculi account for over 80% of stones. In most patients, the underlying aetiology is thought to be multifactorial, with environmental, dietary, hormonal and genetic components. The advent of high-throughput sequencing techniques has enabled a monogenic cause of kidney stones to be identified in up to 30% of children and 10% of adults who form stones, with ~35 different genes implicated. In addition, genome-wide association studies have implicated a series of genes involved in renal tubular handling of lithogenic substrates and of inhibitors of crystallization in stone disease in the general population. Such findings will likely lead to the identification of additional treatment targets involving underlying enzymatic or protein defects, including but not limited to those that alter urinary biochemistry.

Methods for the dietary assessment of adult kidney stone formers: a scoping review

BACKGROUND

Kidney stones are a frequent and potentially severe condition, affecting 5-10% of the European population. Causes are multifactorial, diet in particular plays a major role in the formation and management of kidney stones. The aim of this scoping review is to assess the methods used to study the diet of adult kidney stone formers.

METHODS

We conducted a systematic search in Medline Ovid SP, Embase, Cinahl, Cochrane (CENTRAL), Web of Sciences databases on June 10th, 2020. Self-report methods (such as food frequency questionnaires or 24-h dietary recalls), objective nutritional biomarkers and controlled diets were considered. We analyzed the selected publications based on the origin of participants, study design and dietary assessment methods used.

RESULTS

We screened 871 publications and included 162 of them. Most studies included participants from North America and Europe and were observational. Short and cost-effective tools such as food frequency questionnaires and other questionnaires were the most frequently used. Moreover, food diary was a frequently selected method to study the diet of kidney stone formers. New technologies (e.g. online questionnaires, phone applications, connected tools) were rarely used.

CONCLUSION

Accurate reporting of the methods used in nutritional studies is of key importance to interpret results and build evidence. Assessing long-term dietary intake is still a challenge for nutritional epidemiology. A combination of self-report methods with objective dietary biomarkers and new technologies probably represents the best way forward.

The current status of preventive measures for urinary calculi in children

Urological calculus is a common disease in urology. Urological calculi are generally more common in adults but have become more common in children in recent years. Most existing studies focus on the prevention of urinary calculi in adults; there are relatively few articles on calculi in children. Reported preventive measures are not comprehensive enough, while the latest research progress has not been updated. The pathogenesis and preventive measures associated with urinary calculi have been the focus of research, but many preventive measures still need further clarification. This article reviews the progress on preventive measures for urinary calculi in children.

Global Variations in the Mineral Content of Bottled Still and Sparkling Water and a Description of the Possible Impact on Nephrological and Urological Diseases

Kidney stone disease (KSD) is a complex disease. Besides the high risk of recurrence, its association with systemic disorders contributes to the burden of disease. Sufficient water intake is crucial for prevention of KSD, however, the mineral content of water might influence stone formation, bone health and cardiovascular (CVD) risk. This study aims to analyse the variations in mineral content of bottled drinking water worldwide to evaluate the differences and describes the possible impact on nephrological and urological diseases. The information regarding mineral composition (mg/L) on calcium, bicarbonate, magnesium, sodium and sulphates was read from the ingredients label on water bottles by visiting the supermarket or consulting the online shop. The bottled waters in two main supermarkets in 21 countries were included. The evaluation shows that on a global level the mineral composition of bottled drinkable water varies enormously. Median bicarbonate levels varied by factors of 12.6 and 57.3 for still and sparkling water, respectively. Median calcium levels varied by factors of 18.7 and 7.4 for still and sparkling water, respectively. As the mineral content of bottled drinking water varies enormously worldwide and mineral intake through water might influence stone formation, bone health and CVD risk, urologists and nephrologists should counsel their patients on an individual level regarding water intake.

Nutrition and Kidney Stone Disease

The prevalence of kidney stone disease is increasing worldwide. The recurrence rate of urinary stones is estimated to be up to 50%. Nephrolithiasis is associated with increased risk of chronic and end stage kidney disease. Diet composition is considered to play a crucial role in urinary stone formation. There is strong evidence that an inadequate fluid intake is the major dietary risk factor for urolithiasis. While the benefit of high fluid intake has been confirmed, the effect of different beverages, such as tap water, mineral water, fruit juices, soft drinks, tea and coffee, are debated. Other nutritional factors, including dietary protein, carbohydrates, oxalate, calcium and sodium chloride can also modulate the urinary risk profile and contribute to the risk of kidney stone formation. The assessment of nutritional risk factors is an essential component in the specific dietary therapy of kidney stone patients. An appropriate dietary intervention can contribute to the effective prevention of recurrent stones and reduce the burden of invasive surgical procedures for the treatment of urinary stone disease. This narrative review has intended to provide a comprehensive and updated overview on the role of nutrition and diet in kidney stone disease.

Distal Renal Tubular Acidosis: ERKNet/ESPN Clinical Practice Points

Distal renal tubular acidosis (dRTA) is characterised by an impaired ability of the distal tubule to excrete acid, leading to metabolic acidosis. Associated complications include bone disease, growth failure, urolithiasis and hypokalaemia. Due to its rarity, there is a limited evidence to guide diagnosis and management, however, available data strongly suggest that metabolic control of the acidosis by alkali supplementation can halt or revert almost all complications. Despite this, cohort studies show that adequate metabolic control is present in only about half of patients, highlighting problems with treatment provision or adherence. With these clinical practice points the authors, part of the working groups tubulopathies in the European Rare Kidney Disease Reference network (ERKnet) and inherited kidney diseases of the European Society for Paediatric Nephrology (ESPN) aim to provide guidance for the management of patients with dRTA to facilitate adequate treatment and establish an initial best practice standard against which treatment of patients can be audited.

Metabolic and Clinical Characteristics of Children with Urolithiasis from Southern India

OBJECTIVE

To study the etiological profile and patterns of clinical presentations of urolithiasis (UL) in children.

METHODS

This observational study included patients <18 y with UL, who were referred to the pediatric nephrology clinic. Clinical features, family history, consanguinity and estimated glomerular filtration rate (eGFR) at presentation and follow-up were recorded. The children were evaluated using relevant blood and urine investigations.

RESULTS

A total of 72 children with UL were evaluated for the study. The etiology of UL (n = 72) included hyperoxaluria (n = 25; 34.7%), idiopathic hypercalciuria (n = 21; 29.2%), idiopathic hyperuricosuria (n = 3; 4.2%), cystinuria (n = 3; 4.2%), urate transporter defect (n = 2; 2.8%) and mixed stones (predominant component calcium oxalate) (n = 9; 12.5%). No etiology was detected in 4 cases (5.5%). Common presenting complaints included flank pain (n = 41; 56.7%), hematuria (n = 29; 40.3%), urinary tract infection (UTI) (n = 29; 40.3%) and vomiting (n = 11; 15.3%). The median age of presentation was 60 (36, 96) mo. Family history and consanguinity were present in 30 cases (41.7%) and 28 cases (38.9%) respectively. Stone analysis was done in 20 cases, of which 9 cases were mixed stones (predominant calcium oxalate) and 6 were calcium oxalate stones.

CONCLUSIONS

Among children with urolithiasis, hyperoxaluria, idiopathic hypercalciuria, idiopathic hyperuricosuria, and cystinuria were the predominant identifiable entities, together accounting for 72% of cases; and renal colic, hematuria and UTI were the commonest clinical complaints.

Modulation of Tubular pH by Acetazolamide in a Ca2+ Transport Deficient Mice Facilitates Calcium Nephrolithiasis

Proximal tubular (PT) acidosis, which alkalinizes the urinary filtrate, together with Ca²⁺ supersaturation in PT can induce luminal calcium phosphate (CaP) crystal formation. While such CaP crystals are known to act as a nidus for CaP/calcium oxalate (CaOx) mixed stone formation, the regulation of PT luminal Ca²⁺ concentration ([Ca²⁺]) under elevated pH and/or high [Ca²⁺] conditions are unknown. Since we found that transient receptor potential canonical 3 (TRPC3) knockout (KO; -/-) mice could produce mild hypercalciuria with CaP urine crystals, we alkalinized the tubular pH in TRPC3-/- mice by oral acetazolamide (0.08%) to develop mixed urinary crystals akin to clinical signs of calcium nephrolithiasis (CaNL). Our ratiometric (λ340/380) intracellular [Ca²⁺] measurements reveal that such alkalization not only upsurges Ca²⁺ influx into PT cells, but the mode of Ca²⁺ entry switches from receptor-operated to store-operated pathway. Electrophysiological experiments show enhanced bicarbonate related current activity in treated PT cells which may determine the stone-forming phenotypes (CaP or CaP/CaOx). Moreover, such alkalization promotes reactive oxygen species generation, and upregulation of calcification, inflammation, fibrosis, and apoptosis in PT cells, which were exacerbated in absence of TRPC3. Altogether, the pH-induced alteration of the Ca²⁺ signaling signature in PT cells from TRPC3 ablated mice exacerbated the pathophysiology of mixed urinary stone formation, which may aid in uncovering the downstream mechanism of CaNL.

Variations in the mineral content of bottled 'carbonated or sparkling' water across Europe: a comparison of 126 brands across 10 countries

Introduction

Kidney stone disease is a common disease with high recurrence rates. Sufficient intake of water is the cornerstone in primary prevention of stone disease. However, the mineral composition of water can affect urinary minerals and influence stone formation. The aim of this study is to assess the variation in the mineral composition of bottled sparkling or carbonated drinking water across Europe.

Material and methods

The two largest supermarket chains in each participating country were visited to obtain data on mineral composition regarding bicarbonate, calcium, magnesium, potassium, sodium and sulphates of sparkling or carbonated waters by reading the ingredient labels on the bottles supplied by the manufacturers. Alternatively, the web-shops of these supermarkets were consulted.

Results

In total, 126 sparkling water brands across ten European countries were analysed regarding mineral composition. The median concentrations per mineral varied greatly. The greatest variation in median mineral content was found for sodium and sulphates with levels ranging from 3.1 mg/l to 63.0 mg/l and 6.0 mg/l to 263.0 mg/l respectively. A wide distribution of calcium content was found in Switzerland, with calcium levels reaching up to 581.6 mg/l.

Conclusions

This study confirms that the mineral composition of sparkling or carbonated water varies greatly across Europe. Patients with kidney stone disease should be aware that the mineral content of water may influence stone formation and be mindful of the great variation that exists between different water brands. Mineral water can be a source of potential promotors or inhibitors of stone formation and patients and urologists need to be mindful of this.

Different Waters for Different Performances: Can We Imagine Sport-Related Natural Mineral Spring Waters?

Preserving the hydration status means to balance daily fluids and salt losses with gains, where the losses depend on several physiological and environmental factors. Especially for athletes, these losses could be relevant and negatively influence the performance: therefore, their hydro-saline status must be preserved with personalized pre- and rehydration plans all along the performance period. Scientific literature in this field is mainly dedicated to artificial sport drinks. Different territories in most world areas are rich in drinking natural mineral spring waters with saline compositions that reflect their geological origin and that are used for human health (often under medical prescription). However, scarce scientific attention has been dedicated to the use of these waters for athletes. We therefore reviewed the existing literature from the innovative viewpoint of matching spring water mineral compositions with different athletic performances and their hydro-saline requirements.

The association between dietary sodium intake, adiposity and sugar-sweetened beverages in children and adults: a systematic review and meta-analysis

Higher intakes of Na may contribute to weight gain. The primary aim of this systematic review and meta-analysis was to examine the relationship between dietary Na intake and measures of adiposity in children and adults. Given the previous link between Na intake and the consumption of sugar-sweetened beverages (SSB), which are a known risk factor for obesity, a secondary aim examining the relationship between Na intake and SSB consumption was assessed. A systematic literature search identified cross-sectional and longitudinal studies and randomised controlled trials (RCT) which reduced dietary Na (≥3 months). Meta-analysis was performed for outcomes with ≥3 studies. Cross-sectionally higher Na intakes were associated with overweight/obesity in adults (five studies; n 11 067; OR 1·74; 95 % CI 1·43, 2·13) and in children (three studies; n 3625, OR 3·29; 95 % CI 2·25, 4·80), and abdominal obesity (five studies; n 19 744; OR 2·04; 95 % CI 1·72, 2·42) in adults. Overall, associations remained in sensitivity analyses which adjusted for energy. Findings from longitudinal studies were inconsistent. RCT in adults indicated a trend for lower body weight on reduced-Na compared with control diets (fifteen studies; n 5274; -0·29 kg; 95 % CI -0·59, 0·01; P = 0·06); however, it is unclear if energy intakes were also altered on reduced-Na diets. Among children higher Na intakes were associated with higher intake of SSB (four studies, n 10 329, b = 22, 16 and 26 g/d); no studies were retrieved for adults. Overall, there was a lack of high-quality studies retrieved. While cross-sectional evidence indicates Na intake was positively associated with adiposity, these findings have not been clearly confirmed by longitudinal studies or RCT.

Variations in the Mineral Content of Bottled "Still" Water Across Europe: Comparison of 182 Brands Across 10 Countries

Introduction: Kidney stone disease (KSD) is a highly prevalent disease worldwide. As water intake and its mineral content influence stone formation and recurrence, patients and physicians must be aware of the mineral content of drinkable water. We analyzed commercial bottled still water within Europe to assess the variation in its mineral composition across different manufacturers and countries. Materials and Methods: Data on the mineral composition of bottled still water regarding bicarbonate, calcium, magnesium, potassium, sodium, and sulfate concentration (mg/L) were collected from ten European countries. To collect the data, the two main supermarket chains in each participating country were either visited to check for the ingredient label on bottles or the online shop was consulted through the website of the supermarket in question. Descriptive statistics such as simple boxplots were used to illustrate the variation in mineral content. Results: One hundred eighty-two different commercial water brands were analyzed. Up to a fivefold variation in average concentrations per mineral between countries was observed. For calcium, a wide distribution was found in France and Switzerland compared with other countries with calcium levels ranging from 10.5 to 565 mg/L and 8.4 to 579 mg/L, respectively. By consuming 2 L of water with such high calcium levels, the daily reference intake for calcium is already achieved. Conclusions: The mineral content of bottled still water across Europe varies greatly. For patients with KSD it is important to be aware of the mineral content of the water they drink, as it might influence stone recurrence rates and necessitate alterations of their diet.

Dietary pattern analysis among stone formers: resemblance to a DASH-style diet

Recent epidemiological studies have shown that dietary patterns may have a more persistent impact on the risk of stone formation than single nutrients of the diet. Dietary Approaches to Stop Hypertension (DASH), a low-sodium and fruits/vegetables-rich diet, has been associated with a lower risk of nephrolithiasis, due to altered urinary biochemistry. This observational study aimed to investigate whether the dietary pattern of stone formers (SF) resembled a DASH-diet and its influence on urinary lithogenic parameters. Anthropometric data, fasting serum sample, 24-h urine samples, and a 3-day food intake record under an unrestricted diet were obtained from 222 SF and compared with 136 non-SF subjects (controls). The DASH-diet food portions were determined from the food records whereas intakes of sodium chloride (NaCl) and protein (protein equivalent of nitrogen appearance, PNA) were estimated from 24-hr urinary sodium and urea. A dietary profile close to a DASH-diet was not observed in any of the groups. NaCl intake and PNA were significantly higher in SF versus non-SF (12.0 ± 5.2 v.s. 10.1 ± 3.4 g/day, p = 0.01 and 1.8 ± 0.1 v.s. 1.4 ± 0.1 g/kg/day, p = 0.03). SF exhibited a positive correlation of NaCl intake and PNA with urinary calcium, oxalate and uric acid, and of PNA with urinary sodium. SF consumed more vegetables and legumes, but less fruits and low-fat dairy items than non-SF. The present series presented a dietary profile characterized by low calcium and high salt and protein contents, not reflecting an ideal DASH-style diet pattern.

Protocols and self-checking plans for the safety of post-COVID-19 balneotherapy

During the COVID-19 pandemics, balneotherapic establishments were closed in Italy like in the rest of Europe. The Italian Foundation for Research in balneotherapy (FoRST) was asked to prepare a safety protocol to be proposed to the National Health Authorities to allow the establishments to restart their activity when possible, under safe conditions (the so-called Phase-2). The group of experts proposed the following hygienic and sanitary protocols of risk management for the initial reopening of the balneology settings in Italy. The plan aims to define the operating procedures to be implemented at the balneology establishments for the beginning of Phase-2 and to keep them constantly updated in the different periods that will characterize Phase-2 in relation to the trends of the disease. To this end the procedures, defined on the basis of the scientific state-of-the-art available today, will be updated and revised from time to time whenever further scientific evidence and directives from the Health Authorities make it necessary and/or useful.

Effect of water composition and timing of ingestion on urinary lithogenic profile in healthy volunteers: a randomized crossover trial

Kidney stone disease is a common condition with a high recurrence rate and elevated costs. Despite the well-known positive effects of high fluid intake, there are little data about the roles of water composition and timing of ingestion during the day. This study examines the effect of two different waters [calcium-bicarbonate water (CBW) and oligomineral water (OW)] consumed at different times during the day on urine composition in a group of healthy volunteers. In a cross-over randomized trial, 12 healthy volunteers were assigned to a different sequence of four combined interventions (1 L of water consumed during fasting and 1 L of water consumed with meals): CBW/OW; OW/CBW; CBW/CBW; OW/OW. Participants were instructed to follow the same diet and to avoid smoking, caffeine and other beverages during the day of intervention, and to collect their urine every 2 h during the day, followed by a single overnight collection. The relative supersaturation for calcium oxalate was higher for CBW/CBW compared with all other interventions, while relative supersaturation for calcium phosphate was lower for the combination OW/CBW with meals. Urinary excretion of oxalate was lower in all interventions including CBW, while no significant differences were found for urinary calcium. Water composition and timing of ingestion have complex and interacting effects on lithogenic risk. Depending on individual characteristics, a strategy involving either OW or a mix of CBW during meals and OW outside of meals could be effective in modulating the lithogenic profile.Trial registered at clinicaltrial.gov: Protocol ID NCT03447847.

Preliminary analysis of serum electrolytes and body mass index in patients with and without urolithiasis

OBJECTIVES

To compare body mass index (BMI); serum parameters; and urine parameters between patients with and without urolithiasis.

METHODS

Data from 1164 patients admitted to our Department of Urology from January 2011 to July 2013 were retrospectively reviewed; 714 patients (age, 5-87 years; male:female ratio, 1.8:1) exhibited urolithiasis, and 450 patients (age, 12-94 years; male:female ratio, 3.8:1) did not. Blood and urine were collected from patients the morning after hospital admission. Serum and urine parameters were checked by an automatic biochemistry analyzer. Statistical analysis included the Mann-Whitney U test and binary logistic regression.

RESULTS

Serum sodium, potassium, chloride, calcium, phosphorus, and carbon dioxide combining power significantly differed between groups. In male patients, serum sodium, calcium, and phosphorus levels were higher in the urolithiasis group, whereas serum potassium and urine pH levels were lower. In female patients, serum sodium was higher in the urolithiasis group. BMI was higher in the urolithiasis group in all patients, male and female. Respective β-values of serum sodium and BMI in male patients were 0.077 and 0.084; in female patients, these values were 0.119 and 0.102.

CONCLUSIONS

Changes in serum sodium and BMI may be involved in the pathogenesis and treatment of urolithiasis.

Prevention of recurrent urinary stone disease

PURPOSE OF REVIEW

Urinary stone disease (USD) is increasing in prevalence and recurrence is common. In pediatrics, most stones are composed primarily of calcium with the highest incidence observed in adolescents. Given the morbidity associated with USD, an in depth review of current management strategies is of paramount importance to highlight the data supporting the recommended treatments and the knowledge gaps which still exist.

RECENT FINDINGS

Several interventions for the management of recurrent calcium USD in children have been recommended based on primarily adult studies. These interventions include modification of diet and fluid intake in addition to the utilization of medications such as thiazide diuretics and citrates when supportive care is inadequate. Overall there is conflicting data in the adult literature which is further complicated by our attempts to extrapolate these data to children.

SUMMARY

Based on the currently available literature the management of USD in pediatrics should be individualized to each patient and focused on the particular metabolic risk factors that are identified during the course of their evaluation. Several interventions may be required or trialed in a particular patient to show an effect. Well designed trials to assess the efficacy of each intervention in the pediatric population are needed.

Association of kidney stone disease with dietary factors: a review

Kidney stone disease is one of the most common urologic disorders worldwide. The incidence of kidney stones disease is increasing all over the world. It is a multifactorial disease accompanied by various factors. The dietary factor is one of the most important risk factors for the formation and recurrence of kidney stone disease. Formation and recurrence of kidney stone disease can be prevented by modifying our day to day dietary habits. Fewer intakes of animal protein, higher intake of fluid, higher intake of fruits, and higher intake of green leafy vegetables, which contain a low amount of oxalate, can prevent the formation of kidney stones and recurrence of kidney stones. From this review, it may be presumed that the higher prevalence rate of kidney stone disease in northeast India may be the dietary factors accompanied by environmental and climatic conditions of the region.

Calcium Oxalate Nephrolithiasis and Gut Microbiota: Not just a Gut-Kidney Axis. A Nutritional Perspective

Recent studies have shown that patients with kidney stone disease, and particularly calcium oxalate nephrolithiasis, exhibit dysbiosis in their fecal and urinary microbiota compared with controls. The alterations of microbiota go far beyond the simple presence and representation of Oxalobacter formigenes, a well-known symbiont exhibiting a marked capacity of degrading dietary oxalate and stimulating oxalate secretion by the gut mucosa. Thus, alterations of the intestinal microbiota may be involved in the pathophysiology of calcium kidney stones. However, the role of nutrition in this gut-kidney axis is still unknown, even if nutritional imbalances, such as poor hydration, high salt, and animal protein intake and reduced fruit and vegetable intake, are well-known risk factors for kidney stones. In this narrative review, we provide an overview of the gut-kidney axis in nephrolithiasis from a nutritional perspective, summarizing the evidence supporting the role of nutrition in the modulation of microbiota composition, and their relevance for the modulation of lithogenic risk.

LIFESTYLE RISK FACTORS AND BONE MASS IN RECURRENT STONE-FORMING PATIENTS: A CROSS-SECTIONAL STUDY IN 144 SUBJECTS

Patients with urolithiasis, particularly hypercalciuria, may have reduced bone mineral density (BMD). There are numerous risk factors contributing to reduction of BMD such as advanced age, sedentary lifestyle, smoking, low calcium intake, etc. The aim of our study was to investigate the association of lifestyle risk factors and daily intake of milk and dairy products with determinants of BMD in a group of recurrent calcium stone formers (RSF) compared with healthy subjects (HS). The study was carried out at the Department of Mineral Research, Faculty of Medicine in Osijek, Croatia. The study included 144 subjects, i.e. 56 RSF and 78 HS. BMD was assessed by dual-energy x-ray absorptiometry. A standard self-reported questionnaire was used to collect data on lifestyle risk factors. Current dietary intake was assessed by personal interview that included questions about milk and dairy product intake. Low BMD was observed in 44.64% of RSF and 35.90% of HS. RSF consumed significantly less milk and dairy products than HS. Calcium restriction in dietary recommendations might be unnecessary due to the impact on bone mineral loss in RSF and dual-energy x-ray absorptiometry should be included in the routine evaluation of RSF.

A Study of Diet and Lifestyle and the Risk of Urolithiasis in 1,519 Patients in Southern China

Background

This study aimed to evaluate the risk factors associated with the development of urolithiasis in a population in Southern China.

Material/Methods

A questionnaire-based study was conducted between March 2017 to April 2018 that included 1,519 patients in Southern China and included questions on patient demographics, diet, and lifestyle. Patients were divided into the urolithiasis group who had urinary calculi and the control group.

Results

There were 829 patients (54.6%) in the urolithiasis group and 690 patients (45.4%) in the control group. Using a chi-squared (χ²) test, 13 variables were found to be significantly associated with urolithiasis, including age, physical activity, and dietary factors that included high sodium, protein, fat, lean meat, vegetables, pickled food, fluid intake, drinking habits and tea consumption, and frequency and duration of physical exercise. Multivariate logistic regression analysis showed that dietary factors, including vegetables (OR, 0.856; 95% CI, 0.769–0.948), pickled foods (OR, 1.271; 95% CI, 1.030–1.357), and animal protein intake (OR, 1.138; 95% CI, 1.031–1.258), drinking strong tea (OR, 0.793; 95% CI, 0.702–0.897), fluid intake (OR, 0.758; 95% CI, 0.644–0.816), and duration of physical exercise (OR, 0.840; 95% CI, 0.808–0.973) were significantly associated with the occurrence of urolithiasis and were independent risk factors.

Conclusions

High consumptions of pickled foods and animal protein were the main risk factors for the development of urolithiasis in a population of southern China, but high fluid intake with a preference for strong tea, a diet of vegetables, and physical exercise were protective factors.

Which Diet for Calcium Stone Patients: A Real-World Approach to Preventive Care

Kidney stone disease should be viewed as a systemic disorder, associated with or predictive of hypertension, insulin resistance, chronic kidney disease and cardiovascular damage. Dietary and lifestyle changes represent an important strategy for the prevention of kidney stone recurrences and cardiovascular damage. A full screening of risk factors for kidney stones and for cardiovascular damage should be recommended in all cases of calcium kidney stone disease, yet it is rarely performed outside of stone specialist clinics. Many patients have a history of kidney stone disease while lacking a satisfactory metabolic profile. Nonetheless, in a real-world clinical practice a rational management of kidney stone patients is still possible. Different scenarios, with different types of dietary approaches based on diagnosis accuracy level can be envisaged. The aim of this review is to give patient-tailored dietary suggestions whatever the level of clinical and biochemistry evaluation. This can help to deliver a useful recommendation, while avoiding excessive dietary restrictions especially when they are not based on a specific diagnosis, and therefore potentially useless or even harmful. We focused our attention on calcium stones and the different scenarios we may find in the daily clinical practice, including the case of patients who reported renal colic episodes and/or passed stones with no information on stone composition, urinary risk factors or metabolic cardiovascular risk factors; or the case of patients with partial and incomplete information; or the case of patients with full information on stone composition, urinary risk factors and metabolic cardiovascular profile.

Dietary phosphorus intake and blood pressure in adults: a systematic review of randomized trials and prospective observational studies

BACKGROUND

Elevated blood pressure (BP) is a major cause of preventable disease in the United States and around the world. It has been postulated that phosphorus intake may affect BP, with some studies suggesting a direct and others an inverse association.

OBJECTIVES

We systematically reviewed the literature on the association of dietary phosphorus with BP in adults and performed a qualitative synthesis.

METHODS

We included randomized and nonrandomized behavioral intervention and feeding studies (intervention studies) and prospective observational studies that measured dietary phosphorus intake or urinary phosphorus excretion and BP. We excluded studies of supplements, children, or individuals with major medical conditions. We searched PubMed, Embase, Cochrane Trials, and clinicaltrials.gov on 1 June, 2017 and 22 August, 2018. We assessed studies' risk of bias in their assessment of phosphorus exposure and BP.

RESULTS

We reviewed 4759 publications and included 14 intervention studies (2497 participants), 3 prospective observational cohorts (17,795 participants), and 2 ongoing trials. No included intervention studies were designed specifically to achieve a phosphorus contrast. Two studies found a significant positive association of dietary phosphorus with systolic BP, 4 a significant inverse association, and 8 no significant association. Four studies found a significant inverse association with diastolic BP and 10 no significant associations. Two cohorts found lower risk of incident hypertension comparing the highest with the lowest quintiles of phosphorus intake and 1 found no significant difference: HR: 0.86 (95% CI: 0.75, 0.98); HR: 0.83 (95% CI: 0.68, 1.02); and HR: 0.75 (95% CI: 0.45, 1.27), respectively.

CONCLUSIONS

We found no consistent association between total dietary phosphorus intake and BP in adults in the published literature nor any randomized trials designed to examine this association. This trial was registered at www.crd.york.ac.uk/prospero/ as CRD42017062489.

The Urological Association of Asia clinical guideline for urinary stone disease

The Urological Association of Asia, consisting of 25 member associations and one affiliated member since its foundation in 1990, has planned to develop Asian guidelines for all urological fields. The field of stone diseases is the third of its guideline projects. Because of the different climates, and social, economic and ethnic environments, the clinical practice for urinary stone diseases widely varies among the Asian countries. The committee members of the Urological Association of Asia on the clinical guidelines for urinary stone disease carried out a surveillance study to better understand the diversity of the treatment strategy among different regions and subsequent systematic literature review through PubMed and MEDLINE database between 1966 and 2017. Levels of evidence and grades of recommendation for each management were decided according to the relevant strategy. Each clinical question and answer were thoroughly reviewed and discussed by all committee members and their colleagues, with suggestions from expert representatives of the American Urological Association and European Association of Urology. However, we focused on the pragmatic care of patients and our own evidence throughout Asia, which included recent surgical trends, such as miniaturized percutaneous nephrolithotomy and endoscopic combined intrarenal surgery. This guideline covers all fields of stone diseases, from etiology to recurrence prevention. Here, we present a short summary of the first version of the guideline - consisting 43 clinical questions - and overview its key practical issues.

The Demographic Diversity of Food Intake and Prevalence of Kidney Stone Diseases in the Indian Continent

Food intake plays a pivotal role in human growth, constituting 45% of the global economy and wellbeing in general. The consumption of a balanced diet is essential for overall good health, and a lack of equilibrium can lead to malnutrition, prenatal death, obesity, osteoporosis and bone fractures, coronary heart diseases (CHD), idiopathic hypercalciuria, diabetes, and many other conditions. CHD, osteoporosis, malnutrition, and obesity are extensively discussed in the literature, although there are fragmented findings in the realm of kidney stone diseases (KSD) and their correlation with food intake. KSD associated with hematuria and renal failure poses an increasing threat to healthcare infrastructures and the global economy, and its emergence in the Indian population is being linked to multi-factorial urological disorder resulting from several factors. In this realm, epidemiological, biochemical, and macroeconomic situations have been the focus of research, even though food intake is also of paramount importance. Hence, in this article, we review the corollary associations with the consumption of diverse foods and the role that these play in KSD in an Indian context.

The potential effects of dietary food and beverage intakes on the risk of kidney stone formation

ABSTRACT Objective To determine the effect of nutritional habits on kidney stone formation and recurrence. Methods This study was conducted on 44 healthy individuals and 44 patients diagnosed with nephrolithiasis and aging between 20 and 65 years. Participants shared their salt consumption habits, daily fluid consumption amounts and general information about themselves in a questionnaire form. In addition, food and beverage consumption frequencies of participants were recorded through a food frequency questionnaire. Results Salt consumption frequencies of patients are higher than that of healthy individuals in both genders (p<0.05). It was found out that male individuals in the patient group salt dishes without tasting more frequently (p<0.05). Daily total water consumption of both genders in patient group is lower than that of healthy individuals (p<0.05). Meat consumption of male patients (51.6±31.35g/day) was found to be higher than that of healthy group (34.1±22.58g/day) (p<0.05). Additionally, individuals in the patient group consume less stinging nettle, corn, plum, loquat, orange juice and lemonade than healthy individuals (p<0.05). Conclusion Results of the study showed that total fluid intake, salt consumption habits, and vegetable, fruit and beverage consumption may be correlated with stone formation risk and nutrition habits may affect stone recurrence.

Confounding risk factors and preventative measures driving nephrolithiasis global makeup

Nephrolithiasis is increasing in developed and developing countries at an alarming rate. With the global spike in kidney stone diseases, it is crucial to determine what risk factors are influencing the current global landscape for kidney stones. Our aims for this review are: to identity and analyze the four categories of risk factors in contributing to the global scale of stone formation: lifestyle, genetics, diet, and environment; and discuss preventative measures for kidney stone formation. We also performed data search through the published scientific literature, i.e., PubMed^® and found that there is a significant link between lifestyle and obesity with cases of calcium stones. Food and Agriculture Organization of the United Nations and World Health Organization factor indicators for dietary intake and obesity, along with climate data were used to create the projected total risk world map model for nephrolithiasis risk. Complete global analyses of nephrolithiasis deplete of generalizations is nearly insurmountable due to limited sources of medical and demographic information, but we hope this review can provide further elucidation into confounding risk factors and preventative measures for global nephrolithiasis analysis.

Heritable traits that contribute to nephrolithiasis

Urinary stones tend to cluster in families. Of the known risk factors, evidence is strongest for heritability of urinary calcium excretion. Recent studies suggest that other stone risk factors may have heritable components including urinary pH, citrate and magnesium excretion, and circulating vitamin D concentration. Several risk factors assumed purely environmental may also have heritable components, including dietary intake and thirst. Thus, future studies may reveal that genetics plays an even stronger role in urinary stone pathogenesis than previously known.

Medical therapy for nephrolithiasis: State of the art

The prevalence of nephrolithiasis is increasing worldwide. Understanding and implementing medical therapies for kidney stone prevention are critical to prevent recurrences and decrease the economic burden of this condition. Dietary and pharmacologic therapies require understanding on the part of the patient and the prescribing practitioner in order to promote compliance. Insights into occupational exposures and antibiotic use may help uncover individual risk factors. Follow-up is essential to assess response to treatment and to modify treatment plans to maximize therapeutic benefit.

Diet and stone formation: a brief review of the literature

PURPOSE OF REVIEW

Urolithiasis is a very common condition, which can be accompanied by serious complications. Diagnosis, treatment, and prevention are of great cost for national health systems. Many studies have been published about the role of diet in both stone formation and prevention. The aim of this review is to summarize the most recent developments that correlate diet to lithiasis.

RECENT FINDINGS

Recurrent stone formers should undergo metabolic evaluation and stone chemical analysis. Current evidence propose difference approaches based on the metabolic disorder that is diagnosed. Diet could have a detrimental role in the prevention of recurrences. Prevention advises include increased fluid uptake, vegetables and fruit intake but decreased sugar, salt, and meat consumption.

SUMMARY

The analysis of the food contents and their role to lithogenesis prevention are of great importance. Modifying diet to prevent stones could help many people who suffer from lithiasis to avoid recurrence and the consequences. Furthermore, the cost for diagnosis and treatment could be significantly reduced. Therefore, the field of dietary factors in lithogenesis should be further investigated.

Renal stones

Renal stone disease is a worldwide problem which carries significant morbidity. It frequently requires specialist urology intervention. Patients with recurrent disease and those at high risk require specialist investigations and review. Certain cases benefit from medical and surgical intervention. In this review, we discuss the pathophysiology, risk assessment, specialist investigations and various interventions, their rationale and evidence base. This review aims to provide an update of the previous publication in 2001 in this journal on this topic.