Role, Cost, and Availably of Urinary pH Monitoring for Kidney Stone Disease-A Systematic Review of the Literature.

PURPOSE OF REVIEW: Urinary pH is an important factor related to renal stone disease, and it plays an essential role in stone prevention. Monitoring of urinary pH by patients at home provides information that can help to assess the treatment needed by each patient. We conducted a systematic review is to assess the available evidence concerning urinary pH monitoring methods along with their accuracy, cost, and usefulness by patients with urolithiasis. RECENT FINDINGS: A total of 9 articles were included (1886 urinary pH measurements). They reported information about urinary dipsticks, portable electronic pH meters and electronic strip readers, amongst other methods. Accuracy was compared with a laboratory pH meter (gold standard). Urinary dipsticks were found to be not accurate enough to guide clinical decision making and portable electronic pH meters showed promising results. Urinary dipsticks are neither precise nor accurate enough. Portable electronic pH meters seem to be more accurate, easy to use, and cost-effective. They are a reliable source for patients to use at home in order to prevent future episodes of nephrolithiasis.

[Prevention of urolithiasis using febuxostat in patients with metabolic syndrome].

INTRODUCTION: Urolithiasis is a chronic highly recurrent disease. The development of new methods of its pathogenetic treatment and prevention is a priority task of practical urology. AIM: To evaluate the clinical efficiency and safety of Febuxostat-SZ and to develop the rec-ommendations for its use in patients with uric acid stones. MATERIALS AND METHODS: The analysis of 525 patients with urolithiasis was carried out. On the basis of a comprehensive examination, they were divided into two groups: in the group 1, pa-tients (n=231) had urolithiasis and metabolic syndrome, while in the group 2 (n=294), only urolithia-sis was diagnosed without metabolic syndrome. In both groups, depending on the stone composi-tion, in addition to general measures, specific stone prevention was carried out, which included die-tary regimen and drug therapy. RESULTS: Uric acid excretion after 6 months of therapy in patients with urolithiasis and meta-bolic syndrome decreased from 9.8+/-1.8 to 3.9+/-1.1 mmol/l, urinary excretion of citrates and urine acidity increased from 0.8 +/-0.6 to 2.5+/-0.8 mmol/l and from 5.4+/-0.5 to 6.3+/-0.5, respectively, while serum uric acid level decreased from 451.4+/-15.1 up to 385.2+/-16.2 mmol/l. In the group of patients who, in addition to prescribing stone prevention, underwent correction of the metabolic syndrome, uric acid excretion after 3 months decreased by half: from 9.7+/-1.9 to 5.0+/-1.2 mmol/l, urine pH and citrate excretion increased from 5.4+/-0.4 to 6.3+/-0.5 and from 0.8+/-0.5 to 2.3+/-1.0 mmol/l, respective-ly, while serum uric acid level decreased from 459.5+/-17.7 to 370.9+/-15.1 mmol/l after 6 months of treatment. CONCLUSION: The use of Febuxostat-SZ in the complex therapy of urinary stone disease showed high efficiency in normalizing urine acidity, the level of daily excretion and serum uric acid level, as well as satisfactory tolerability and a minimal profile of side effects.

Strategies for preventing end stage kidney disease: The impact of kidney stone disease on Chronic Kidney Disease in Pakistan.

Chronic Kidney Disease (CKD) is one of the major noncommunicable diseases that have social and economic impacts along with day-to-day health-related problems. Kidney stone disease is still one of the major causes of CKD in Pakistan. Kidney stone disease is a preventable cause of renal failure, if detected and treated early. Kidney stone is prevalent in the stone belt areas in our country which are located in rural areas. The treatment is very costly, and mostly available only in large cities. The treatment requires tertiary care setup and expertise. Therefore, there is a need to focus on the preventive strategies which are mainly dietary and lifestyle modifications, along with public awareness programmes. Nephrologists and urologists along with the government should take interest and give priority to CKD due to stone disease.

Protective roles of flavonoids and flavonoid-rich plant extracts against urolithiasis: A review.

In the urinary system, urolithiasis is the third prevalent disorder which causes severe pain in individuals. Urinary stones are composed of calcium oxalate (CaOx) and calcium phosphate in approximately 80% of patients. Although various drugs and surgery operations are used to treat the disease, side effects of drugs and the high recurrence after therapy in patients cannot be ignored. Flavonoids are a large group of plant polyphenols with presumed beneficial effects on several common diseases. Whereas, a very few have reached clinical use. The results of recent studies have shown that the plant flavonoids could effectively inhibit the formation of CaOx stones in vitro and in vivo, correlating with their diuretic, antioxidant, anti-inflammatory, antibacterial properties and other protective effects. Thus, the flavonoids or flavonoid-rich plant extracts endowed with anti-urolithiasis activities and probable mechanisms of actions were reviewed. In addition, we also put forward some issues needed to be concerned in future investigations as well as offered prospects and challenges for developing the plant flavonoids into drugs for stone prevention.

The Emergence of Kidney Stone Disease During Childhood-Impact on Adults.

PURPOSE OF REVIEW: The goal of this chapter is to review the recent epidemiologic trends of kidney stone disease and discuss the impact of the increasing incidence of nephrolithiasis among children on adults with respect to extra-renal manifestations, surgical management, and secondary prevention. RECENT FINDINGS: Among pediatric patients, kidney stone disease has been increasing at a rate of approximately 5-10% annually. Kidney stone disease has been associated with increased risks of coronary heart disease, chronic kidney disease, hypertension, and decreased bone mineral density, which is concerning for patients diagnosed at a young age. Improvements in endo-urology have allowed for less invasive surgical treatment of stones in the pediatric population. However, current guidelines often lack recommendations for evaluation, medical, and surgical management of children with kidney stone disease. Nephrolithiasis is a disorder of mineral metabolism, which is beginning during childhood with increasing frequency. Kidney stone disease often exists over the lifetime and is associated with serious conditions that are important for pediatric and adult urologists to recognize and consider in their evaluation and treatment of patients.

Large-scale identification of calcium oxalate stone inhibitory proteins in normal human urine.

Recent evidence has shown that proteins in normal human urine can inhibit calcium oxalate (CaOx) kidney stone formation. Herein, we performed fast protein liquid chromatography (FPLC) to fractionate normal human urinary proteins using anion-exchange (DEAE) and size-exclusion (Superdex 200) materials. FPLC fractions (F1-F15) were examined by CaOx crystallization, growth, aggregation and crystal-cell adhesion assays. The fractions with potent inhibitory activities against CaOx crystals were then subjected to mass spectrometric protein identification. The data revealed that 13 of 15 fractions showed inhibitory activities in at least one crystal assay. Integrating CaOx inhibitory scores demonstrated that F6, F7 and F8 had the most potent inhibitory activities. NanoLC-ESI-Qq-TOF MS/MS identified 105, 93 and 53 proteins in F6, F7 and F8, respectively. Among them, 60 were found in at least two fractions and/or listed among known inhibitors with solid experimental evidence in the StoneMod database (https://www.stonemod.org). Interestingly, 10 of these 60 potential inhibitors have been reported with lower urinary levels in CaOx stone formers compared with healthy (non-stone) individuals, strengthening their roles as potent CaOx stone inhibitors. Our study provides the largest dataset of potential CaOx stone inhibitory proteins that will be useful for further elucidations of stone-forming mechanisms and ultimately for therapeutic/preventive applications.

Quercetin inhibits calcium oxalate crystallization and growth but promotes crystal aggregation and invasion.

Recent evidence has shown an association between kidney stone pathogenesis and oxidative stress. Many anti-oxidants have been studied with an aim for stone prevention. Quercetin, a natural flavonol, is one among those eminent anti-oxidants with satisfactory anti-inflammatory property to cope with renal tissue injury in kidney stone disease. Nevertheless, its direct effect (if any) on calcium oxalate (CaOx) crystals and the stone formation mechanism had not been previously explored. This study has addressed the ability of quercetin at various concentrations (2.5, 5, 10, 20, 40, 80 and 160 µM) to directly modulate CaOx crystallization, growth, aggregation, adhesion on kidney cells, and invasion through the matrix. The data have shown that quercetin significantly inhibits CaOx crystallization and crystal growth but promotes crystal aggregation in concentration-dependent manner. However, quercetin at all these concentrations do not affect CaOx adhesion on kidney cells. For the invasion, quercetin at all concentrations constantly promotes CaOx invasion through the matrix without concentration-dependent pattern. These discoveries have demonstrated for the first time that quercetin has direct but dual modulatory effects on CaOx crystals. While quercetin inhibits CaOx crystallization and growth, on the other hand, it promotes CaOx crystal aggregation and invasion through the matrix. These data highlight the role for quercetin in direct modulation of the CaOx crystals that may intervene the stone pathogenesis.

Gaps in kidney stone disease management: From clinical theory to patient reality.

With nephrolithiasis projected to affect 25% of the global population in the next three decades, there is an urgent call for innovative management strategies to prevent and reduce stone recurrence. This study aims to explore the evolving management needs in nephrolithiasis from both patient and healthcare provider perspectives. An expert-collaborative online survey comprising 10 targeted questions on kidney stone management was developed and disseminated. This survey was designed to gather comprehensive insights from patients, physicians and dietician and other person in the field of nephrolithiasis. Analysis of responses from 120 participants, including 45 nephrologists, 38 dieticians, 11 urologists, and 14 kidney stones patients followed in our hospital, revealed critical insights. A significant 97.5% emphasized the necessity of optimizing daily water intake, and 94.1% recognized the need for practical dietary modifications. Additionally, 88.3% of respondents found timely hydration reminders beneficial. Notably, monitoring urine color and pH was valued by 85% and 84.3% of the participants, respectively. A striking disparity emerged in the perception of fatigue and wellness monitoring, with 65% of patients prioritizing fatigue monitoring, a view less shared by healthcare professionals. Similarly, 71% of patients deemed wellness monitoring essential, highlighting a gap in understanding between patients and their caregivers. This study underscores the critical need for more tailored guidance on hydration strategies and the promise of remote urine parameters monitoring in nephrolithiasis management. The findings strongly advocate for a patient-centered approach, aligning medical recommendations with patient lifestyles and experiences, to enhance the effectiveness of nephrolithiasis management.

Alkali Citrate Content of Common Over-the-Counter and Medical Food Supplements.

Objective: Potassium citrate effectively decreases kidney stone recurrence, but it is costly and associated with side effects. While several over-the-counter supplements and medical foods purport to provide sufficient citrate to prevent recurrent stones, corroborating data on their actual citrate content is limited. Materials and Methods: Nine common nonprescription products were purchased online. Reported citrate content was obtained from packaging, promotional materials, or ingredient labels. Using a single serving of each product, actual citrate, sodium, potassium, calcium, magnesium, and oxalate content was measured using spectrophotometry and chromatography. Total alkali citrate, cost, and amounts of each component per 10 mEq of alkali citrate were also calculated. Results: Nearly all products contained more citrate than advertised, except for Litholyte® powder, Litholyte® Coffee, and Horbäach® potassium citrate. Per serving, Moonstone® powder, LithoBalance™, and KSP tabs™ contained the most citrate (means of 63.9, 33.5, and 26.9 mEq, respectively). Moonstone and LithoBalance had the greatest discrepancy between total citrate and alkali citrate (15.7 and 11.8 mEq per serving, respectively). NOW® potassium citrate was least expensive ($0.04/10 mEq alkali citrate). KSP tabs delivered the most daily sodium (mean 158 mg/10 mEq alkali citrate, Litholyte Coffee provided the most potassium (mean of 13 mEq/10 mEq alkali citrate), and Kidney COP® provided the most calcium (mean 147 mg/10 mEq alkali citrate). Conclusion: Some common over-the-counter products contain sufficient alkali to potentially promote a citraturic response; Moonstone provides the most alkali citrate, but at a higher cost than other products. Sodium, potassium, and calcium from these products must also be considered in daily consumption.

Shockwaves and the Rolling Stones: An Overview of Pediatric Stone Disease.

Urinary stone disease is a common problem in adults, with an estimated 10% to 20% lifetime risk of developing a stone and an annual incidence of almost 1%. In contrast, in children, even though the incidence appears to be increasing, urinary tract stones are a rare problem, with an estimated incidence of approximately 5 to 36 per 100,000 children. Consequently, typical complications of rare diseases, such as delayed diagnosis, lack of awareness, and specialist knowledge, as well as difficulties accessing specific treatments also affect children with stone disease. Indeed, because stone disease is such a common problem in adults, frequently, it is adult practitioners who will first be asked to manage affected children. Yet, there are unique aspects to pediatric urolithiasis such that treatment practices common in adults cannot necessarily be transferred to children. Here, we review the epidemiology, etiology, presentation, investigation, and management of pediatric stone disease; we highlight those aspects that separate its management from that in adults and make a case for a specialized, multidisciplinary approach to pediatric stone disease.

How to Monitor Hydration Status and Urine Dilution in Patients with Nephrolithiasis.

Maintenance of hydration status requires a tight balance between fluid input and output. An increase in water loss or a decrease in fluid intake is responsible for dehydration status, leading to kidney water reabsorption. Thus, urine volume decreases and concentration of the different solutes increases. Urine dilution is the main recommendation to prevent kidney stone recurrence. Monitoring hydration status and urine dilution is key to preventing stone recurrence. This monitoring could either be performed via spot urine or 24 h urine collection with corresponding interpretation criteria. In laboratory conditions, urine osmolality measurement is the best tool to evaluate urine dilution, with less interference than urine-specific gravity measurement. However, this evaluation is only available during time lab examination. To improve urine dilution in nephrolithiasis patients in daily life, such monitoring should also be available at home. Urine color is of poor interest, but reagent strips with urine-specific gravity estimation are currently the only available tool, even with well-known interferences. Finally, at home, fluid intake monitoring could be an alternative to urine dilution monitoring. Eventually, the use of a connected device seems to be the most promising solution.

External Validation of the Recurrence of Kidney Stone Nomogram in a Surgical Cohort.

Objective: To assess the performance of recurrence of kidney stone (ROKS) nomogram in identifying first-time stone formers who will require future stone procedures. Materials and Methods: From January 2009 to February 2016, 2287 patients underwent surgical treatment for nephrolithiasis at our institution and 498 of them were eligible for this study. We defined recurrence as repeat surgery for symptomatic nephrolithiasis. We analyzed the performance of the nomogram with respect to discrimination, calibration, and the clinical net benefit. We also examined the performance of each individual variable from the nomogram. Results: Over a median follow-up of 4.8 years (mean 4.6, IQR 3.1-6.1), 88 patients (17.7%) had recurrent nephrolithiasis requiring surgical treatment. The ROKS nomogram demonstrated moderate discriminative ability (AUC 0.655 for 2 years and 0.605 for 5 years). Calibration of the ROKS nomogram-based predictions was poor and net clinical benefit was minimal. Three of 11 predictors from the nomogram were statistically significantly associated with the risk of repeat surgery, with two of them representing similar clinical scenarios, namely symptomatic and nonsymptomatic renal stones. Conclusion: ROKS nomogram demonstrated limited discrimination and calibration in predicting the risk of repeat surgery for symptomatic nephrolithiasis in our cohort of first-time stone formers. This may be caused by the differences between stone patients who do and do not require surgery and suggests the need for development of more precise prediction instruments.