Real-World Effectiveness of Preventive Pharmacological Therapy in Patients With Urolithiasis: A Retrospective Cohort Study.

Rationale & Objective: Data supporting the efficacy of preventive pharmacological therapy (PPT) to reduce urolithiasis recurrence are based on clinical trials with composite outcomes that incorporate imaging findings and have uncertain clinical significance. This study evaluated whether the use of PPT leads to fewer symptomatic stone events.

Study Design: Retrospective cohort study.

Magnesium Decreases Urine Supersaturation but Not Calcium Oxalate Stone Formation in Genetic Hypercalciuric Stone-Forming Rats.

Background/aims: Hypercalciuria is the most common identifiable risk factor predisposing to CaOx stone formation. Increased oral magnesium intake may lead to decreased CaOx stone formation by binding intestinal Ox leading to decreased absorption and/or binding urinary Ox to decrease urinary supersaturation. This study assessed the effect of oral magnesium on 24-h urine ion excretion, supersaturation, and kidney stone formation in a genetic hypercalciuric stone-forming (GHS) rat model of human idiopathic hypercalciuria.

Alkaline Water: Help or Hype for Uric Acid and Cystine Urolithiasis?

Purpose: The consumption of alkaline water, water with an average pH of 8 to 10, has been steadily increasing globally as proponents claim it to be a healthier alternative to regular water. Urinary alkalinization therapy is frequently prescribed in patients with uric acid and cystine urolithiasis, and as such we analyzed commercially available alkaline waters to assess their potential to increase urinary pH.

Materials And Methods: Five commercially available alkaline water brands (Essentia, Smart Water Alkaline, Great Value Hydrate Alkaline Water, Body Armor SportWater, and Perfect Hydration) underwent anion chromatography and direct chemical measurements to determine the mineral contents of each product.

Understanding the Barriers to Preventive Pharmacological Therapy Use in Older Patients With Urinary Stone Disease.

Introduction: Despite compelling clinical trial evidence and professional society guideline recommendations, prescription rates of preventative pharmacological therapy (PPT) for urinary stone disease are low. We sought to understand how patient- and clinician-level factors contribute to the decision to prescribe PPT after an index stone event.

Methods: We identified Medicare beneficiaries with urinary stone disease who had a 24-hour urine collection processed by a central laboratory.

First Reported Case of a Pyrophosphate Kidney Stone in a Human.

Urolithiasis composed of pyrophosphate salts has only been reported in animals, in the form of potassium magnesium pyrophosphate. However, there have been no reports of pyrophosphate stones in humans. Hypophosphatasia is an inherited disease characterized by low alkaline phosphatase activity and elevated levels of pyrophosphate in blood and urine.

Effect of a high-citrate beverage on urine chemistry in patients with calcium kidney stones.

A well-accepted strategy to prevent kidney stones is to increase urine volume by increasing oral intake of fluids, especially water, to lower supersaturation of the relevant, relatively insoluble salts, and thereby lower the risk of precipitation. Randomized controlled trials have shown that this strategy works. It is inexpensive, safe, and intuitively attractive to patients.

Associations between Net Gastrointestinal Alkali Absorption, 24-Hour Urine Lithogenic Factors, and Kidney Stones.

Background: It is not clear whether kidney stone formers have an abnormal handling of alkali and acid precursors in the gut, which might affect urine composition and ultimately stone formation. In this study, we aimed to investigate the determinants of net gastrointestinal alkali absorption and its associations with key urinary parameters in a large group of stone formers and non-stone formers.

Methods: Data were collected from three independent cohorts with at least one 24-hour urine collection.

Potential for Urolithiasis-related Research Using the Novel Medicare-Litholink Database.

Introduction: To overcome the data availability hurdle of observational studies on urolithiasis, we linked claims data with 24-hour urine results from a large cohort of adults with urolithiasis. This database contains the sample size, clinical granularity, and long-term follow-up needed to study urolithiasis on a broad level.

Methods: We identified adults enrolled in Medicare with urolithiasis who had a 24-hour urine collection processed by Litholink (2011 to 2016).

Beyond the Urine Anion Gap: In Support of the Direct Measurement of Urinary Ammonium.

Ammonium is a major urinary buffer that is necessary for the normal excretion of the daily acid load. Its urinary rate of excretion (UNH) may be increased several fold in the presence of extrarenal metabolic acidosis. Therefore, measurement of UNH can provide important clues about causes of metabolic acidosis.

Association of Urine Findings with Metabolic Syndrome Traits in a Population of Patients with Nephrolithiasis.

Background: The odds of nephrolithiasis increase with more metabolic syndrome (MetS) traits. We evaluated associations of metabolic and dietary factors from urine studies and stone composition with MetS traits in a large cohort of stone-forming patients.

Methods: Patients >18 years old who were evaluated for stones with 24-hour urine collections between July 2009 and December 2018 had their records reviewed retrospectively.

Neglected analytes in the 24-h urine: ammonium and sulfate.

Purpose Of Review: Evaluation of the kidney stone patient includes measurement of 24 h urine chemistries. This review summarizes the application of physiologic principles to the interpretation of urine chemistries, using sulfate and ammonium to estimate diet acid load, and the renal response.

Recent Findings: There has been increased recognition of the need to measure urine ammonium excretion in the clinical setting in order to understand renal acid excretion.

Effect of antibiotic treatment on Oxalobacter formigenes colonization of the gut microbiome and urinary oxalate excretion.

The incidence of kidney stones is increasing in the US population. Oxalate, a major factor for stone formation, is degraded by gut bacteria reducing its intestinal absorption. Intestinal O.

Complementary and Alternative Medicine Use in First-time and Recurrent Kidney Stone Formers.

Objective: To describe the patterns of complementary and alternative medicine (CAM) among patients with kidney stones and analyze the alkali content of commonly used CAM therapies.

Methods: We prospectively conducted structured interviews with patients who presented to a specialty stone clinic for the management of kidney stones. Open-ended questions were used to elicit information regarding CAM knowledge, formulation/dosing, and patterns of use.

Microbial genetic and transcriptional contributions to oxalate degradation by the gut microbiota in health and disease.

Over-accumulation of oxalate in humans may lead to nephrolithiasis and nephrocalcinosis. Humans lack endogenous oxalate degradation pathways (ODP), but intestinal microbes can degrade oxalate using multiple ODPs and protect against its absorption. The exact oxalate-degrading taxa in the human microbiota and their ODP have not been described.

Sex Differences of Kidney Stone Urine Risk Factors after Roux-en-Y Gastric Bypass.

Introduction: Roux-en-Y gastric bypass (RYGB) is a bariatric surgical procedure that is associated with higher risk of kidney stones after surgery. We examined urine composition in 18 men and women before and after RYGB to examine differences in kidney stone risk.

Methods: Three 24-h urine collections were performed before and 1 year after RYGB.

Chlorthalidone with potassium citrate decreases calcium oxalate stones and increases bone quality in genetic hypercalciuric stone-forming rats.

To study human idiopathic hypercalciuria we developed an animal model, genetic hypercalciuric stone-forming rats, whose pathophysiology parallels that of human idiopathic hypercalciuria. Fed the oxalate precursor, hydroxyproline, every rat in this model develops calcium oxalate stones. Using this rat model, we tested whether chlorthalidone and potassium citrate combined would reduce calcium oxalate stone formation and improve bone quality more than either agent alone.

Kidney stone formation and the gut microbiome are altered by antibiotics in genetic hypercalciuric stone-forming rats.

Antibiotics can alter the gut microbiome (GMB), which may be associated with stone disease. We sought to determine the effect that antibiotics have on the GMB, urine ion excretion and stone formation in genetic hypercalciuric stone-forming (GHS) rats. 116th generation GHS rats were fed a fixed amount of a normal calcium (1.

Urine and stone analysis for the investigation of the renal stone former: a consensus conference.

The Consensus Group deliberated on a number of questions concerning urine and stone analysis over a period of months, and then met to develop consensus. The Group concluded that analyses of urine and stones should be routine in the diagnosis and treatment of urinary stone diseases. At present, the 24-h urine is the most useful type of urine collection, and accepted methods for analysis are described.

Nephrolithiasis and Elevated Urinary Ammonium: A Matched Comparative Study.

Objective: To describe the associations between elevated urinary ammonium and clinical characteristics of kidney stone formers. A 24-hour urine test is recommended in high-risk patients to identify urinary abnormalities and select interventions to reduce the recurrence risk. While elevations in urine ammonium may be seen in acidosis, diarrhea, high protein diets or due to pathogenic bacteria, the clinical characteristics of these patients have not been previously described.

Using Low-Calorie Orange Juice as a Dietary Alternative to Alkali Therapy.

The pursuit of a dietary source to increase urine pH and citrate in stone formers has been ongoing for >30 years. Early evidence showed that orange juice (OJ) contains alkali and citrate, but high sugar and ascorbic acid content limited the use of OJ as a viable daily source of alkali. Recently, novel low-calorie OJs have emerged and could potentially be a better option.