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Dong C, Zhou J, Su X, He Z, Song Q, Song C, Ke H, Wang C, Liao W, Yang S. Understanding formation processes of calcareous nephrolithiasis in renal interstitium and tubule lumen. J Cell Mol Med 2024; 28:e18235. [PMID: 38509735 PMCID: PMC10955165 DOI: 10.1111/jcmm.18235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 02/07/2024] [Accepted: 02/28/2024] [Indexed: 03/22/2024] Open
Abstract
Kidney stone, one of the oldest known diseases, has plagued humans for centuries, consistently imposing a heavy burden on patients and healthcare systems worldwide due to their high incidence and recurrence rates. Advancements in endoscopy, imaging, genetics, molecular biology and bioinformatics have led to a deeper and more comprehensive understanding of the mechanism behind nephrolithiasis. Kidney stone formation is a complex, multi-step and long-term process involving the transformation of stone-forming salts from free ions into asymptomatic or symptomatic stones influenced by physical, chemical and biological factors. Among the various types of kidney stones observed in clinical practice, calcareous nephrolithiasis is currently the most common and exhibits the most intricate formation mechanism. Extensive research suggests that calcareous nephrolithiasis primarily originates from interstitial subepithelial calcified plaques and/or calcified blockages in the openings of collecting ducts. These calcified plaques and blockages eventually come into contact with urine in the renal pelvis, serving as a nidus for crystal formation and subsequent stone growth. Both pathways of stone formation share similar mechanisms, such as the drive of abnormal urine composition, involvement of oxidative stress and inflammation, and an imbalance of stone inhibitors and promoters. However, they also possess unique characteristics. Hence, this review aims to provide detailed description and present recent discoveries regarding the formation processes of calcareous nephrolithiasis from two distinct birthplaces: renal interstitium and tubule lumen.
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Affiliation(s)
- Caitao Dong
- Department of UrologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Jiawei Zhou
- Department of UrologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Xiaozhe Su
- Department of UrologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Ziqi He
- Department of UrologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Qianlin Song
- Department of UrologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Chao Song
- Department of UrologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Hu Ke
- Department of UrologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Chuan Wang
- Department of UrologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Wenbiao Liao
- Department of UrologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
| | - Sixing Yang
- Department of UrologyRenmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina
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Conroy DE, Marks J, Cutshaw A, Ram N, Thomaz E, Streeper NM. Promoting fluid intake to increase urine volume for kidney stone prevention: Protocol for a randomized controlled efficacy trial of the sip IT intervention. Contemp Clin Trials 2024; 138:107454. [PMID: 38253254 PMCID: PMC10923155 DOI: 10.1016/j.cct.2024.107454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Revised: 01/11/2024] [Accepted: 01/19/2024] [Indexed: 01/24/2024]
Abstract
BACKGROUND Risk of kidney stone recurrence can be reduced by increasing fluid intake and urine production but most patients fail to adhere to recommended clinical guidelines. Patients have indicated that common barriers to fluid intake include a lack of thirst, forgetting to drink, and not having access to water. We developed the sipIT intervention to support patients' fluid intake with semi-automated tracking (via a mobile app, connected water bottle and a smartwatch clockface that detects drinking gestures) and provision of just-in-time text message reminders to drink when they do not meet the hourly fluid intake goal needed to achieve the recommended volume. This trial evaluates the efficacy of sipIT for increasing urine output in patients at risk for recurrence of kidney stones. METHOD/DESIGN Adults with a history of kidney stones and lab-verified low urine production (<2 L/day) will be randomly assigned to receive either usual care (education and encouragement to meet fluid intake guidelines) or usual care plus the sipIT intervention. The primary outcome is 24-h urine volume; secondary outcomes include urinary supersaturations, past week fluid intake, and experienced automaticity of fluid intake. Outcomes will be assessed at baseline, 1 month, 3 months, and 12 months. CONCLUSIONS The sipIT intervention is the first to prompt periodic fluid intake through integration of just-in-time notifications and semi-automated tracking. If sipIT is more efficacious than usual care, this intervention provides an innovative treatment option for patients needing support in meeting fluid intake guidelines for kidney stone prevention.
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Affiliation(s)
- David E Conroy
- Department of Kinesiology, The Pennsylvania State University, University Park, PA 16802, USA.
| | - James Marks
- Department of Urology, The Pennsylvania State University, Hershey, PA 17033, USA
| | - Alyssa Cutshaw
- Department of Kinesiology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Nilam Ram
- Department of Communication and Psychology, Stanford University, Palo Alto, CA 94305, USA
| | - Edison Thomaz
- Department of Electrical and Computer Engineering, University of Texas, Austin, TX 78712, USA
| | - Necole M Streeper
- Department of Urology, The Pennsylvania State University, Hershey, PA 17033, USA
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Aksenov LI, Streeper NM, Scales CD. Leveraging behavioral modification technology for the prevention of kidney stones. Curr Opin Urol 2024; 34:14-19. [PMID: 37962162 PMCID: PMC10842369 DOI: 10.1097/mou.0000000000001142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
PURPOSE OF REVIEW The purpose of this review is to examine the use of technology to help promote and maintain behaviors that decrease stone recurrence. RECENT FINDINGS Behavior change is a complex process with various interacting components. Recent developments have sought to utilize technology in combination with behavioral change techniques to promote behavior that lowers stone recurrence risk. Smart water bottles are becoming a popular way to accurately measure fluid intake with variable impact on adherence to the recommended daily fluid intake. Mobile apps have also been explored as a method to improve fluid intake. Interventions that combine smart water bottles, mobile apps, and behavioral change techniques have shown the most promise in promoting increased daily fluid intake. Other technologies, such as smart pill dispensers and hydration monitors, have potential applications in promoting behavioral change for stone disease but have yet to be evaluated for this purpose. SUMMARY There is a limited number of studies exploring technology as a means to promote and maintain behaviors that decrease urinary stone recurrence. Future research is needed to elucidate how to maximize the potential of these technologies and better understand which behavioral change techniques best promote habit formation for the prevention of stones.
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Affiliation(s)
- Leonid I. Aksenov
- Department of Urology, Duke University School of Medicine, Durham, NC
| | - Necole M. Streeper
- Department of Urology, Penn State Health Milton S. Hershey Medical Center, Hershey, PA
| | - Charles D. Scales
- Department of Urology, Duke University School of Medicine, Durham, NC
- Duke-Margolis Center for Health Policy, Duke University, Durham, NC
- Department Population Health Science and Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC
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Streeper NM, Fairbourn JD, Marks J, Thomaz E, Ram N, Conroy DE. Feasibility of Mini sip IT Behavioral Intervention to Increase Urine Volume in Patients With Kidney Stones. Urology 2023; 179:39-43. [PMID: 37393020 DOI: 10.1016/j.urology.2023.06.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 05/30/2023] [Accepted: 06/19/2023] [Indexed: 07/03/2023]
Abstract
OBJECTIVE To determine the feasibility and acceptability of mini sipIT, a context-sensitive reminder system that incorporates a connected water bottle and mobile app with text messaging, for kidney stone patients who have poor adherence to increasing fluid intake for prevention. METHODS Patients with a history of kidney stones and urine volume <2L/d participated in a 1-month single-group feasibility trial. Patients used a connected water bottle and received text message reminders when fluid intake goals weren't met. Perceptions of drinking behavior, intervention acceptability, and 24-hour urine volumes were obtained at baseline and 1-month. RESULTS Patients with a history of kidney stones were enrolled (n = 26, 77% female, age=50.4 ± 14.2years). Over 90% of patients used the bottle or app daily. Most patients perceived that mini sipIT intervention helped them to increase their fluid intake (85%) and reach their fluid intake goals (65%). There was a significant increase in average 24-hour urine volume after the 1-month intervention compared to baseline (2006.5 ± 980.8 mL vs 1352.7 ± 449.9 mL, t (25)= 3.66, P = .001, g= 0.78), with 73% of patients having higher 24-hour urine volumes at the end of the trial. CONCLUSION Mini sipIT behavioral intervention and outcome assessments are feasible for patients and may lead to significant increases in 24-hour urine volume. Digital tools in combination with behavioral science may improve adherence to fluid intake recommendations for kidney stone prevention, however, rigorous efficacy trials are necessary.
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Affiliation(s)
- Necole M Streeper
- Department of Urology, Penn State Health Milton S. Hershey Medical Center, Hershey, PA.
| | - Jason D Fairbourn
- Department of Urology, Penn State Health Milton S. Hershey Medical Center, Hershey, PA
| | - James Marks
- Department of Urology, Penn State Health Milton S. Hershey Medical Center, Hershey, PA
| | - Edison Thomaz
- Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX
| | - Nilam Ram
- Departments of Communication and Psychology, Stanford University, Stanford, CA
| | - David E Conroy
- Department of Kinesiology, Penn State University, State College, PA
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Stout TE, Lingeman JE, Krambeck AE, Humphreys MR, Zisman A, Elfering S, Large T, Dahm P, Borofsky M. A Randomized Trial Evaluating the Use of a Smart Water Bottle to Increase Fluid Intake in Stone Formers. J Ren Nutr 2022; 32:389-395. [DOI: 10.1053/j.jrn.2021.07.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 06/02/2021] [Accepted: 07/19/2021] [Indexed: 11/11/2022] Open
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Conroy DE, West AB, Brunke-Reese D, Thomaz E, Streeper NM. Just-in-time adaptive intervention to promote fluid consumption in patients with kidney stones. Health Psychol 2021; 39:1062-1069. [PMID: 33252930 DOI: 10.1037/hea0001032] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Kidney stones are painful and costly. Prevention guidelines emphasize a simple behavior change: increasing fluid intake and urine output. Unfortunately, adherence to those prevention guidelines is limited, and patients report forgetting or not being thirsty enough. This study evaluated the acceptability of using semiautomated tracking of fluid consumption to trigger just-in-time reminders to drink and increase the experienced automaticity of fluid intake. METHOD In a single-group trial, participants with a history of kidney stones (n = 31) used the sipIT digital tools (H2OPal connected water bottle, H2OPal mobile app for self-tracking, Fitbit smartwatch app for gesture detection) for 3 months. RESULTS The semiautomated monitoring system detected 46,654 drinking events. From baseline to 1-month follow-up, the experienced automaticity of fluid intake increased significantly (d = 0.50) and remained elevated at 3-month follow-up (d = 0.64). A major barrier to adherence (lack of thirst) decreased from baseline to follow-ups. Retention rates and participant feedback indicated that this digital tool was acceptable to patients. CONCLUSION Semiautomated tracking of fluid consumption can be used to trigger just-in-time reminders. Based on this demonstration, the sipIT tools are ready for testing in a rigorous Phase II trial to evaluate efficacy for increasing fluid consumption and urine output as recommended for preventing the recurrence of kidney stones. (PsycInfo Database Record (c) 2020 APA, all rights reserved).
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Scales CD, Desai AC, Harper JD, Lai HH, Maalouf NM, Reese PP, Tasian GE, Al-Khalidi HR, Kirkali Z, Wessells H. Prevention of Urinary Stones With Hydration (PUSH): Design and Rationale of a Clinical Trial. Am J Kidney Dis 2020; 77:898-906.e1. [PMID: 33212205 DOI: 10.1053/j.ajkd.2020.09.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 09/15/2020] [Indexed: 11/11/2022]
Abstract
RATIONALE & OBJECTIVE Although maintaining high fluid intake is an effective low-risk intervention for the secondary prevention of urinary stone disease, many patients with stones do not increase their fluid intake. STUDY DESIGN We describe the rationale and design of the Prevention of Urinary Stones With Hydration (PUSH) Study, a randomized trial of a multicomponent behavioral intervention program to increase and maintain high fluid intake. Participants are randomly assigned (1:1 ratio) to the intervention or control arm. The target sample size is 1,642 participants. SETTING & PARTICIPANTS Adults and adolescents 12 years and older with a symptomatic stone history and low urine volume are eligible. Exclusion criteria include infectious or monogenic causes of urinary stone disease and comorbid conditions precluding increased fluid intake. INTERVENTIONS All participants receive usual care and a smart water bottle with smartphone application. Participants in the intervention arm receive a fluid intake prescription and an adaptive program of behavioral interventions, including financial incentives, structured problem solving, and other automated adherence interventions. Control arm participants receive guideline-based fluid instructions. OUTCOMES The primary end point is recurrence of a symptomatic stone during 24 months of follow-up. Secondary end points include changes in radiographic stone burden, 24-hour urine output, and urinary symptoms. LIMITATIONS Periodic 24-hour urine volumes may not fully reflect daily behavior. CONCLUSIONS With its highly novel features, the PUSH Study will address an important health care problem. FUNDING National Institute of Diabetes and Digestive and Kidney Diseases. TRIAL REGISTRATION Registered at ClinicalTrials.gov with study number NCT03244189.
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Affiliation(s)
- Charles D Scales
- Urologic Surgery and Population Health Science, Duke Surgical Center for Outcomes Research, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC.
| | - Alana C Desai
- Division of Urologic Surgery, Department of Surgery, Washington University School of Medicine, St Louis, MO
| | - Jonathan D Harper
- Department of Urology, University of Washington School of Medicine, Seattle, WA
| | - H Henry Lai
- Division of Urologic Surgery, Department of Surgery, Washington University School of Medicine, St Louis, MO
| | - Naim M Maalouf
- Department of Internal Medicine and Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX
| | - Peter P Reese
- Renal-Electrolyte and Hypertension Division, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA; Department of Biostatistics, Epidemiology, and Informatics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA
| | - Gregory E Tasian
- Department of Biostatistics, Epidemiology, and Informatics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA; Division of Pediatric Urology, Department of Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA
| | - Hussein R Al-Khalidi
- Department of Biostatistics and Bioinformatics, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC
| | - Ziya Kirkali
- National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD
| | - Hunter Wessells
- Department of Urology, University of Washington School of Medicine, Seattle, WA
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Association Between Daily Water Intake and 24-hour Urine Volume Among Adolescents With Kidney Stones. Urology 2020; 140:150-154. [PMID: 32004558 DOI: 10.1016/j.urology.2020.01.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 01/15/2020] [Accepted: 01/20/2020] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To determine the association between daily water intake and 24-hour urine volume among adolescents with nephrolithiasis in order to estimate a "fluid prescription," the additional water intake needed to increase urine volume to a target goal. METHODS We conducted a secondary analysis of an ecological momentary assessment study that prospectively measured daily water intake of 25 adolescents with nephrolithiasis over 7 days. We identified 24-hour urine volumes obtained for clinical care within 12 months of water intake assessment. A linear regression model was fit to estimate the magnitude of the association between daily water intake and 24-hour urine volume, adjusting for age, sex, race, and daily temperature. RESULTS Twenty-two participants completed fifty-seven 24-hour urine collections within 12 months of the study period. Median daily water intake was 1.4 L (IQR 0.67-1.94). Median 24-hour urine volume was 2.01 L (IQR 1.20-2.73). A 1 L increase in daily water intake was associated with a 710 mL increase in 24-hour urine output (95%CI 0.55-0.87). Using the model output, the equation was generated to estimate the additional fluid intake needed fluid prescription (FP) to produce the desired increase in urine output (dUOP): FP = dUOP/0.71. CONCLUSION The FP equation (FP = dUOP)/0.71), which reflects the relationship between water intake and urine volume, could be used to help adolescents with nephrolithiasis achieve urine output goals to decrease stone recurrence.
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Tasian GE, Ross M, Song L, Audrain-McGovern J, Wiebe D, Warner SG, Henderson B, Patel A, Furth SL. Ecological Momentary Assessment of Factors Associated with Water Intake among Adolescents with Kidney Stone Disease. J Urol 2019; 201:606-614. [PMID: 30076905 DOI: 10.1016/j.juro.2018.07.064] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE Maintaining high water intake decreases kidney stone recurrence but is difficult to do. Strategies to reduce stone recurrence among adolescents are lacking. We conducted an ecological momentary assessment study to identify factors associated with water intake in adolescents with nephrolithiasis. MATERIALS AND METHODS The study population consisted of 15 female and 10 male patients 12 to 18 years old with at least 1 prior kidney stone. For 7 days participants used "smart" bottles to self-monitor water intake and received questionnaires randomly 4 times daily, which were completed in real time on mobile devices. The questionnaires ascertained awareness of water intake volume, awareness of water intake goals, perceived need to drink, access to water, alternative beverage consumption and attitudes toward bathrooms. Linear mixed effects models were fit to estimate the association between momentary responses and daily water intake. RESULTS During 175 person-days 595 assessments (85%) were completed. Median daily water intake was 1,304 ml (IQR 848-1,832) and 20% of participants met their intake goal for 4 days or more. Unawareness of water intake volume was associated with drinking 690 ml less water per day (p = 0.04). A strong self-perceived need to drink more was associated with drinking 1,954 ml less water each day compared to no self-perceived need to drink more (p <0.01). Unawareness of intake goals was weakly associated with drinking 1,129 ml less water each day (p = 0.1). Access to water, alternative beverage consumption and bathroom aversion were not associated with water intake. CONCLUSIONS Unawareness of water volume consumed and low responsiveness to perceived need to drink more were associated with low water intake. Interventions that help adolescents recognize when and identify how to increase water intake may be effective in decreasing stone recurrence.
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Affiliation(s)
- Gregory E Tasian
- Department of Surgery, Division of Pediatric Urology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Center for Pediatric Clinical Effectiveness, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Department of Surgery, Division of Urology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Biostatistics, Epidemiology and Informatics, Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Michelle Ross
- Department of Biostatistics, Epidemiology and Informatics, Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Lihai Song
- Center for Pediatric Clinical Effectiveness, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Janet Audrain-McGovern
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Douglas Wiebe
- Department of Biostatistics, Epidemiology and Informatics, Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Steven G Warner
- Department of Surgery, Division of Pediatric Urology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Brittney Henderson
- Department of Surgery, Division of Pediatric Urology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Anisha Patel
- Department of Pediatrics, Stanford University, Stanford, California
| | - Susan L Furth
- Division of Nephrology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Department of Biostatistics, Epidemiology and Informatics, Center for Clinical Epidemiology and Biostatistics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
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Menezes CJ, Worcester EM, Coe FL, Asplin J, Bergsland KJ, Ko B. Mechanisms for falling urine pH with age in stone formers. Am J Physiol Renal Physiol 2019; 317:F65-F72. [PMID: 31017011 DOI: 10.1152/ajprenal.00066.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
One of the main functions of the kidney is to excrete an acid load derived from both dietary and endogenous sources, thus maintaining the pH of other fluids in the body. Urine pH is also of particular interest in stone formers, since it determines the presence of either calcium phosphate or uric acid content in stones. Others have noted in epidemiological studies a rise in incidence of low pH-dependent uric acid stones with age, coinciding with a decrease in the incidence of high pH-dependent phosphate stones. Taken together, these trends are suggestive of a longitudinal decline in urine pH in stone-forming patients, and, if true, this could explain the observed trends in stone incidence. We studied 7,891 stone formers, all of whom collected a 24-h urine sample and matching serum. Multivariate modeling revealed that urine pH did indeed fall with age and particularly between the ages of 20 and 50 yr old in both men and women. We sought to explain this trend through the inclusion of traditionally understood determinants of urine pH such as urinary buffers, estimates of glomerular filtration, and dietary acid load, but these, taken together, accounted for but a small fraction of the pH fall. Gastrointestinal anion absorption was the strongest predictor of urine pH in all age groups, as we have previously reported in middle-aged normal men and women. However, we found that, despite a decreasing urine pH, gastrointestinal anion absorption increased monotonically with age. In fact, after adjustment for gastrointestinal anion absorption, urine pH declined more markedly, suggesting that bicarbonate-producing anion absorption is regulated in a manner that offsets the decline of urine pH.
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Affiliation(s)
- Cameron J Menezes
- Department of Medicine, University of Chicago Medicine , Chicago, Illinois
| | - Elaine M Worcester
- Department of Medicine, University of Chicago Medicine , Chicago, Illinois
| | - Fredric L Coe
- Department of Medicine, University of Chicago Medicine , Chicago, Illinois
| | - John Asplin
- Litholink, Laboratory Corporation of America Holdings , Chicago, Illinois
| | | | - Benjamin Ko
- Department of Medicine, University of Chicago Medicine , Chicago, Illinois
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Hoy NY, Dean NS, Wu J, Wollin TA, De SK. Impact of LUTS on urine volume in stone formers The impact of lower urinary tract symptomatology on urine volumes in stone formers. Can Urol Assoc J 2018; 13:256-259. [PMID: 30526800 DOI: 10.5489/cuaj.5530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
INTRODUCTION We aimed to determine if there is a correlation between International Prostate Symptom scores (IPSS) and 24-hour urine collection volumes, as patients experiencing lower urinary tract symptoms (LUTS) may have impaired ability to increase fluid intake for stone prevention. METHODS We conducted a single-centre, retrospective review was performed of stone-formers presenting from 2014-2016. Inclusion criteria were completion of an IPSS questionnaire and a 24-hour urine collection. Exclusion criteria included symptomatic stone or urinary tract infection at time of IPSS completion, inadequate 24-hour collection, or incomplete IPSS questionnaire. RESULTS A total of 131 patients met inclusion criteria. Stratification by IPSS severity into mild (0-7), moderate (8-19), and severe (20-35) yielded groups of n=96, 28, and 7, respectively. Linear regression modelling did not reveal a correlation between IPSS score and volume (p=0.10). When compared to those with adequate urine volumes (>2 L/day, n=65), low-volume patients (<1 L/day, n=10) had a significantly higher total IPSS (11.7 vs. 6.1; p=0.036). These groups showed significant differences in their responses to questions about incomplete emptying (p=0.031), intermittency (p=0.011), and stranguria (p=0.0020), with higher scores noted in the low urine output group. CONCLUSIONS This study is the first to examine the correlation between IPSS and 24-hour urine volume. Though our data does not show a linear relationship between urine output and IPSS, those with lower urine volumes appear to have worse self-reported voiding symptoms when compared to those with adequate volumes (>2 L/day) for stone prevention. The overall number of patients in our study is relatively small, which may account for the lack of a relationship between IPSS and 24-hour urine volumes.
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Affiliation(s)
- Nathan Y Hoy
- Division of Urology, University of Alberta, Edmonton, AB, Canada
| | - Nick S Dean
- Division of Urology, University of Alberta, Edmonton, AB, Canada
| | - Jeremy Wu
- Division of Urology, University of Alberta, Edmonton, AB, Canada
| | - Timothy A Wollin
- Division of Urology, University of Alberta, Edmonton, AB, Canada
| | - Shubha K De
- Division of Urology, University of Alberta, Edmonton, AB, Canada
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Bergsland KJ, Coe FL, Parks JH, Asplin JR, Worcester EM. Evidence for a role of PDZ domain-containing proteins to mediate hypophosphatemia in calcium stone formers. Nephrol Dial Transplant 2018; 33:759-770. [PMID: 29126251 DOI: 10.1093/ndt/gfx284] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 08/29/2017] [Indexed: 01/26/2023] Open
Abstract
Background Hypophosphatemia (HYP) is common among calcium stone formers (SFs) and in rare cases is associated with mutations in sodium-phosphate cotransporters or in Na+/H+ exchanger regulatory factor 1 (NHERF1), but the majority of cases are unexplained. We hypothesized that reduced sodium-phosphate cotransporter activity mediated via NHERF1 or a similar PDZ domain-containing protein, causes HYP. If so, other transport activities controlled by NHERF1, such as NHE3 and URAT1, might be reduced in HYP. Methods To test this idea, we analyzed two large but separate sets of 24-h urine samples and paired serums of 2700 SFs from the University of Chicago and 11 073 SFs from Litholink, a national laboratory. Patients were divided into quintiles based on serum phosphate. Results Males were more common in the lowest phosphate tiles in both datasets. Phosphate excretion did not vary across the quintiles, excluding diet as a cause of HYP. Tubule maximum (Tm) phosphate per unit glomerular filtration rate decreased and fractional excretion increased with decreasing phosphate quintiles, indicating reduced tubule phosphate reabsorption was responsible for HYP. Urine pH and serum chloride increased with decreasing serum phosphate, suggesting a coordinate change in NHE3 activity. Serum uric acid and Tm uric acid decreased significantly with decreasing serum phosphate, while uric acid excretion did not vary. Conclusion. HYP in SFs results from decreased tubule phosphate reabsorption and, being associated with related changes in other proximal tubule transporters, may arise from alterations in or signaling to PDZ-containing proteins.
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Affiliation(s)
| | - Fredric L Coe
- Department of Medicine, University of Chicago, Chicago, IL, USA
| | - Joan H Parks
- Department of Medicine, University of Chicago, Chicago, IL, USA
| | - John R Asplin
- Litholink Corporation, Laboratory Corporation of America Holdings, Chicago, IL, USA
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Effects of small molecules water that may retard kidney stone formation. Int Urol Nephrol 2017; 50:225-230. [PMID: 29236240 DOI: 10.1007/s11255-017-1769-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 12/08/2017] [Indexed: 10/18/2022]
Abstract
PURPOSE Water intake is important for preventing kidney stones. Small molecules water is a more active restructured water under magnetic field. Here, we studied the relation between small molecules water and crystal formation in the rat kidney. MATERIALS The small molecules water was prepared by a water machine providing a 0.8-T magnetic field. Calcium oxalate crystals were induced by 0.75% EG (ethylene glycol) in male Sprague-Dawley rats by drinking small molecules water and plain water for up to 6 weeks, respectively. Urinary ions were assayed. Osteopontin mRNA expression and urinary LDH were detected. Crystals were observed using a light microscope and a polarizing microscope. RESULTS A significantly reduced urinary calcium and phosphorus excretion occurred in the 2nd and the 4th week after treatment of small molecules water. Crystals were initially detected in 40% of the experimental rats in the small molecules water group at the 6th week, later than the control group in which crystals were detected in 60% of rats at the 4th week. After 6 weeks of treatment, crystals were observed to form in renal cortex, medulla and papilla in the control group, whereas only to form in renal medulla and papilla in the small molecules water group. OPN mRNA expression significantly increased earlier in the 2nd week after treatment of the small molecules water compared to the control (P = 0.016). CONCLUSIONS Small molecules water may retard crystal formation, reduce urinary calcium and phosphorus excretion and promote earlier OPN mRNA expression in the rat kidney.
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Abstract
Nephrolithiasis is highly prevalent across all demographic groups in the Western world and beyond, and its incidence rates are rising. In addition to the morbidity of the acute event, stone disease often becomes a lifelong problem that requires preventative therapy to diminish ongoing morbidity. Across the majority of stone types, increased fluid intake and targeted dietary modifications are mainstays of therapy. Specific dietary interventions associated with reduced calcium stone risk include adequate dietary calcium intake and restriction of sodium, protein, and oxalate intake, among others. Pharmaceutical therapy may be required if lifestyle changes are insufficient to minimize risk of stone recurrence, and must be targeted to the specific metabolic abnormalities portending risk for a given patient. Therapeutic options for idiopathic calcium stone disease include thiazides, citrate salts, and uric acid-lowering agents. Alkali salts are also the treatment of choice for uric acid stone disease. Management of struvite stone disease is largely surgical, but acetohydroxamic acid is a proven second line therapy. Cystinuria requires lifestyle modifications and may call for thiol-binding agents. Significant heterogeneity of the clinical population with stone disease has previously limited opportunities for large randomized controlled trials. However, as clinical phenotypes and genotypes are increasingly clarified, there are mounting opportunities for targeted randomized controlled trials in stone prevention. In the meantime, the currently available evidence for both lifestyle and pharmacologic interventions is reviewed herein.
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Affiliation(s)
- Anna L Zisman
- Section of Nephrology, Department of Medicine, University of Chicago, Chicago, Illinois
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15
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Chua TXW, Prasad NS, Rangan GK, Allman-Farinelli M, Rangan AM. A systematic review to determine the most effective interventions to increase water intake. Nephrology (Carlton) 2017; 21:860-9. [PMID: 26599520 DOI: 10.1111/nep.12675] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 11/17/2015] [Accepted: 11/18/2015] [Indexed: 01/07/2023]
Abstract
BACKGROUND Maintaining adequate fluid intake has been hypothesized to be beneficial for the progression of chronic kidney disease (CKD). The aim of this study was to undertake a systematic review to determine the most effective interventions to increase water intake. METHODS Six electronic databases were searched from 1910 until March 2015 in the English language. Additional sources through hand-searches, expert recommendations and reviews were checked. Intervention studies increasing water intake in adults through non-pharmacological methods were eligible for inclusion. The quality of included studies was assessed. RESULTS A total of 950 studies were found of which 16 met the inclusion criteria. Eight studies were randomized controlled trials, and seven studies spanned 6 months or longer. The study populations varied and included patients with recurrent nephrolithiasis (n = 6), autosomal dominant polycystic kidney disease (n = 3), CKD (n = 1), urinary tract infection (n = 1) and other miscellaneous conditions (n = 5). The quality of the studies was mostly neutral (63%) with no studies of high quality. Interventions ranged from instruction alone to self-monitoring tools, providing water bottles and counselling and education. Most interventions successfully increased water intake with 13 studies reporting an increase of at least 500 mL. The most effective strategies were instruction and self-monitoring using urine dipstick or 24 h urine volume. CONCLUSION All interventions carried out in the studies succeeded in increasing water intake, with none leading to decreases in intake, and these could be implemented in potential clinical trials in CKD. However, more high quality long-term intervention studies are required to further validate findings.
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Affiliation(s)
- Teresa X W Chua
- School of Molecular Bioscience, Charles Perkins Centre, The University of Sydney, Sydney, Australia.,Centre for Transplant and Renal Research, Westmead Institute for Medical Research, University of Sydney, Sydney, Australia
| | - Neha S Prasad
- School of Molecular Bioscience, Charles Perkins Centre, The University of Sydney, Sydney, Australia.,Centre for Transplant and Renal Research, Westmead Institute for Medical Research, University of Sydney, Sydney, Australia
| | - Gopala K Rangan
- Centre for Transplant and Renal Research, Westmead Institute for Medical Research, University of Sydney, Sydney, Australia.,Department of Renal Medicine, Westmead Hospital, Western Sydney Local Health District, Sydney, Australia
| | | | - Anna M Rangan
- School of Molecular Bioscience, Charles Perkins Centre, The University of Sydney, Sydney, Australia.
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16
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Abstract
Adequate fluid intake can be dually defined as a volume of fluid (from water, beverages, and food) sufficient to replace water losses and provide for solute excretion. A wide range of fluid intakes are compatible with euhydration, whereby total body water varies narrowly from day to day by 600 to 900 mL (<1% body mass). One measure of fluid intake adequacy involves enough fluid to prevent meaningful body water deficits outside this euhydration range (i.e., dehydration). Another measure of fluid intake adequacy involves enough fluid to balance the renal solute load, which can vary widely inside the euhydration range. The subtle but important distinction between the 2 types of adequacy may explain some of the ambiguity surrounding the efficacy of hydration status markers. Both perspectives of fluid intake adequacy are discussed in detail and a simple tool is reviewed that may help healthy, active, low-risk populations answer the question, "Am I drinking enough?" Key Teaching Points • Adequate fluid intake can be dually defined as a volume of fluid (from water, beverages, and food) sufficient to replace water losses and provide for solute excretion. • Fluid needs can differ greatly among individuals due to variation in the factors that influence both water loss and solute balance; thus, adequacy is consistent with a wide range of fluid intakes and is better gauged using hydration assessment methods. • Adequacy of fluid intake for replacing meaningful water losses (dehydration) can be assessed simply, inexpensively, and with reasonable fidelity among healthy, active, low-risk individuals. • Adequacy of fluid intake for solute excretion per se can also be assessed among individuals but is more difficult to define and less practical to measure.
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Affiliation(s)
- Samuel N Cheuvront
- a U.S. Army Research Institute of Environmental Medicine , Natick , Massachusetts
| | - Robert W Kenefick
- a U.S. Army Research Institute of Environmental Medicine , Natick , Massachusetts
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17
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Nouvenne A, Ticinesi A, Allegri F, Guerra A, Guida L, Morelli I, Borghi L, Meschi T. Twenty-five years of idiopathic calcium nephrolithiasis: has anything changed? ACTA ACUST UNITED AC 2013; 52:337-44. [DOI: 10.1515/cclm-2013-0618] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Accepted: 09/17/2013] [Indexed: 12/12/2022]
Abstract
Abstract
Idiopathic calcium nephrolithiasis (ICN) is a disease whose prevalence is rising. Our aim was to assess whether lifestyle indicators and habits of calcium stone formers in Italy have changed over the last 25 years, trying to establish a connection with the diffusion of Internet access. Therefore we examined the database of the Stone Clinic of Parma University Hospital and extracted 1952 (1192 M, 760 F) patients with ICN who underwent a full clinical and laboratory evaluation from 1986 to 2010. Laboratory evaluation included data on urinary 24-h volume, pH, sodium, potassium, chloride, calcium, phosphate, uric acid, magnesium, oxalate, and citrate. Patients were split in three groups on a chronological basis, according to official EUROSTAT-ISTAT data of Internet connection among families in Italy: Group 1, pre-Internet era (1986–1998, 853 patients); Group 2, narrow-band era (1999–2004, 467 patients); Group 3, broad-band era (2005–2010, 632 patients). Over the time we found a significant increase in water intake (1.37 vs. 1.78 L in men and 1.21 vs. 1.55 L in women, Group 1 vs. Group 3, p-trend<0.001) and a decrease in urinary sodium and chloride for both genders and calcium and magnesium only for males, while females experienced a slight increase in oxalate excretion. Supersaturation indexes for calcium and uric acid stones dramatically fell for both genders. The percentage of stone formers performing physical activity significantly rise (41% Group 3 vs. 8% Group 1, p<0.001) and we also found a trend of reduction in mean blood pressure. Therefore, the lifestyle of Italian idiopathic calcium stone formers has changed over the last 25 years, and the rising Internet access may have played a great role in driving this change.
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Affiliation(s)
- Antonio Nouvenne
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy
- Internal Medicine and Critical Subacute Care Unit, University Hospital of Parma, Parma, Italy
| | - Andrea Ticinesi
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy
| | - Franca Allegri
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy
| | - Angela Guerra
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy
| | - Loredana Guida
- Internal Medicine and Critical Subacute Care Unit, University Hospital of Parma, Parma, Italy
| | - Ilaria Morelli
- Internal Medicine and Critical Subacute Care Unit, University Hospital of Parma, Parma, Italy
| | - Loris Borghi
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy
| | - Tiziana Meschi
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy
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18
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Sawyer MD, Anderson CB, Viprakasit DP, Dietrich MS, Herrell SD, Miller NL. An individualized weight-based goal urine volume model significantly improves expected calcium concentrations relative to a 2-L goal urine volume. Urolithiasis 2013; 41:403-9. [PMID: 23857331 DOI: 10.1007/s00240-013-0573-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 05/21/2013] [Indexed: 11/27/2022]
Abstract
Increased urinary volume decreases recurrence rates of nephrolithiasis. Current recommendations for goal volumes are not adjusted to reflect individual risk factors, such as obesity. Our intent was to develop and evaluate a goal urine volume for stone prevention based on predictive calcium modeling. Stone formers with a 24-h urine study (6/2001-9/2010) were identified. Patients with inadequate collections or non-calcium stones were excluded. Multivariate and univariate predictive models for daily calcium were evaluated and a univariate (weight) model was selected. A target calcium concentration constant (2.5 mM) was determined from current recommendations. Individualized weight-based goal urine volumes (WGUV) were calculated. Measured calcium concentration and expected calcium concentrations using a 2-L goal volume and WGUV were compared. 185 of 399 patients met inclusion criteria. Body weight was a strong predictor of calcium excretion in each model (p < 0.0001). While a 2-L goal urine volume would be expected to improve mean calcium concentrations for the cohort from 3.53 to 2.96 mM, the benefit is unequal between subsets with nearly twofold expected concentration for the highest weight quartile (3.98 vs. 2.10 mM) and higher expected concentration for males (3.35 vs. 2.59 mM). By contrast, a WGUV model improves expected concentrations for all subsets to <2.9 mM and the overall cohort to 2.50 mM. This study demonstrates a strong relationship between body weight and urinary calcium excretion in stone formers. We introduce the novel concept of individualized goal urine output using statistical modeling, which may be preferable to current recommendations.
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Affiliation(s)
- Mark D Sawyer
- Department of Urologic Surgery, Vanderbilt University Medical Center, A-1302, MCN, Nashville, TN, 37232-2765, USA,
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19
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Khorami MH, Hashemi R, Bagherian-Sararoudi R, Sichani MM, Tadayon F, Shahdoost AA, Arezegar SH. The assessment of 24 24-h urine volume by measurement of urine specific gravity with dipstick in adults with nephrolithiasis. Adv Biomed Res 2012; 1:86. [PMID: 23946934 PMCID: PMC3724327 DOI: 10.4103/2277-9175.105168] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2012] [Accepted: 06/19/2012] [Indexed: 11/23/2022] Open
Abstract
Background: Nephrolithiasis is a recurrent disease, and one of the most effective methods for prevention of stone recurrence is increasing the urine output (>2 L/day), but it is difficult to achieve it. The aim of this study was to evaluate the effect of behavioral intervention by measurement of urine specific gravity using dipstick on 24-h urine volume in first renal stone patients. Materials and Methods: In this prospective randomize clinical study, 80 adult patients with history of first renal stone were included. Patients were divided into two groups with 40 patients in each group. We explained the importance of high fluid intake and high urine volume in the prevention of renal stones for all patients. Group A patients were trained to measure 24-h urine volume every 15 days, and group B patients were trained to keep urine specific gravity below 1.010 by using dipstick. We measured 24-h urine volume in each group before intervention, and at 3 months and 6 months after intervention and compared them. Results: There were no significant differences between the two groups in 24-h urine volume before intervention (P = 0.41), but it was significant 3 months (P = 0.01) and 6 months (P = 0.01) after intervention. Patients’ compliance was 20% in group A and 90% in group B (P < 0.05). Conclusion: The use of behavioral modification with dipstick is an effective method for control and maintenance of optimal urine volume, and it has resulted in more patient compliance for drinking water and is more effective for prevention of renal stone.
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Affiliation(s)
- Mohamad Hatef Khorami
- Department of Urology, Isfahan University of medical science, Alzahra hospital, Isfahan, Iran
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20
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Abstract
Nephrolithiasis is a prevalent and costly condition with high recurrence rate. A medical evaluation to identify abnormalities responsible for nephrolithiasis and guide subsequent therapy has been advocated to reduce the risk of stone recurrence. The evaluation of kidney stone formers generally comprises an extensive medical history to identify metabolic, environmental, dietary and/or genetic factors contributing to stone formation. Imaging studies are utilized to evaluate and follow stone burden. Laboratory studies including stone composition analysis and serum and urinary chemistries are commonly obtained to further assess for any underlying systemic disorders, to detect environmental and metabolic processes contributing to stone disease, and to guide initial and follow-up dietary and pharmacological therapy. The nature and extent of such an evaluation is discussed in this review article.
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Affiliation(s)
- Naim Maalouf
- Department of Internal Medicine and Charles and Jane Pak Center for Mineral Metabolism, University of Texas Southwestern Medical Center Dallas, TX, U.S.A
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21
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Abstract
Practical relevance Calcium oxalate (CaOx) containing stones are among the most common of the urinary tract stones identified in cats. Risk factors Risk factors for CaOx stone formation include such things as breed, gender and diet; stress and obesity have also been hypothesized to be risk factors for this disease. Management approach A tailored, individual management strategy for preventing CaOx stone recurrence is important and should include addressing the diet, environment and any other comorbid conditions present. Increasing the cat's moisture intake is one of the key mechanisms for preventing recurrence. Clinical challenges CaOx ureterolithiasis has emerged as a difficult and sometimes life-threatening problem for cats. In those cats where stones are found incidentally, periodic monitoring may be required to assess for disease progression. Interventional procedures such as ureteral stent placements are now increasingly being performed for recurrent cases or those with larger stone burdens. Periodic radiographs for more severe cases and frequent client communication can help ensure successful outcomes for cats with lower and upper CaOx stone disease. Evidence base Limited evidence-based studies are published regarding management of feline upper and lower urinary tract CaOx stone disease, making this a difficult condition to manage in some cats. Studies designed to evaluate the relationship to dietary modifications, medical management, stress, obesity and surgical techniques are warranted in cats with upper and lower urinary tract CaOx stones.
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22
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Renkema KY, Bindels RJM, Hoenderop JGJ. Role of the calcium-sensing receptor in reducing the risk for calcium stones. Clin J Am Soc Nephrol 2011; 6:2076-82. [PMID: 21784822 DOI: 10.2215/cjn.00480111] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The tight control of blood Ca2+ levels within a narrow range is essential for the performance of vital physiologic functions. Muscle contraction, neuronal excitation, and intracellular signaling processes acquisitively require Ca2+. It is the concerted action of intestine, bone, and kidney that controls the Ca2+ balance through the regulation of intestinal absorption, bone (de)mineralization, and renal excretion of Ca2+, respectively. Along the nephron, fine-tuning of blood Ca2+ levels takes place by Ca2+ reabsorption. The calciotropic hormones regulate Ca2+ transport processes, leading to whole-body Ca2+ homeostasis and, importantly, preserving a constant Ca2+ concentration in the blood. Defects in renal Ca2+ handling can lead to hypercalciuria, consecutive kidney stone formation, and obstructive nephropathy. Here we give an overview of the key players involved in normal Ca2+ management and describe the in-depth investigations on a renal hypercalciuric model of disease, the Trpv5 knockout mouse, which naturally displays molecular adaptations that prevent Ca2+ precipitation in the kidney.
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Affiliation(s)
- Kirsten Y Renkema
- Department of Physiology (286), Radboud University Nijmegen Medical Centre (RUNMC), P.O. Box 9101, 6500 HB Nijmegen, The Netherlands
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Bankir L, Bichet DG, Bouby N. Vasopressin V2 receptors, ENaC, and sodium reabsorption: a risk factor for hypertension? Am J Physiol Renal Physiol 2010; 299:F917-28. [PMID: 20826569 DOI: 10.1152/ajprenal.00413.2010] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Excessive sodium reabsorption by the kidney has long been known to participate in the pathogenesis of some forms of hypertension. In the kidney, the final control of NaCl reabsorption takes place in the distal nephron through the amiloride-sensitive epithelial sodium channel (ENaC). Liddle's syndrome, an inherited form of hypertension due to gain-of-function mutations in the genes coding for ENaC subunits, has demonstrated the key role of this channel in the sodium balance. Although aldosterone is classically thought to be the main hormone regulating ENaC activity, several studies in animal models and in humans highlight the important effect of vasopressin on ENaC regulation and sodium transport. This review summarizes the effect of vasopressin V2 receptor stimulation on ENaC activity and sodium excretion in vivo. Moreover, we report the experimental and clinical data demonstrating the role of renal ENaC in water conservation at the expense of a reduced ability to excrete sodium. Acute administration of the selective V2 receptor agonist dDAVP not only increases urine osmolality and reduces urine flow rate but also reduces sodium excretion in rats and humans. Chronic V2 receptor stimulation increases blood pressure in rats, and a significant correlation was found between blood pressure and urine concentration in healthy humans. This led us to discuss how excessive vasopressin-dependent ENaC stimulation could be a risk factor for sodium retention and resulting increase in blood pressure.
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Affiliation(s)
- Lise Bankir
- INSERM U872, Equipe 2, Centre de Recherches des Cordeliers, 15 rue de l'Ecole de Médecine, 75006 Paris, France
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24
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Torres VE, Bankir L, Grantham JJ. A case for water in the treatment of polycystic kidney disease. Clin J Am Soc Nephrol 2009; 4:1140-50. [PMID: 19443627 DOI: 10.2215/cjn.00790209] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Autosomal dominant polycystic disease (ADPKD) is an inherited disorder characterized by the development within renal tubules of innumerable cysts that progressively expand to cause renal insufficiency. Tubule cell proliferation and transepithelial fluid secretion combine to enlarge renal cysts, and 3'-5'-cyclic adenosine monophosphate (cAMP) stimulates that growth. The antidiuretic hormone, arginine vasopressin (AVP), operates continuously in ADPKD patients to stimulate the formation of cAMP, thereby contributing to cyst and kidney enlargement and renal dysfunction. Studies in animal models of ADPKD provide convincing evidence that blocking the action of AVP dramatically ameliorates the disease process. In the current analysis, the authors reason that increasing the amount of solute-free water drunk evenly throughout the day in patients with ADPKD and normal renal function will decrease plasma AVP concentrations and mitigate the action of cAMP on the renal cysts. Potential pitfalls of increasing fluid intake in ADPKD patients are considered, and suggestions for how physicians may prudently implement this therapy are offered.
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Affiliation(s)
- Vicente E Torres
- Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA.
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25
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Goodman JW, Asplin JR, Goldfarb DS. Effect of two sports drinks on urinary lithogenicity. ACTA ACUST UNITED AC 2008; 37:41-6. [DOI: 10.1007/s00240-008-0166-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Accepted: 11/25/2008] [Indexed: 11/28/2022]
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Crowell E, Wang G, Cox J, Platz CP, Geng L. Correlation coefficient mapping in fluorescence spectroscopy: tissue classification for cancer detection. Anal Chem 2007; 77:1368-75. [PMID: 15732920 DOI: 10.1021/ac049074+] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Correlation coefficient mapping has been applied to intrinsic fluorescence spectra of colonic tissue for the purpose of cancer diagnosis. Fluorescence emission spectra were collected of 57 colonic tissue sites in a range of 4 physiological conditions: normal (29), hyperplastic (2), adenomatous (5), and cancerous tissues (21). The sample-sample correlation was used to examine the ability of correlation coefficient mapping to determine tissue disease state. The correlation coefficient map indicates two main categories of samples. These categories were found to relate to disease states of the tissue. Sensitivity, selectivity, predictive value positive, and predictive value negative for differentiation between normal tissue and all other categories were all above 92%. This was found to be similar to, or higher than, tissue classification using existing methods of data reduction. Wavelength-wavelength correlation among the samples highlights areas of importance for tissue classification. The two-dimensional correlation map reveals absorption by NADH and hemoglobin in the samples as negative correlation, an effect not obvious from the one-dimensional fluorescence spectra alone. The integrity of tissue was examined in a time series of spectra of a single tissue sample taken after tissue resection. The wavelength-wavelength correlation coefficient map shows the areas of significance for each fluorophore and their relation to each other. NADH displays negative correlation to collagen and FAD, from the absorption of emission or fluorescence resonance energy transfer. The wavelength-wavelength correlation map for the decay set also clearly shows that there are only three fluorophores of importance in the samples, by the well-defined pattern of the map. The sample-sample correlation coefficient map reveals the changes over time and their impact on tissue classification. Correlation coefficient mapping proves to be an effective method for sample classification and cancer detection.
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Affiliation(s)
- Ed Crowell
- Department of Chemistry, the Optical Science and Technology Center, and the Center for Biocatalysis and Bioprocessing, University of Iowa, Iowa City, Iowa 52242, USA
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27
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Abstract
About 5% of American women and 12% of men will develop a kidney stone at some time in their life, and prevalence has been rising in both sexes. Approximately 80% of stones are composed of calcium oxalate (CaOx) and calcium phosphate (CaP); 10% of struvite (magnesium ammonium phosphate produced during infection with bacteria that possess the enzyme urease), 9% of uric acid (UA); and the remaining 1% are composed of cystine or ammonium acid urate or are diagnosed as drug-related stones. Stones ultimately arise because of an unwanted phase change of these substances from liquid to solid state. Here we focus on the mechanisms of pathogenesis involved in CaOx, CaP, UA, and cystine stone formation, including recent developments in our understanding of related changes in human kidney tissue and of underlying genetic causes, in addition to current therapeutics.
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Affiliation(s)
- Fredric L Coe
- Renal Section, University of Chicago, Chicago, Illinois 60637, USA.
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28
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Parks JH, Worcester EM, Coe FL, Evan AP, Lingeman JE. Clinical implications of abundant calcium phosphate in routinely analyzed kidney stones. Kidney Int 2004; 66:777-85. [PMID: 15253733 DOI: 10.1111/j.1523-1755.2004.00803.x] [Citation(s) in RCA: 151] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND To better portray the clinical phenotype of kidney stone patients with high calcium phosphate (CaP) stone abundance, we present here clinical and laboratory findings of large numbers of stone formers (SF) with stone CaP ranging from 0% to 100%. Our purpose was to inform clinicians and highlight areas that seem to deserve further research. METHODS We calculated average percent CaP (CaP%) in all stones of 1201 patients, and classified them into CaOx (N= 1011) or CaP (N= 190). Sex differences, stone formation rates, urine stone risk factors, extracorporeal shock wave lithotripsy (ESWL) treatments, and relapse during treatment were quantified in relation to stone CaP content. RESULTS CaP% has risen for three decades, especially among women. ESWL rates adjusted for numbers of stones and duration of stone disease were higher in CaP SF (0.6 vs. 1.86 and 0.73 vs. 1.82, CaOx vs. CaP, men and women, respectively, P < 0.001), and especially when stones contained brushite (2.90 vs. 1.02 and 3.11 vs. 1.35, brushite vs. not, males and females, respectively, P < 0.001). Urine pH and CaP supersaturation rose in proportion to CaP% in a dose response manner. Relapse rates of CaP and CaOx SF did not differ, and both did well with medical prevention. CONCLUSION Stone CaP% has risen for three decades. CaP SF, particularly with brushite stones, receive more ESWL treatments than CaOx SF, not explained by stone number or duration of stone disease. Urine supersaturations explain the high CaP%. High CaP% does not hamper medical stone prevention.
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Affiliation(s)
- Joan H Parks
- Nephrology Section, Department of Medicine, University of Chicago, Chicago, Illinois 60637, USA
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29
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Affiliation(s)
- Malvinder S Parmar
- Medical Program (Internal Medicine), Timmins and District Hospital, Timmins, ON, Canada P4N 8R1.
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