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Wieërs MLAJ, Beynon-Cobb B, Visser WJ, Attaye I. Dietary acid load in health and disease. Pflugers Arch 2024; 476:427-443. [PMID: 38282081 PMCID: PMC11006742 DOI: 10.1007/s00424-024-02910-7] [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: 10/27/2023] [Revised: 01/07/2024] [Accepted: 01/09/2024] [Indexed: 01/30/2024]
Abstract
Maintaining an appropriate acid-base equilibrium is crucial for human health. A primary influencer of this equilibrium is diet, as foods are metabolized into non-volatile acids or bases. Dietary acid load (DAL) is a measure of the acid load derived from diet, taking into account both the potential renal acid load (PRAL) from food components like protein, potassium, phosphorus, calcium, and magnesium, and the organic acids from foods, which are metabolized to bicarbonate and thus have an alkalinizing effect. Current Western diets are characterized by a high DAL, due to large amounts of animal protein and processed foods. A chronic low-grade metabolic acidosis can occur following a Western diet and is associated with increased morbidity and mortality. Nutritional advice focusing on DAL, rather than macronutrients, is gaining rapid attention as it provides a more holistic approach to managing health. However, current evidence for the role of DAL is mainly associative, and underlying mechanisms are poorly understood. This review focusses on the role of DAL in multiple conditions such as obesity, cardiovascular health, impaired kidney function, and cancer.
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Affiliation(s)
- Michiel L A J Wieërs
- Department of Internal Medicine, Division of Nephrology and Transplantation, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Beverley Beynon-Cobb
- Department of Nutrition & Dietetics, University Hospitals Coventry & Warwickshire NHS Trust, Coventry, UK
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - Wesley J Visser
- Department of Internal Medicine, Division of Nephrology and Transplantation, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
- Department of Internal Medicine, Division of Dietetics, Erasmus MC, University Medical Center, Rotterdam, The Netherlands
| | - Ilias Attaye
- Department of Internal Medicine, Division of Nephrology and Transplantation, Erasmus MC, University Medical Center, Rotterdam, The Netherlands.
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK.
- Amsterdam Cardiovascular Sciences, Diabetes & Metabolism, Amsterdam, The Netherlands.
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2
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Kuhn C, Mohebbi N, Ritter A. Metabolic acidosis in chronic kidney disease: mere consequence or also culprit? Pflugers Arch 2024; 476:579-592. [PMID: 38279993 PMCID: PMC11006741 DOI: 10.1007/s00424-024-02912-5] [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: 11/15/2023] [Revised: 01/11/2024] [Accepted: 01/12/2024] [Indexed: 01/29/2024]
Abstract
Metabolic acidosis is a frequent complication in non-transplant chronic kidney disease (CKD) and after kidney transplantation. It occurs when net endogenous acid production exceeds net acid excretion. While nephron loss with reduced ammoniagenesis is the main cause of acid retention in non-transplant CKD patients, additional pathophysiological mechanisms are likely inflicted in kidney transplant recipients. Functional tubular damage by calcineurin inhibitors seems to play a key role causing renal tubular acidosis. Notably, experimental and clinical studies over the past decades have provided evidence that metabolic acidosis may not only be a consequence of CKD but also a driver of disease. In metabolic acidosis, activation of hormonal systems and the complement system resulting in fibrosis have been described. Further studies of changes in renal metabolism will likely contribute to a deeper understanding of the pathophysiology of metabolic acidosis in CKD. While alkali supplementation in case of reduced serum bicarbonate < 22 mmol/l has been endorsed by CKD guidelines for many years to slow renal functional decline, among other considerations, beneficial effects and thresholds for treatment have lately been under intense debate. This review article discusses this topic in light of the most recent results of trials assessing the efficacy of dietary and pharmacological interventions in CKD and kidney transplant patients.
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Affiliation(s)
- Christian Kuhn
- Clinic for Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland
| | | | - Alexander Ritter
- Clinic for Nephrology and Transplantation Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.
- Clinic for Nephrology, University Hospital Zurich, Zurich, Switzerland.
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3
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Goraya N, Wesson DE. Pathophysiology of Diet-Induced Acid Stress. Int J Mol Sci 2024; 25:2336. [PMID: 38397012 PMCID: PMC10888592 DOI: 10.3390/ijms25042336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 02/13/2024] [Accepted: 02/14/2024] [Indexed: 02/25/2024] Open
Abstract
Diets can influence the body's acid-base status because specific food components yield acids, bases, or neither when metabolized. Animal-sourced foods yield acids and plant-sourced food, particularly fruits and vegetables, generally yield bases when metabolized. Modern diets proportionately contain more animal-sourced than plant-sourced foods, are, thereby, generally net acid-producing, and so constitute an ongoing acid challenge. Acid accumulation severe enough to reduce serum bicarbonate concentration, i.e., manifesting as chronic metabolic acidosis, the most extreme end of the continuum of "acid stress", harms bones and muscles and appears to enhance the progression of chronic kidney disease (CKD). Progressive acid accumulation that does not achieve the threshold amount necessary to cause chronic metabolic acidosis also appears to have deleterious effects. Specifically, identifiable acid retention without reduced serum bicarbonate concentration, which, in this review, we will call "covert acidosis", appears to cause kidney injury and exacerbate CKD progression. Furthermore, the chronic engagement of mechanisms to mitigate the ongoing acid challenge of modern diets also appears to threaten health, including kidney health. This review describes the full continuum of "acid stress" to which modern diets contribute and the mechanisms by which acid stress challenges health. Ongoing research will develop clinically useful tools to identify stages of acid stress earlier than metabolic acidosis and determine if dietary acid reduction lowers or eliminates the threats to health that these diets appear to cause.
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Affiliation(s)
- Nimrit Goraya
- Department of Internal Medicine, Baylor Scott & White Health, Temple, TX 76508, USA;
- Department of Internal Medicine, Texas A&M Health Science Center College of Medicine, Temple, TX 76508, USA
| | - Donald E. Wesson
- Department of Internal Medicine, Dell Medical School, The University of Texas at Austin, Dallas, TX 78712, USA
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4
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Goraya N, Montgomery AH, Kalantar-Zadeh K, Moore LW, Wesson DE. Diet is Foundational to the Management of Chronic Kidney Disease. J Ren Nutr 2024; 34:1-3. [PMID: 38160704 DOI: 10.1053/j.jrn.2023.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 12/27/2023] [Indexed: 01/03/2024] Open
Affiliation(s)
- Nimrit Goraya
- Baylor College of Medicine, Temple, Texas; Baylor Scott & White Health, Temple, Texas
| | | | | | - Linda W Moore
- Houston Methodist Hospital, Department of Surgery, Houston, Texas
| | - Donald E Wesson
- Dell Medical School - The University of Texas at Austin, Austin, Texas.
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5
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Al-Beltagi M, Saeed NK, Bediwy AS, Elbeltagi R, Hasan S, Hamza MB. Renal calcification in children with renal tubular acidosis: What a paediatrician should know. World J Clin Pediatr 2023; 12:295-309. [PMID: 38178934 PMCID: PMC10762599 DOI: 10.5409/wjcp.v12.i5.295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 09/15/2023] [Accepted: 10/16/2023] [Indexed: 12/08/2023] Open
Abstract
Renal tubular acidosis (RTA) can lead to renal calcification in children, which can cause various complications and impair renal function. This review provides pediatricians with a comprehensive understanding of the relationship between RTA and renal calcification, highlighting essential aspects for clinical management. The article analyzed relevant studies to explore the prevalence, risk factors, underlying mechanisms, and clinical implications of renal calcification in children with RTA. Results show that distal RTA (type 1) is particularly associated with nephrocalcinosis, which presents a higher risk of renal calcification. However, there are limitations to the existing literature, including a small number of studies, heterogeneity in methodologies, and potential publication bias. Longitudinal data and control groups are also lacking, which limits our understanding of long-term outcomes and optimal management strategies for children with RTA and renal calcification. Pediatricians play a crucial role in the early diagnosis and management of RTA to mitigate the risk of renal calcification and associated complications. In addition, alkaline therapy remains a cornerstone in the treatment of RTA, aimed at correcting the acid-base imbalance and reducing the formation of kidney stones. Therefore, early diagnosis and appropriate therapeutic interventions are paramount in preventing and managing renal calcification to preserve renal function and improve long-term outcomes for affected children. Further research with larger sample sizes and rigorous methodologies is needed to optimize the clinical approach to renal calcification in the context of RTA in the pediatric population.
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Affiliation(s)
- Mohammed Al-Beltagi
- Department of Pediatrics, Faculty of Medicine, Tanta University, Tanta 31511, Alghrabia, Egypt
- Department of Pediatrics, University Medical Center, King Abdulla Medical City, Dr. Sulaiman Al Habib Medical Group, Manama, Bahrain, Manama 26671, Manama, Bahrain
| | - Nermin Kamal Saeed
- Medical Microbiology Section, Department of Pathology, Salmaniya Medical Complex, Ministry of Health, Kingdom of Bahrain, Manama 12, Manama, Bahrain
- Medical Microbiology Section, Department of Pathology, Irish Royal College of Surgeon, Bahrain, Busaiteen 15503, Muharraq, Bahrain
| | - Adel Salah Bediwy
- Department of Pulmonology, Faculty of Medicine, Tanta University, Tanta 31527, Alghrabia, Egypt
- Department of Chest Disease, University Medical Center, King Abdulla Medical City, Arabian Gulf University, Dr. Sulaiman Al Habib Medical Group, Manama, Manama 26671, Manama, Bahrain
| | - Reem Elbeltagi
- Department of Medicine, The Royal College of Surgeons in Ireland - Bahrain, Busiateen 15503, Muharraq, Bahrain
| | - Samir Hasan
- Department of Pediatrics, Faculty of Medicine, Tanta University Hospital, Tanta 31511, Algharbia, Egypt
| | - Mohamed Basiony Hamza
- Department of Pediatrics, Faculty of Medicine, Tanta University, Tanta 31511, Algharbia, Egypt
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Ganesan C, Thomas I, Montez‐Rath ME, Chertow GM, Leppert JT, Pao AC. Hypocitraturia and Risk of Bone Disease in Patients With Kidney Stone Disease. JBMR Plus 2023; 7:e10786. [PMID: 37701146 PMCID: PMC10494504 DOI: 10.1002/jbm4.10786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 05/24/2023] [Accepted: 06/01/2023] [Indexed: 09/14/2023] Open
Abstract
Patients with kidney stone disease are at higher risk for bone disease. Hypocitraturia is common in patients with kidney stone disease and a key risk factor for stone recurrence. In this retrospective cohort study, we sought to determine whether hypocitraturia is also a risk factor for incident bone disease in patients with kidney stone disease. We used nationwide data from the Veterans Health Administration and identified 9025 patients with kidney stone disease who had a 24-hour urine citrate measurement between 2007 and 2015. We examined clinical characteristics of patients by level of 24-hour urine citrate excretion (<200, 200-400, and >400 mg/d) and the time to osteoporosis or fracture according to 24-hour urine citrate excretion level. Almost one in five veterans with kidney stone disease and a 24-hour urine citrate measurement had severe hypocitraturia, defined as <200 mg/d. Patients with severe hypocitraturia were at risk for osteoporosis or fracture (hazard ratio [HR] = 1.23; confidence interval [CI] 1.03-1.48), but after adjustment for demographic factors, comorbid conditions, and laboratory abnormalities associated with hypocitraturia, the association was no longer statistically significant (HR = 1.18; CI 0.98-1.43). Our results in a predominantly male cohort suggest a modest association between hypocitraturia and osteoporosis or fracture; there are likely to be other explanations for the potent association between kidney stone disease and diminished bone health. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Calyani Ganesan
- Department of Medicine, Division of NephrologyStanford UniversityPalo AltoCAUSA
| | - I‐Chun Thomas
- Division of Nephrology and Department of UrologyVeterans Affairs Palo Alto Health Care SystemPalo AltoCAUSA
| | - Maria E Montez‐Rath
- Department of Medicine, Division of NephrologyStanford UniversityPalo AltoCAUSA
| | - Glenn M Chertow
- Department of Medicine, Division of NephrologyStanford UniversityPalo AltoCAUSA
| | - John T Leppert
- Department of Medicine, Division of NephrologyStanford UniversityPalo AltoCAUSA
- Division of Nephrology and Department of UrologyVeterans Affairs Palo Alto Health Care SystemPalo AltoCAUSA
- Department of UrologyStanford UniversityPalo AltoCAUSA
| | - Alan C Pao
- Department of Medicine, Division of NephrologyStanford UniversityPalo AltoCAUSA
- Division of Nephrology and Department of UrologyVeterans Affairs Palo Alto Health Care SystemPalo AltoCAUSA
- Department of UrologyStanford UniversityPalo AltoCAUSA
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Kim Y, Lee J, Kang MS, Song J, Kim SG, Cho S, Huh H, Lee S, Park S, Jo HA, Yang SH, Paek JH, Park WY, Han SS, Lee H, Lee JP, Joo KW, Lim CS, Hwang GS, Kim DK. Urinary Metabolite Profile Predicting the Progression of CKD. KIDNEY360 2023; 4:1048-1057. [PMID: 37291728 PMCID: PMC10476680 DOI: 10.34067/kid.0000000000000158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 05/17/2023] [Indexed: 06/10/2023]
Abstract
Key Points As a biomarker, urinary metabolites could bridge the gap between genetic abnormalities and phenotypes of diseases. We found that levels of betaine, choline, fumarate, citrate, and glucose were significantly correlated with kidney function and could predict kidney outcomes, providing prognostic biomarkers in CKD. Background Because CKD is caused by genetic and environmental factors, biomarker development through metabolomic analysis, which reflects gene-derived downstream effects and host adaptation to the environment, is warranted. Methods We measured the metabolites in urine samples collected from 789 patients at the time of kidney biopsy and from urine samples from 147 healthy participants using nuclear magnetic resonance. The composite outcome was defined as a 30% decline in eGFR, doubling of serum creatinine levels, or end-stage kidney disease. Results Among the 28 candidate metabolites, we identified seven metabolites showing (1 ) good discrimination between healthy controls and patients with stage 1 CKD and (2 ) a consistent change in pattern from controls to patients with advanced-stage CKD. Among the seven metabolites, betaine, choline, glucose, fumarate, and citrate showed significant associations with the composite outcome after adjustment for age, sex, eGFR, the urine protein–creatinine ratio, and diabetes. Furthermore, adding choline, glucose, or fumarate to traditional biomarkers, including eGFR and proteinuria, significantly improved the ability of the net reclassification improvement (P < 0.05) and integrated discrimination improvement (P < 0.05) to predict the composite outcome. Conclusion Urinary metabolites, including betaine, choline, fumarate, citrate, and glucose, were found to be significant predictors of the progression of CKD. As a signature of kidney injury–related metabolites, it would be warranted to monitor to predict the renal outcome.
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Affiliation(s)
- Yaerim Kim
- Department of Internal Medicine, Keimyung University School of Medicine, Daegu, Korea
| | - Jueun Lee
- Integrated Metabolomics Research Group, Western Seoul center, Korea Basic Science Institute, Seoul, Republic of Korea
| | - Mi Sun Kang
- Integrated Metabolomics Research Group, Western Seoul center, Korea Basic Science Institute, Seoul, Republic of Korea
| | - Jeongin Song
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
| | - Seong Geun Kim
- Department of Internal Medicine, Inje University Sanggye Paik Hospital, Seoul, Korea
| | - Semin Cho
- Department of Internal Medicine, Chungang University Gwangmyeong hospital, Gyeonggi-do, Korea
| | - Hyuk Huh
- Department of Internal Medicine, Inje University Busan Paik Hospital, Busan, Korea
| | - Soojin Lee
- Department of Internal Medicine, Uijeongbu Eulji University Medical Center, Gyeonggi-do, Korea
| | - Sehoon Park
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
| | - Hyung Ah Jo
- Department of Internal Medicine, Inje University Ilsan Paik Hospital, Ilsan, Korea
| | - Seung Hee Yang
- Kidney Research Institute, Seoul National University, Seoul, Korea
| | - Jin Hyuk Paek
- Department of Internal Medicine, Keimyung University School of Medicine, Daegu, Korea
| | - Woo Yeong Park
- Department of Internal Medicine, Keimyung University School of Medicine, Daegu, Korea
| | - Seung Seok Han
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
| | - Hajeong Lee
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
| | - Jung Pyo Lee
- Department of Internal Medicine, SMG-SNU Boramae Medical Center, Seoul, Korea
- Departement of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Kwon Wook Joo
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
- Departement of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Chun Soo Lim
- Department of Internal Medicine, SMG-SNU Boramae Medical Center, Seoul, Korea
- Departement of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Geum-Sook Hwang
- Integrated Metabolomics Research Group, Western Seoul center, Korea Basic Science Institute, Seoul, Republic of Korea
- College of Pharmacy, Chung-Ang University, Seoul, Republic of Korea
| | - Dong Ki Kim
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
- Departement of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
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Pao AC, Shahzad SR, Song S, Ganesan C, Conti S, Leppert J, Cheung AK, Ix JH, Isakova T, Wolf M, Raj DS, Sprague SM, Fried LF, Gassman J, Fong P, Koike S, Raphael KL. Response to Alkali Administration in Women and Men With and Without CKD. Kidney Med 2023; 5:100670. [PMID: 37492113 PMCID: PMC10363557 DOI: 10.1016/j.xkme.2023.100670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/27/2023] Open
Affiliation(s)
- Alan C. Pao
- Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Palo Alto, California
- Department of Urology, Stanford University School of Medicine, Palo Alto, California
| | - Sheikh R. Shahzad
- Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Palo Alto, California
| | - Shen Song
- Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Palo Alto, California
| | - Calyani Ganesan
- Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Palo Alto, California
| | - Simon Conti
- Department of Urology, Stanford University School of Medicine, Palo Alto, California
| | - John Leppert
- Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Palo Alto, California
- Department of Urology, Stanford University School of Medicine, Palo Alto, California
| | - Alfred K. Cheung
- Division of Nephrology and Hypertension, Department of Medicine, University of Utah School of Medicine, Salt Lake City, Utah
| | - Joachim H. Ix
- Division of Nephrology and Hypertension, Department of Medicine, University of California San Diego School of Medicine, San Diego, California
| | - Tamara Isakova
- Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Myles Wolf
- Division of Nephrology, Department of Medicine, Duke Clinical Research Institute, Duke University, Durham, North Carolina
| | - Dominic S. Raj
- Division of Renal Diseases and Hypertension, Department of Medicine, George Washington University School of Medicine, Washington, DC
| | - Stuart M. Sprague
- Department of Medicine, Northshore University Health System, University of Chicago, Evanston, Illinois
| | - Linda F. Fried
- Department of Medicine, University of Pittsburgh and Renal Section, Veterans Affairs Pittsburgh Health Care System, Pittsburgh, Pennsylvania
| | - Jennifer Gassman
- Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio
| | - Peter Fong
- Division of Nephrology and Hypertension, Department of Medicine, Oregon Health and Science University School of Medicine, Portland, Oregon
| | - Seiji Koike
- Biostatistics and Design Program, Oregon Health and Science University, Portland, Oregon
| | - Kalani L. Raphael
- Division of Nephrology and Hypertension, Department of Medicine, University of Utah School of Medicine, Salt Lake City, Utah
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Wang J, Chen G, Chen H, Chen J, Su Q, Zhuang W. Exploring the characteristics of gut microbiome in patients of Southern Fujian with hypocitraturia urolithiasis and constructing clinical diagnostic models. Int Urol Nephrol 2023:10.1007/s11255-023-03662-6. [PMID: 37294502 DOI: 10.1007/s11255-023-03662-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 06/04/2023] [Indexed: 06/10/2023]
Abstract
PURPOSE Hypocitraturia is an important cause of urolithiasis. Exploring the characteristics of the gut microbiome (GMB) of hypocitriuria urolithiasis (HCU) patients can provide new ideas for the treatment and prevention of urolithiasis. METHODS The 24 h urinary citric acid excretion of 19 urolithiasis patients was measured, and patients were divided into the HCU group and the normal citrate urolithiasis (NCU) group. The 16 s ribosomal RNA (rRNA) was used to detect GMB composition differences and construct operational taxonomic units (OTUs) coexistence networks. The key bacterial community was determined by Lefse analysis, Metastats analysis and RandomForest analysis. Redundancy analysis (RDA) and Pearson correlation analysis visualized the correlation between key OTUs and clinical features and then established the disease diagnosis model of microbial-clinical indicators. Finally, PICRUSt2 was used to explore the metabolic pathway of related GMB in HCU patients. RESULTS The alpha diversity of GMB in HCU group was increased and Beta diversity analysis suggested significant differences between HCU and NCU groups, which was related to renal function damage and urinary tract infection. Ruminococcaceae_ge and Turicibacter are the characteristic bacterial groups of HCU. Correlation analysis showed that the characteristic bacterial groups were significantly associated with various clinical features. Based on this, the diagnostic models of microbiome-clinical indicators in HCU patients were constructed with the areas under the curve (AUC) of 0.923 and 0.897, respectively. Genetic and metabolic processes of HCU are affected by changes in GMB abundance. CONCLUSION GMB disorder may be involved in the occurrence and clinical characteristics of HCU by influencing genetic and metabolic pathways. The new microbiome-clinical indicator diagnostic model is effective.
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Affiliation(s)
- Jialiang Wang
- Department of Urology, The Second Affiliated Hospital of Fujian Medical University, Licheng District Zhongshan North Road, Quanzhou, 362000, Fujian, China
| | - Guofeng Chen
- Department of Urology, The Second Affiliated Hospital of Fujian Medical University, Licheng District Zhongshan North Road, Quanzhou, 362000, Fujian, China
| | - Heyi Chen
- Department of Urology, The Second Affiliated Hospital of Fujian Medical University, Licheng District Zhongshan North Road, Quanzhou, 362000, Fujian, China
| | - Jiabi Chen
- Department of Urology, The Second Affiliated Hospital of Fujian Medical University, Licheng District Zhongshan North Road, Quanzhou, 362000, Fujian, China
| | - Qingfu Su
- Department of Urology, The Second Affiliated Hospital of Fujian Medical University, Licheng District Zhongshan North Road, Quanzhou, 362000, Fujian, China.
| | - Wei Zhuang
- Department of Urology, The Second Affiliated Hospital of Fujian Medical University, Licheng District Zhongshan North Road, Quanzhou, 362000, Fujian, China.
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Stepanova N. Oxalate Homeostasis in Non-Stone-Forming Chronic Kidney Disease: A Review of Key Findings and Perspectives. Biomedicines 2023; 11:1654. [PMID: 37371749 DOI: 10.3390/biomedicines11061654] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 06/03/2023] [Accepted: 06/05/2023] [Indexed: 06/29/2023] Open
Abstract
Chronic kidney disease (CKD) is a significant global public health concern associated with high morbidity and mortality rates. The maintenance of oxalate homeostasis plays a critical role in preserving kidney health, particularly in the context of CKD. Although the relationship between oxalate and kidney stone formation has been extensively investigated, our understanding of oxalate homeostasis in non-stone-forming CKD remains limited. This review aims to present an updated analysis of the existing literature, focusing on the intricate mechanisms involved in oxalate homeostasis in patients with CKD. Furthermore, it explores the key factors that influence oxalate accumulation and discusses the potential role of oxalate in CKD progression and prognosis. The review also emphasizes the significance of the gut-kidney axis in CKD oxalate homeostasis and provides an overview of current therapeutic strategies, as well as potential future approaches. By consolidating important findings and perspectives, this review offers a comprehensive understanding of the present knowledge in this field and identifies promising avenues for further research.
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Affiliation(s)
- Natalia Stepanova
- State Institution «Institute of Nephrology of the National Academy of Medical Sciences of Ukraine», 04050 Kyiv, Ukraine
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11
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Koh ES. Hidden Acid Retention with Normal Serum Bicarbonate Level in Chronic Kidney Disease. Electrolyte Blood Press 2023; 21:34-43. [PMID: 37434806 PMCID: PMC10329907 DOI: 10.5049/ebp.2023.21.1.34] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 04/06/2023] [Accepted: 04/16/2023] [Indexed: 07/13/2023] Open
Abstract
Management of metabolic acidosis is crucial for preserving bone, muscle, and renal health, as evidenced by the results of several interventional studies conducted on patients with chronic kidney disease (CKD). Considering the continuity of CKD progression over time, it is reasonable to deduce that a subclinical form of metabolic acidosis may exist prior to the manifestation of overt metabolic acidosis. Covert H+ retention with normal serum bicarbonate level in patients with CKD may result in maladaptive responses that contribute to kidney function deterioration, even in the early stages of the disease. The loss of adaptive compensatory mechanisms of urinary acid excretion may be a key factor in this process. Early modulation of these responses could be an important therapeutic strategy in preventing CKD progression. However, to date, the optimal approach for alkali therapy in subclinical metabolic acidosis in CKD remains uncertain. There is a lack of established guidelines on when to initiate alkali therapy, potential side effects of alkali agents, and the optimal blood bicarbonate levels based on evidence-based practices. Therefore, further research is necessary to address these concerns and establish more robust guidelines for the use of alkali therapy in patients with CKD. Herein, we provide an overview of recent developments on this subject and examine the potential therapeutic approaches that interventional treatments may present for patients with hidden H+ retention, exhibiting normal serum bicarbonate levels - commonly described as subclinical or eubicarbonatemic metabolic acidosis in patients with CKD.
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Affiliation(s)
- Eun Sil Koh
- Division of Nephrology, Department of Internal Medicine, Yeouido St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
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12
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Beynon-Cobb B, Louca P, Hoorn EJ, Menni C, Padmanabhan S. Effect of Sodium Bicarbonate on Systolic Blood Pressure in CKD: A Systematic Review and Meta-Analysis. Clin J Am Soc Nephrol 2023; 18:435-445. [PMID: 36758154 PMCID: PMC10103210 DOI: 10.2215/cjn.0000000000000119] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 01/24/2023] [Indexed: 02/11/2023]
Abstract
BACKGROUND Individuals with CKD are at a higher risk of cardiovascular morbidity and mortality. Acidosis is positively correlated with CKD progression and elevated systolic BP. Sodium bicarbonate is an efficacious treatment of acidosis, although this may also increase systolic BP. In this systematic review and meta-analysis, we summarize the evidence evaluating systolic BP and antihypertensive medication change (which may indicate systolic BP change) in response to sodium bicarbonate therapy in individuals with CKD. METHODS Medical Literature Analysis and Retrieval System Online, Excerpta Medica database, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine Database, Cochrane Central Register of Controlled Trials, and World Health Organization (WHO) trials registry databases were searched for randomized control trials where sodium bicarbonate was compared with placebo/usual care in CKD stage G1-5 non-dialysis-dependent populations. Random effects meta-analyses were used to evaluate changes in systolic BP and BP-modifying drugs after sodium bicarbonate intervention. RESULTS Fourteen randomized control trials (2110 individuals, median follow-up 27 [interquartile range 97] weeks, mean age 60 [SD 10] years, mean systolic BP 136 [SD 17] mm Hg, mean eGFR 38 [SD 10] ml/min, mean serum bicarbonate 22 [SD 4] mmol/L) were eligible for inclusion. Meta-analysis suggested that sodium bicarbonate did not influence systolic BP in individuals with CKD stage G1-5. Results were consistent when stratifying by dose of sodium bicarbonate or duration of intervention. Similarly, there was no significant increase in the use of antihypertensive medication or diuretics in individuals taking sodium bicarbonate, whereas there was a greater decrease in antihypertensive medication use in individuals taking sodium bicarbonate compared with controls. CONCLUSIONS Our results suggest, with moderate certainty, that sodium bicarbonate supplementation does not adversely affect systolic BP in CKD or negatively influence antihypertensive medication requirements.
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Affiliation(s)
- Beverley Beynon-Cobb
- Department of Nutrition & Dietetics, University Hospitals Coventry & Warwickshire NHS Trust, Coventry, United Kingdom
- Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom
| | - Panayiotis Louca
- Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom
| | - Ewout J. Hoorn
- Department of Internal Medicine, Divisions of Nephrology and Transplantation, Erasmus Medical Center, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Cristina Menni
- Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom
| | - Sandosh Padmanabhan
- BHF Glasgow Cardiovascular Research Centre, School of Cardiovascular & Metabolic Health, University of Glasgow, Glasgow, United Kingdom
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13
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Malieckal DA, Ganesan C, Mendez DA, Pao AC. Breaking the Cycle of Recurrent Calcium Stone Disease. ADVANCES IN KIDNEY DISEASE AND HEALTH 2023; 30:164-176. [PMID: 36868731 PMCID: PMC9993408 DOI: 10.1053/j.akdh.2022.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 12/14/2022] [Indexed: 03/05/2023]
Abstract
Calcium stones are common and recurrent in nature, yet few therapeutic tools are available for secondary prevention. Personalized approaches for stone prevention have been informed by 24-hour urine testing to guide dietary and medical interventions. However, current evidence is conflicting about whether an approach guided by 24-hour urine testing is more effective than a generic one. The available medications for stone prevention, namely thiazide diuretics, alkali, and allopurinol, are not always prescribed consistently, dosed correctly, or tolerated well by patients. New treatments on the horizon hold the promise of preventing calcium oxalate stones by degrading oxalate in the gut, reprogramming the gut microbiome to reduce oxalate absorption, or knocking down expression of enzymes involved in hepatic oxalate production. New treatments are also needed to target Randall's plaque, the root cause of calcium stone formation.
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Affiliation(s)
- Deepa A. Malieckal
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Great Neck, NY
| | - Calyani Ganesan
- Stanford University School of Medicine, Department of Medicine, Palo Alto, CA
| | | | - Alan C. Pao
- Stanford University School of Medicine, Department of Medicine, Palo Alto, CA
- Veterans Affairs Palo Alto Health Care System, Palo Alto, CA
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14
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Sodium zirconium cyclosilicate and metabolic acidosis: Potential mechanisms and clinical consequences. Biomed Pharmacother 2023; 158:114197. [PMID: 36916426 DOI: 10.1016/j.biopha.2022.114197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 12/23/2022] [Accepted: 12/29/2022] [Indexed: 01/05/2023] Open
Abstract
Metabolic acidosis is frequent in chronic kidney disease (CKD) and is associated with accelerated progression of CKD, hypercatabolism, bone disease, hyperkalemia, and mortality. Clinical guidelines recommend a target serum bicarbonate ≥ 22 mmol/L, but metabolic acidosis frequently remains undiagnosed and untreated. Sodium zirconium cyclosilicate (SZC) binds potassium in the gut and is approved to treat hyperkalemia. In clinical trials with a primary endpoint of serum potassium, SZC increased serum bicarbonate, thus treating CKD-associated metabolic acidosis. The increase in serum bicarbonate was larger in patients with more severe pre-existent metabolic acidosis, was associated to decreased serum urea and was maintained for over a year of SZC therapy. SZC also decreased serum urea and increased serum bicarbonate after switching from a potassium-binding resin in normokalemic individuals. Mechanistically, these findings are consistent with SZC binding the ammonium ion (NH4+) generated from urea by gut microbial urease, preventing its absorption and, thus, preventing the liver regeneration of urea and promoting the fecal excretion of H+. This mechanism of action may potentially result in benefits dependent on corrected metabolic acidosis (e.g., improved well-being, decreased catabolism, improved CKD mineral bone disorder, better control of serum phosphate, slower progression of CKD) and dependent on lower urea levels, such as decreased protein carbamylation. A roadmap is provided to guide research into the mechanisms and clinical consequences of the impact of SZC on serum bicarbonate and urate.
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15
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Naude, MTech (Hom) DF. Chronic Sub-Clinical Systemic Metabolic Acidosis - A Review with Implications for Clinical Practice. J Evid Based Integr Med 2022; 27:2515690X221142352. [PMID: 36448194 PMCID: PMC9716591 DOI: 10.1177/2515690x221142352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
When arterial serum pH remains near the lower pH limit of 7.35 for protracted periods of time, a low-grade, sub-clinical form of acidosis results, referred to in this review as chronic, sub-clinical, systemic metabolic acidosis (CSSMA). This narrative review explores the scientific basis for CSSMA, its consequences for health, and potential therapeutic interventions. The major etiology of CSSMA is the shift away from the ancestral, alkaline diet which was rich in fruit and vegetables, toward the contemporary, acidogenic 'Westernized' diet characterized by higher animal protein consumption and lack of base forming minerals. Urine pH is reduced with high dietary acid load and may be a convenient marker of CSSMA. Evidence suggests further that CSSMA negatively influences cortisol levels potentially contributing significantly to the pathophysiology thereof. Both CSSMA and high dietary acid load are associated with the risk and prognosis of various chronic diseases. Clinical trials show that CSSMA can be addressed successfully through alkalizing the diet by increasing fruit and vegetable intake and/or supplementing with alkaline minerals. This review confirms the existence of a significant body of evidence regarding this low-grade form of acidosis as well as evidence to support its diverse negative implications for health, and concludes that CSSMA is a condition warranting further research.
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Affiliation(s)
- David Francis Naude, MTech (Hom)
- Irma Schutte Foundation, Drummond, South Africa,David Francis Naude, Irma Schutte Foundation, 42 Protea Hill Rd, Drummond, KwaZulu Natal, 3626, South Africa. Postal address: P.O Box 8, Hillcrest, KwaZulu Natal, 3650, South Africa.
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16
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Wesson DE. The Importance of Recognizing and Addressing the Spectrum of Acid Stress. Adv Chronic Kidney Dis 2022; 29:364-372. [PMID: 36175074 DOI: 10.1053/j.ackd.2022.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 06/01/2022] [Accepted: 06/09/2022] [Indexed: 01/25/2023]
Abstract
Acid accumulation sufficient to reduce plasma bicarbonate concentration, thereby recognized as chronic metabolic acidosis, harms bones and muscles and appears to enhance progression of CKD. Evolving evidence supports that progressive acid accumulation that is not enough to cause chronic metabolic acidosis nevertheless has deleterious effects. Measurable acid retention without reduced plasma bicarbonate concentration, called eubicarbonatemic acidosis, also appears to cause kidney injury and exacerbate CKD progression. Furthermore, chronic engagement of mechanisms to mitigate the ongoing acid challenge of net acid-producing diets of developed societies also appears to be deleterious, including for kidney health. This review challenges clinicians to consider the growing evidence for a spectrum of acid-accumulation disorders that include lesser degrees of acid accumulation than metabolic acidosis yet are harmful. Further research will develop clinically useful tools to identify individuals suffering from these earlier stages of acid stress and determine if the straightforward and comparatively inexpensive intervention of dietary acid reduction relieves or eliminates the harm they appear to cause.
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Affiliation(s)
- Donald E Wesson
- The University of Texas at Austin Dell Medical School, Austin, TX; Donald E Wesson Consulting LLC, Dallas, TX.
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17
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Moe OW, Maalouf NM, Sakhaee K, Lederer E. Preclinical and Clinical Evidence of Effect of Acid on Bone Health. Adv Chronic Kidney Dis 2022; 29:381-394. [PMID: 36175076 DOI: 10.1053/j.ackd.2022.07.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Acid can have ill effect on bone health in the absence of frank clinical acidosis but affecting the bone mioneral matrix and bone cells via complex pathways botyh ascute;y and chronically. While the reaction of bone to an acid load is conserved in evolution and is adaptive, the capacity can be overwhelmed resulting in dire consequences. The preclinical an clincl evidence of the acdi effect on bone is very convincing and the clinical evidence in both association and interventiopn studies are also quite credible, The adverse effects of acid on bone is underappreoicated, under-investigated, and the potential benefits of alkali therapy is not generrally known.
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Affiliation(s)
- Orson W Moe
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX; Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX.
| | - Naim M Maalouf
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
| | - Khashayar Sakhaee
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX
| | - Eleanor Lederer
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX; Medical Service, VA North Texas Health Care System, Dallas, TX
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18
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Ravikumar NPG, Pao AC, Raphael KL. Acid-Mediated Kidney Injury Across the Spectrum of Metabolic Acidosis. Adv Chronic Kidney Dis 2022; 29:406-415. [PMID: 36175078 DOI: 10.1053/j.ackd.2022.04.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 04/15/2022] [Accepted: 04/25/2022] [Indexed: 01/25/2023]
Abstract
Metabolic acidosis affects about 15% of patients with chronic kidney disease. As kidney function declines, the kidneys progressively fail to eliminate acid, primarily reflected by a decrease in ammonium and titratable acid excretion. Several studies have shown that the net acid load remains unchanged in patients with reduced kidney function; the ensuing acid accumulation can precede overt metabolic acidosis, and thus, indicators of urinary acid or potential base excretion, such as ammonium and citrate, may serve as early signals of impending metabolic acidosis. Acid retention, with or without overt metabolic acidosis, initiates compensatory responses that can promote tubulointerstitial fibrosis via intrarenal complement activation and upregulation of endothelin-1, angiotensin II, and aldosterone pathways. The net effect is a cycle between acid accumulation and kidney injury. Results from small- to medium-sized interventional trials suggest that interrupting this cycle through base administration can prevent further kidney injury. While these findings inform current clinical practice guidelines, large-scale clinical trials are still necessary to prove that base therapy can limit chronic kidney disease progression or associated adverse events.
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Affiliation(s)
- Naveen P G Ravikumar
- Division of Nephrology & Hypertension, Department of Medicine, Oregon Health & Science University, Portland, OR; Veterans Affairs Portland Health Care System, Portland, OR
| | - Alan C Pao
- Division of Nephrology, Department of Medicine, Stanford University School of Medicine, Stanford, CA; Veterans Affairs Palo Alto Health Care System, Palo Alto, CA
| | - Kalani L Raphael
- Division of Nephrology & Hypertension, Department of Medicine, Oregon Health & Science University, Portland, OR; Veterans Affairs Portland Health Care System, Portland, OR.
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19
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Abstract
Eating a net acid-producing diet can produce an "acid stress" of severity proportional to the diet net acid load, as indexed by the steady-state renal net acid excretion rate. Depending on how much acid or base is ingested or produced from endogenous metabolic processes and how well our homeostatic mechanisms can buffer or eliminate the additional acids or bases, we can alter our systemic acid-base balance. With increasing age, the kidney's ability to excrete daily net acid loads declines (a condition similar to that of mild CKD), invoking increased utilization of potential base stores (eg, bone, skeletal muscle) on a daily basis to mitigate the acid accumulation, thereby contributing to development of osteoporosis, loss of muscle mass, and age-related renal insufficiency. Patients suffering from more advanced CKD often present with more severe acid stress or metabolic acidosis, as the kidney can no longer excrete the entire acid load. Alkaline diets based on fruits and vegetables may have a positive effect on long-term preservation of renal function while maintaining nutritional status. This chapter discusses the biochemistry of dietary precursors that affect acid or base production.
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Affiliation(s)
- Lynda Frassetto
- Department of Medicine, University of California San Francisco, San Francisco, CA.
| | - Thomas Remer
- Department of Nutrition and Lifestyle Sciences, University of Bonn, Bonn, Germany
| | - Tanushree Banerjee
- Department of Medicine, University of California San Francisco, San Francisco, CA
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20
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Mohammadi-Shemirani P, Chong M, Perrot N, Pigeyre M, Steinberg GR, Paré G, Krepinsky JC, Lanktree MB. ACLY and CKD: A Mendelian Randomization Analysis. Kidney Int Rep 2022; 7:1673-1681. [PMID: 35812273 PMCID: PMC9263230 DOI: 10.1016/j.ekir.2022.04.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 04/06/2022] [Accepted: 04/11/2022] [Indexed: 11/15/2022] Open
Abstract
Introduction Adenosine triphosphate-citrate lyase (ACLY) inhibition is a therapeutic strategy under investigation for atherosclerotic cardiovascular disease, nonalcoholic steatohepatitis, and metabolic syndrome. Mouse models suggest that ACLY inhibition could reduce inflammation and kidney fibrosis. Genetic analysis of ACLY in chronic kidney disease (CKD) has not been performed. Methods We constructed a genetic instrument by selecting variants associated with ACLY expression in the expression quantitative trait loci genetics consortium (eQTLGen) from blood samples from 31,684 participants. In a 2-sample Mendelian randomization analysis, we evaluated the effect of genetically predicted ACLY expression on the risk of CKD, estimated glomerular filtration rate (eGFR), and albumin-to-creatinine ratio (ACR) using the CKD Genetics (CKDGen) consortium, UK Biobank, and the Finnish Genetics (FinnGen) consortium totaling 66,396 CKD cases and 958,517 controls. Results ACLY is constitutively expressed in all cell types including in whole blood. The genetic instrument included 13 variants and explained 1.5% of the variation in whole blood ACLY gene expression. A 34% reduction in ACLY expression score was associated with a 0.04 mmol/l reduced low-density lipoprotein (LDL) cholesterol (P = 3.4 × 10-4) and a 9% reduced risk of CKD (stages 3, 4, 5, dialysis, or eGFR < 60 ml/min per 1.73 m2) (odds ratio [OR] = 0.91, 95% CI: 0.85-0.98, P = 0.008), but no association was observed with either eGFR or ACR. Conclusion Mendelian randomization analyses revealed that genetically reduced ACLY expression was associated with reduced risk of CKD but had no effect on either eGFR or ACR. Further evaluation of ACLY in kidney disease is warranted.
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Affiliation(s)
- Pedrum Mohammadi-Shemirani
- Department of Biomarkers and Genetics, Population Health Research Institute, Hamilton, Ontario, Canada.,Experimental Program, Thrombosis and Atherosclerosis Research Institute, Hamilton, Ontario, Canada.,Department of Medical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Michael Chong
- Department of Biomarkers and Genetics, Population Health Research Institute, Hamilton, Ontario, Canada.,Experimental Program, Thrombosis and Atherosclerosis Research Institute, Hamilton, Ontario, Canada.,Department of Medical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Nicolas Perrot
- Department of Biomarkers and Genetics, Population Health Research Institute, Hamilton, Ontario, Canada
| | - Marie Pigeyre
- Department of Biomarkers and Genetics, Population Health Research Institute, Hamilton, Ontario, Canada.,Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Gregory R Steinberg
- Division of Endocrinology and Metabolism, Department of Medicine, McMaster University, Hamilton, Ontario, Canada.,Centre for Metabolism, Obesity, and Diabetes Research, McMaster University, Hamilton, Ontario, Canada.,Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Guillaume Paré
- Department of Biomarkers and Genetics, Population Health Research Institute, Hamilton, Ontario, Canada.,Experimental Program, Thrombosis and Atherosclerosis Research Institute, Hamilton, Ontario, Canada.,Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada.,Department of Health Research Methods, Evidence & Impact, McMaster University, Hamilton, Ontario, Canada
| | - Joan C Krepinsky
- Centre for Metabolism, Obesity, and Diabetes Research, McMaster University, Hamilton, Ontario, Canada.,Division of Nephrology, Department of Medicine, McMaster University, Hamilton, Ontario, Canada.,Division of Nephrology, St. Joseph's Healthcare Hamilton, Hamilton, Ontario, Canada
| | - Matthew B Lanktree
- Department of Biomarkers and Genetics, Population Health Research Institute, Hamilton, Ontario, Canada.,Department of Health Research Methods, Evidence & Impact, McMaster University, Hamilton, Ontario, Canada.,Division of Nephrology, Department of Medicine, McMaster University, Hamilton, Ontario, Canada.,Division of Nephrology, St. Joseph's Healthcare Hamilton, Hamilton, Ontario, Canada
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21
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Nagami GT, Kraut JA. Regulation of Acid-Base Balance in Patients With Chronic Kidney Disease. Adv Chronic Kidney Dis 2022; 29:337-342. [PMID: 36175071 DOI: 10.1053/j.ackd.2022.05.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 05/16/2022] [Accepted: 05/31/2022] [Indexed: 01/25/2023]
Abstract
Normallly the kidneys handle the daily acid load arising from net endogenous acid production from the metabolism of ingested animal protein (acid) and vegetables (base). With chronic kidney disease, reduced acid excretion by the kidneys is primarily due to reduced ammonium excretion such that when acid excertion falls below acid porduction, acid accumulation occurs. With even mild reductions in glomerular filtration rate (60 to 90 ml/min), net acid excretion may fall below net acid production resulting in acid retention which may be initially sequestered in interstitial compartments in the kidneys, bones, and muscles resulting in no fall in measured systemic bicarbonate levels (eubicarbonatemic metabolic acidosis). With greater reductions in kidney function, the greater quantities of acid retained spillover systemically resulting in low pH (overt metabolic acidosis). The evaluation of acid-base balance in patients with CKD is complicated by the heterogeneity of clinical acid-base disorders and by the eubicarbonatemic nature of the early phase of acid retention. If supported by more extensive studies, blood gas analyses to confirm the acid-base disorder and newer ways for assessing the presence of acidosis such as urinary citrate measurements may become routine tools to evaluate and treat acid-base disorders in individuals with CKD.
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Affiliation(s)
- Glenn T Nagami
- Division of Nephrology, Department of Medicine, VA Greater Los Angeles Healthcare System, Los Angeles, CA; David Geffen School of Medicine, UCLA, Los Angeles, CA.
| | - Jeffrey A Kraut
- Division of Nephrology, VHAGLA Healthcare System, Los Angeles, CA; UCLA Membrane Biology Laboratory, David Geffen UCLA School of Medicine, Los Angeles, CA
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22
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Hou B, Lin C, Hao Z. Chronic hepatitis B virus infection increases the risk of upper urinary calculi. BMC Urol 2022; 22:82. [PMID: 35668522 PMCID: PMC9169271 DOI: 10.1186/s12894-022-01038-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 05/27/2022] [Indexed: 11/23/2022] Open
Abstract
Background Although hepatitis B virus (HBV) is a recognized risk factor for renal diseases, little is known about HBV infection in individuals with upper urinary calculi (UUC). We investigated the relationship between chronic HBV infection and UUC. Methods We retrospectively analysed data from 1399 patients who were discharged from the Department of Urology (2017–2018). The diagnosis of UUC was determined using urinary tract ultrasonography or computed tomography, and HBV infection was evaluated by a positive hepatitis B surface antigen (HBsAg) test. Data on patients with and without UUC and HBsAg-positive and HBsAg-negative patients were compared by univariate and multivariate analyses. Results Data on chronic HBV infection and UUC were available for 1062 patients, including 514 who presented with UUC and 548 who did not. Overall, 5.8% of total patients, 8.0% of UUC patients and 3.8% of non-UUC patients had chronic HBV infection. UUC patients (41/514) had a significantly higher prevalence of HBsAg positivity (OR 2.175; 95% CI 1.267–3.734; P = 0.004) than non-UUC patients (21/548). After stratifying by sex, the relative odds of HBsAg positivity were statistically significant in men (OR 2.156; 95% CI 1.162–4.003; P = 0.015) but not in women (OR 2.947; 95% CI 0.816–10.643; P = 0.099). The incidence of urinary pH > 6 and staghorn stones was significantly higher in HBsAg-positive UUC patients than in HBsAg-negative UUC patients. Conclusion This is the first study to demonstrate that chronic HBV infection is strongly associated with UUC, at least in men. The urinary pH > 6 and staghorn stones were more common in UUC patients with chronic HBV infection. Supplementary Information The online version contains supplementary material available at 10.1186/s12894-022-01038-z.
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Affiliation(s)
- Bingbing Hou
- Department of Urology, The First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230032, China.,Institute of Urology, Anhui Medical University, Hefei, China.,Anhui Province Key Laboratory of Genitourinary Diseases, Anhui Medical University, Hefei, China
| | - Changming Lin
- Department of Urology, The Fourth Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Zongyao Hao
- Department of Urology, The First Affiliated Hospital of Anhui Medical University, No. 218 Jixi Road, Hefei, 230032, China. .,Institute of Urology, Anhui Medical University, Hefei, China. .,Anhui Province Key Laboratory of Genitourinary Diseases, Anhui Medical University, Hefei, China.
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23
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Imenez Silva PH, Mohebbi N. Kidney metabolism and acid-base control: back to the basics. Pflugers Arch 2022; 474:919-934. [PMID: 35513635 PMCID: PMC9338915 DOI: 10.1007/s00424-022-02696-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/27/2022] [Accepted: 04/28/2022] [Indexed: 01/18/2023]
Abstract
Kidneys are central in the regulation of multiple physiological functions, such as removal of metabolic wastes and toxins, maintenance of electrolyte and fluid balance, and control of pH homeostasis. In addition, kidneys participate in systemic gluconeogenesis and in the production or activation of hormones. Acid-base conditions influence all these functions concomitantly. Healthy kidneys properly coordinate a series of physiological responses in the face of acute and chronic acid-base disorders. However, injured kidneys have a reduced capacity to adapt to such challenges. Chronic kidney disease patients are an example of individuals typically exposed to chronic and progressive metabolic acidosis. Their organisms undergo a series of alterations that brake large detrimental changes in the homeostasis of several parameters, but these alterations may also operate as further drivers of kidney damage. Acid-base disorders lead not only to changes in mechanisms involved in acid-base balance maintenance, but they also affect multiple other mechanisms tightly wired to it. In this review article, we explore the basic renal activities involved in the maintenance of acid-base balance and show how they are interconnected to cell energy metabolism and other important intracellular activities. These intertwined relationships have been investigated for more than a century, but a modern conceptual organization of these events is lacking. We propose that pH homeostasis indissociably interacts with central pathways that drive progression of chronic kidney disease, such as inflammation and metabolism, independent of etiology.
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Affiliation(s)
- Pedro Henrique Imenez Silva
- Institute of Physiology, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland.
- National Center of Competence in Research NCCR Kidney.CH, Zurich, Switzerland.
| | - Nilufar Mohebbi
- National Center of Competence in Research NCCR Kidney.CH, Zurich, Switzerland
- Praxis Und Dialysezentrum Zurich, Zurich, Switzerland
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24
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Alkali therapy protects renal function, suppresses inflammation, and improves cellular metabolism in kidney disease. Clin Sci (Lond) 2022; 136:557-577. [PMID: 35389462 DOI: 10.1042/cs20220095] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 03/24/2022] [Accepted: 04/07/2022] [Indexed: 11/17/2022]
Abstract
Chronic kidney disease (CKD) affects about 10-13 % of the population worldwide and halting its progression is a major clinical challenge. Metabolic acidosis is both a consequence and a possible driver of CKD progression. Alkali therapy counteracts these effects in CKD patients, but underlying mechanisms remain incompletely understood. Here we show that bicarbonate supplementation protected renal function in a murine CKD model induced by an oxalate-rich diet. Alkali therapy had no effect on the aldosterone-endothelin axis but promoted levels of the anti-aging protein klotho; moreover, it suppressed adhesion molecules required for immune cell invasion along with reducing T helper cell and inflammatory monocyte invasion. Comparing transcriptomes from the murine crystallopathy model and from human biopsies of kidney transplant recipients suffering from acidosis with or without alkali therapy unveils parallel transcriptome responses mainly associated with lipid metabolism and oxidoreductase activity. Our data reveal novel pathways associated with acidosis in kidney disease and sensitive to alkali therapy and identifies potential targets through which alkali therapy may act on CKD and that may be amenable for more targeted therapies.
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25
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Mathur V, Reaven NL, Funk SE, Whitlock R, Ferguson TW, Collister D, Tangri N. Association of metabolic acidosis with fractures, falls, protein-calorie malnutrition, and failure to thrive in patients with chronic kidney disease. Clin Kidney J 2022; 15:1379-1386. [PMID: 35756750 PMCID: PMC9217643 DOI: 10.1093/ckj/sfac065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
The risk of adverse geriatric outcomes such as falls and fractures is high among patients with chronic kidney disease (CKD). Metabolic acidosis is associated with protein catabolism and bone loss in experimental animal and human studies. We sought to quantify the independent association of metabolic acidosis with adverse muscle, bone, and functional outcomes in a large U.S. community-based cohort.
Methods
The Optum's de-identified Integrated Claims-Clinical dataset of US patients (2007-2017) was used to generate a cohort of patients with non-dialysis-dependent CKD who had eGFR >10 to <60 mL/min/1.73 m2 and 2 serum bicarbonate values 12 to <22 mmol/L or 22-29 mmol/L. The primary outcomes were failure to thrive, protein-calorie malnutrition, and fall or fracture. Cox proportional hazards models were used for the primary outcomes for up to 10 years, while logistic regression models were used at 2 years.
Results
51,558 patients qualified for the study, with a median (IQR) follow-up time of 4.2 (2.5-5.8) years. Over a ≤ 10-year period, for each 1-mmol/L increase in serum bicarbonate, the hazard ratios (adjusted for age, sex, race, eGFR, serum albumin, hemoglobin, diabetes and cardiovascular comorbidities) for failure to thrive, protein-calorie malnutrition, and fall or fracture were 0.91 (95% confidence interval [CI], 0.90-0.92), 0.91 (95% CI, 0.90-0.92), and 0.95 (95% CI, 0.95-0.96), all P < 0.001, respectively.
Conclusions
The presence and severity of metabolic acidosis was a significant, independent risk factor for failure to thrive, protein-calorie malnutrition, and fall or fracture in this large community cohort of patients with stage 3-5 CKD.
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Affiliation(s)
| | | | - Susan E Funk
- Strategic Health Resources, La Canada, California, USA
| | - Reid Whitlock
- Department of Internal Medicine, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba; Winnipeg, Manitoba, Canada
| | - Thomas W Ferguson
- Department of Internal Medicine, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba; Winnipeg, Manitoba, Canada
| | - David Collister
- Department of Internal Medicine, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba; Winnipeg, Manitoba, Canada
| | - Navdeep Tangri
- Department of Internal Medicine, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba; Winnipeg, Manitoba, Canada
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26
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Fukasawa H, Kaneko M, Uchiyama Y, Yasuda H, Furuya R. Lower bicarbonate level is associated with CKD progression and all-cause mortality: a propensity score matching analysis. BMC Nephrol 2022; 23:86. [PMID: 35246054 PMCID: PMC8895620 DOI: 10.1186/s12882-022-02712-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Accepted: 02/21/2022] [Indexed: 11/23/2022] Open
Abstract
Background Although metabolic acidosis is known as a potential complication of chronic kidney disease (CKD), there is limited information concerning the association between metabolic acidosis and clinical outcomes. Methods Five hundred fifty-two patients referred to renal division of Iwata City Hospital from 2015 to 2017 were included as a retrospective CKD cohort, and finally 178 patients with CKD stage III or IV and 20 to 80 years of age were analyzed. We examined the association between serum bicarbonate (HCO3−) levels and clinical outcomes using Kaplan-Meier methods after the matching of baseline characteristics by propensity scores. Results Of 178 patients with CKD, patients with lower HCO3− levels (N = 94), as compared with patients with higher HCO3− levels (N = 84), were more likely to be male (P < 0.05), had more severe CKD stages (P < 0.05), more frequent use of renin-angiotensin system inhibitor (P < 0.05) or uric acid lowering agent (P < 0.001), heavier body weight (P < 0.001) and lower estimated glomerular filtration rate (P < 0.05). In Kaplan-Meier analysis after propensity score matching, the incidence of composite outcome as the doubling of serum creatinine level from baseline, end-stage kidney disease requiring the initiation of dialysis, or death from any causes was significantly fewer in the higher HCO3− group than the lower HCO3− group (N = 57 each group, P = 0.016). Conclusions Lower HCO3− level is significantly associated with the doubling of serum creatinine level, end-stage kidney disease or all-cause mortality in patients with CKD. Trial registration This study was registered with the Clinical Trial Registry of the University Hospital Medical Information Network (http://www.umin.ac.jp/, study number: UMIN000044861).
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Affiliation(s)
- Hirotaka Fukasawa
- Renal Division, Department of Internal Medicine, Iwata City Hospital, 512-3 Ohkubo, Iwata, Shizuoka, 438-8550, Japan.
| | - Mai Kaneko
- Renal Division, Department of Internal Medicine, Iwata City Hospital, 512-3 Ohkubo, Iwata, Shizuoka, 438-8550, Japan
| | - Yuri Uchiyama
- Renal Division, Department of Internal Medicine, Iwata City Hospital, 512-3 Ohkubo, Iwata, Shizuoka, 438-8550, Japan
| | - Hideo Yasuda
- First Department of Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Ryuichi Furuya
- Renal Division, Department of Internal Medicine, Iwata City Hospital, 512-3 Ohkubo, Iwata, Shizuoka, 438-8550, Japan
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27
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Abstract
An exploration of the normal limits of physiologic responses and how these responses are lost when the kidney is injured rarely occurs in clinical practice. However, the differences between "resting" and "stressed" responses identify an adaptive reactiveness that is diminished before baseline function is impaired. This functional reserve is important in the evaluation of prognosis and progression of kidney disease. Here, we discuss stress tests that examine protein-induced hyperfiltration, proximal tubular secretion, urea-selective concentration defects, and acid retention. We discuss diseases in which these tests have been used to diagnose subclinical injury. The study and follow-up of abnormal functional reserve may add considerable understanding to the natural history of CKD.
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Affiliation(s)
- Armando Armenta
- Department of Nephrology, National Institute of Cardiology “Ignacio Chavez,” Mexico City, Mexico
| | - Magdalena Madero
- Department of Nephrology, National Institute of Cardiology “Ignacio Chavez,” Mexico City, Mexico
| | - Bernardo Rodriguez-Iturbe
- Department of Nephrology, National Institute of Cardiology "Ignacio Chavez," Mexico City, Mexico .,Department of Nephrology and Mineral Metabolism, National Institute of Health Sciences and Nutrition "Salvador Zubirán," Mexico City, Mexico
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28
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Bushinsky DA, Krieger NS. Effects of Acid on Bone. Kidney Int 2022; 101:1160-1170. [DOI: 10.1016/j.kint.2022.02.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 02/25/2022] [Accepted: 02/28/2022] [Indexed: 12/11/2022]
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29
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Kim HJ. Metabolic Acidosis in Chronic Kidney Disease: Pathogenesis, Clinical Consequences, and Treatment. Electrolyte Blood Press 2021; 19:29-37. [PMID: 35003283 PMCID: PMC8715222 DOI: 10.5049/ebp.2021.19.2.29] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 12/03/2021] [Accepted: 12/06/2021] [Indexed: 12/13/2022] Open
Abstract
The kidneys play an important role in regulating the acid-base balance. Metabolic acidosis is common in chronic kidney disease (CKD) patients and can lead to poor outcomes, such as bone demineralization, muscle mass loss, and worsening of renal function. Metabolic acidosis is usually approached with evaluating the serum bicarbonate levels but should be assessed by counting blood pH. Current guidelines recommend oral bicarbonate supplementation to maintain the serum bicarbonate levels within the normal range. However, a slow decline in the glomerular filtration rate might occur, even though the serum bicarbonate levels were in the normal range. Because the serum bicarbonate levels decrease when metabolic acidosis advances, other biomarkers are necessary to indicate acid retention for early diagnosis of metabolic acidosis. For this, urine citrate and ammonium excretion may be used to follow the course of CKD patients. Metabolic acidosis can be treated with an increased fruit and vegetable intake and oral alkali supplementation. Previous studies have suggested that administration of oral sodium bicarbonate may preserve kidney function without significant increases in blood pressure and body weight. Veverimer, a non-absorbed, counterion-free, polymeric drug, is emerging to treat metabolic acidosis, but further researches are awaited. Further studies are also needed to clarify the target therapeutic range of serum bicarbonate and the drugs used for metabolic acidosis.
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Affiliation(s)
- Hyo Jin Kim
- Department of Internal Medicine, Pusan National University School of Medicine, Busan, Republic of Korea.,Biomedical Research Institute, Pusan National University Hospital, Busan, Republic of Korea
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30
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Adamczak M, Surma S. Metabolic Acidosis in Patients with CKD: Epidemiology, Pathogenesis, and Treatment. KIDNEY DISEASES (BASEL, SWITZERLAND) 2021; 7:452-467. [PMID: 34901192 DOI: 10.1159/000516371] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 04/02/2021] [Indexed: 02/01/2023]
Abstract
BACKGROUND Metabolic acidosis in CKD is diagnosed in patients with plasma or venous blood bicarbonate concentration lower than 22 mmol/L. Metabolic acidosis occurs in about 20% of patients with CKD. Metabolic acidosis may lead to dysfunction of many systems and organs as well as CKD progression. Currently, sodium bicarbonate is mainly used for pharmacological treatment of metabolic acidosis in patients with CKD. Veverimer is a new drug dedicated to treatment of metabolic acidosis in patients with CKD. Orally given veverimer binds hydrogen ions in the intestines and subsequently is excreted from the body with feces. Clinical studies have shown that veverimer is effective in increasing serum bicarbonate concentrations in CKD patients with metabolic acidosis. Here, we present review of the epidemiology, pathogenesis, diagnosis, treatment, and prevention of metabolic acidosis in CKD patients. SUMMARY Metabolic acidosis is common in patients with CKD and contributes to CKD progression and many complications, which worsen the prognosis in these patients. Currently, sodium bicarbonate is mainly used in metabolic acidosis treatment. The role of the new drug veverimer in the metabolic acidosis therapy needs further studies. KEY MESSAGE The aim of this review article is to summarize the current knowledge concerning the epidemiology, pathogenesis, diagnosis, treatment, and prevention of metabolic acidosis in CKD patients.
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Affiliation(s)
- Marcin Adamczak
- Department of Nephrology, Transplantation and Internal Medicine, Medical University of Silesia in Katowice, Katowice, Poland
| | - Stanisław Surma
- Department of Nephrology, Transplantation and Internal Medicine, Medical University of Silesia in Katowice, Katowice, Poland
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31
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Imenez Silva PH, Unwin R, Hoorn EJ, Ortiz A, Trepiccione F, Nielsen R, Pesic V, Hafez G, Fouque D, Massy ZA, De Zeeuw CI, Capasso G, Wagner CA. Acidosis, cognitive dysfunction and motor impairments in patients with kidney disease. Nephrol Dial Transplant 2021; 37:ii4-ii12. [PMID: 34718761 PMCID: PMC8713149 DOI: 10.1093/ndt/gfab216] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Indexed: 12/20/2022] Open
Abstract
Metabolic acidosis, defined as a plasma or serum bicarbonate concentration <22 mmol/L, is a frequent consequence of chronic kidney disease (CKD) and occurs in ~10–30% of patients with advanced stages of CKD. Likewise, in patients with a kidney transplant, prevalence rates of metabolic acidosis range from 20% to 50%. CKD has recently been associated with cognitive dysfunction, including mild cognitive impairment with memory and attention deficits, reduced executive functions and morphological damage detectable with imaging. Also, impaired motor functions and loss of muscle strength are often found in patients with advanced CKD, which in part may be attributed to altered central nervous system (CNS) functions. While the exact mechanisms of how CKD may cause cognitive dysfunction and reduced motor functions are still debated, recent data point towards the possibility that acidosis is one modifiable contributor to cognitive dysfunction. This review summarizes recent evidence for an association between acidosis and cognitive dysfunction in patients with CKD and discusses potential mechanisms by which acidosis may impact CNS functions. The review also identifies important open questions to be answered to improve prevention and therapy of cognitive dysfunction in the setting of metabolic acidosis in patients with CKD.
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Affiliation(s)
- Pedro H Imenez Silva
- Institute of Physiology, University of Zurich, Zürich, Switzerland.,National Center of Competence in Research NCCR Kidney.CH, Zürich, Switzerland
| | - Robert Unwin
- Department of Renal Medicine, Royal Free Hospital, University College London, London, UK
| | - Ewout J Hoorn
- Department of Internal Medicine, Erasmus Medical Center, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Alberto Ortiz
- Department of Nephrology and Hypertension, IIS-Fundacion Jimenez Diaz, Universidad Autonoma de Madrid, Madrid, Spain
| | - Francesco Trepiccione
- Biogem Institute of Molecular Biology and Genetics, Ariano Irpino, Italy.,Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli," Naples, Italy
| | - Rikke Nielsen
- Department of Biomedicine-Anatomy, University of Aarhus, Aarhus, Denmark
| | - Vesna Pesic
- Department of Physiology, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia
| | - Gaye Hafez
- Department of Pharmacology, Faculty of Pharmacy, Altinbas University, Istanbul, Turkey
| | - Denis Fouque
- CarMeN, INSERM 1060, Université Claude Bernard Lyon 1, Lyon, France.,Service de Néphrologie, Lyon-Sud Hospital, Pierre-Bénite, France
| | - Ziad A Massy
- Department of Nephrology, Ambroise Paré University Hospital, Assistance Publique Hôpitaux de Paris, Boulogne-Billancourt, France.,Centre de Recherche en Epidémiologie et Santé des Populations, Institut National de la Santé et de la Recherche Médicale U1018-Team 5, Université de Versailles Saint-Quentin-en-Yvelines, University Paris Saclay, Villejuif, France
| | - Chris I De Zeeuw
- Department of Neuroscience, Erasmus Medical Center, University Medical Center Rotterdam, Rotterdam, The Netherlands.,Netherlands Institute for Neuroscience, Royal Dutch Academy of Art and Science, Amsterdam, The Netherlands
| | - Giovambattista Capasso
- Biogem Institute of Molecular Biology and Genetics, Ariano Irpino, Italy.,Department of Translational Medical Sciences, University of Campania "Luigi Vanvitelli," Naples, Italy
| | - Carsten A Wagner
- Institute of Physiology, University of Zurich, Zürich, Switzerland.,National Center of Competence in Research NCCR Kidney.CH, Zürich, Switzerland
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32
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Beaume J, Figueres L, Bobot M, de Laforcade L, Ayari H, Dolley-Hitze T, Gueutin V, Braconnier A, Golbin L, Citarda S, Seret G, Belaïd L, Cohen R, Luque Y, Larceneux F, Seervai RNH, Overs C, Bertocchio JP. Sodium Bicarbonate Prescription and Extracellular Volume Increase: Real-world Data Results from the AlcalUN Study. Clin Pharmacol Ther 2021; 111:252-262. [PMID: 34564842 DOI: 10.1002/cpt.2427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 09/13/2021] [Indexed: 11/11/2022]
Abstract
Oral alkalization with sodium bicarbonate (NaHCO3 ) or citrate is prescribed for conditions ranging from metabolic acidosis to nephrolithiasis. Although most nephrologists/urologists use this method routinely, extracellular volume (ECV) increase is the main feared adverse event reported for NaHCO3 . Thus far, no trial has specifically studied this issue in a real-world setting. AlcalUN (NCT03035812) is a multicentric, prospective, open-label cohort study with nationwide (France) enrollment in 18 (public and private) nephrology/urology units. Participants were adult outpatients requiring chronic (>1 month) oral alkalization by either NaHCO3 -containing or no-NaHCO3 -containing agents. The ECV increase (primary outcome) was judged based on body weight increase (ΔBW), blood pressure increase (ΔBP), and/or new-onset edema at the first follow-up visit (V1). From February 2017 to February 2020, 156 patients were enrolled. After a median 106 days of treatment, 91 (72%) patients reached the primary outcome. They had lower systolic (135 (125, 141) vs. 141 (130, 150), P = 0.02) and diastolic (77 (67, 85) vs. 85 (73, 90), P = 0.03) BP values, a higher plasma chloride (106.0 (105.0, 109.0) vs. 105.0 (102.0, 107.0), P = 0.02) at baseline, and a less frequent history of nephrolithiasis (32 vs. 56%, P = 0.02). Patients experienced mainly slight ΔBP (< 10 mmHg). The primary outcome was not associated (P = 0.79) with the study treatment (129 received NaHCO3 and 27 received citrate). We subsequently developed three different models of propensity score matching; each confirmed our results. Chronic oral alkalization with NaHCO3 is no longer associated with an ECV increase compared to citrate in real-life settings.
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Affiliation(s)
- Julie Beaume
- AVODD, HIA Sainte-Anne, Toulon, France.,Club des Jeunes Néphrologues, Paris, France
| | - Lucile Figueres
- Club des Jeunes Néphrologues, Paris, France.,DIVAT Consortium, Nantes, France.,Service de Néphrologie et d'immunologie clinique, ITUN, CHU de Nantes, Université de Nantes, Nantes, France
| | - Mickaël Bobot
- Club des Jeunes Néphrologues, Paris, France.,Centre de Néphrologie et Transplantation Rénale, Assistance Publique Hôpitaux de Marseille, Hôpital de la Conception, Marseille, France.,C2VN, INSERM 1263, INRAE 1260, Aix-Marseille Université, Marseille, France
| | - Louis de Laforcade
- Club des Jeunes Néphrologues, Paris, France.,Service Endocrinologie-Néphrologie, Centre Hospitalier Pierre Oudot, Bourgoin-Jallieu, France
| | - Hamza Ayari
- Renal and Metabolic Diseases Unit, European Georges Pompidou Hospital, AP-HP, Paris, France
| | - Thibault Dolley-Hitze
- Club des Jeunes Néphrologues, Paris, France.,Unité de dialyse de Saint-Malo, Fondation AUB Santé, Saint-Malo, France
| | - Victor Gueutin
- Service de Néphrologie-Dialyse, AURA Paris Plaisance, Paris, France.,Service de Néphrologie, Hôpital de La Pitié-Salpêtrière, AP-HP, Paris, France
| | - Antoine Braconnier
- Club des Jeunes Néphrologues, Paris, France.,Service de Néphrologie, Dialyse et Transplantation Rénale, CHU Reims, Hôpital Maison Blanche, Reims, France
| | - Léonard Golbin
- Club des Jeunes Néphrologues, Paris, France.,Service de Néphrologie, Dialyse et Transplantation Rénale, CHU Rennes, Hôpital Pontchaillou, Rennes, France
| | - Salvatore Citarda
- Club des Jeunes Néphrologues, Paris, France.,Centre associatif lyonnais de dialyse (Calydial), Irigny, France
| | | | - Lisa Belaïd
- Unité de dialyse de Saint-Malo, Fondation AUB Santé, Saint-Malo, France
| | - Raphaël Cohen
- Renal and Metabolic Diseases Unit, European Georges Pompidou Hospital, AP-HP, Paris, France
| | - Yosu Luque
- Club des Jeunes Néphrologues, Paris, France.,Urgences Néphrologiques et Transplantation Rénale, Hôpital Tenon, AP-HP, UMR_S1155, Sorbonne Université, Paris, France
| | - Fabrice Larceneux
- CNRS, UMR (7088), DRM, (ERMES), Université Paris-Dauphine, PSL Research University, Paris, France
| | - Riyad N H Seervai
- Center for Precision Environmental Health, Baylor College of Medicine, Houston, Texas, USA.,Molecular & Cellular Biology Graduate Program, Medical Scientist Training Program, Baylor College of Medicine, Houston, Texas, USA
| | - Camille Overs
- Association Française des Urologues en Formation, Paris, France.,Service d'Urologie, Andrologie et transplantation Rénale, CHU de Grenoble, La Tronche, France
| | - Jean-Philippe Bertocchio
- Club des Jeunes Néphrologues, Paris, France.,Service de Néphrologie, Hôpital de La Pitié-Salpêtrière, AP-HP, Paris, France
| | -
- Club des Jeunes Néphrologues, Paris, France
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33
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Borrego Utiel FJ, Herrera Contreras I, Merino García E, Moriana Domínguez C, Ocaña Pérez E, García Cortés MJ. Hypocitraturia is present when renal function is impaired in diverse nephropathies and is not related with serum bicarbonate levels. Int Urol Nephrol 2021; 54:1261-1269. [PMID: 34546556 DOI: 10.1007/s11255-021-02992-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 08/02/2021] [Indexed: 12/01/2022]
Abstract
BACKGROUND In autosomal dominant polycystic kidney disease (ADPKD) it is frequently found a reduction in urinary citrate of unknown origin. It has been suggested that it could be a marker of acid retention in chronic kidney disease. Our aim was to compare urinary citrate in ADPKD with other nephropathies and to show its relation with serum bicarbonate. METHODS We determined urinary citrate in patients with several nephropathies and varied renal function. We included 291 patients, 119 with glomerular diseases, 116 with ADPKD, 21 with other nephropathies, and 35 patients with normal renal function. RESULTS Urinary citrate was higher in women and in patients with normal renal function. ADPKD patients showed similar values of urinary citrate to patients with glomerular diseases and with other nephropathies. We observed a progressive reduction in urinary citrate with renal impairment, in a comparable way among patients with ADPKD and glomerular diseases. We did not observe a relationship with serum bicarbonate. Serum uric acid levels were significantly higher in patients with glomerular diseases than in ADPKD patients, even after correction with the degree of renal function. CONCLUSIONS Hypocitraturia is not specific of ADPKD but it is also present in all tested nephropathies and is related with renal impairment and not with serum bicarbonate. It could be interesting to study urinary citrate as a marker of renal function and as a prognostic factor.
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Affiliation(s)
| | | | - Enoc Merino García
- Unidad de Gestión Clínica (UGC) de Nefrología, Hospital Universitario de Jaén, Jaén, Spain
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34
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Quek DQY, He F, Sultana R, Banu R, Chee ML, Nusinovici S, Thakur S, Qian C, Cheng CY, Wong TY, Sabanayagam C. Novel Serum and Urinary Metabolites Associated with Diabetic Retinopathy in Three Asian Cohorts. Metabolites 2021; 11:metabo11090614. [PMID: 34564429 PMCID: PMC8467425 DOI: 10.3390/metabo11090614] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 09/01/2021] [Accepted: 09/03/2021] [Indexed: 11/16/2022] Open
Abstract
Diabetic retinopathy (DR) is a microvascular complication of diabetes mellitus, a metabolic disorder, but understanding of its pathophysiology remains incomplete. Meta-analysis of three population-based cross-sectional studies (2004–11) representing three major Asian ethnic groups (aged 40–80 years: Chinese, 592; Malays, 1052; Indians, 1320) was performed. A panel of 228 serum/plasma metabolites and 54 urinary metabolites were quantified using nuclear magnetic resonance (NMR) spectroscopy. Main outcomes were defined as any DR, moderate/above DR, and vision-threatening DR assessed from retinal photographs. The relationship between metabolites and DR outcomes was assessed using multivariate logistic regression models, and metabolites significant after Bonferroni correction were meta-analyzed. Among serum/plasma metabolites, lower levels of tyrosine and cholesterol esters to total lipids ratio in IDL and higher levels of creatinine were positively associated with all three outcomes of DR (all p < 0.005). Among urinary metabolites, lower levels of citrate, ethanolamine, formate, and hypoxanthine were positively associated with all three DR outcomes (all p < 0.005). Higher levels of serum/plasma 3-hydroxybutyrate and lower levels of urinary 3-hydroxyisobutyrate were associated with VTDR. Comprehensive metabolic profiling in three large Asian cohorts with DR demonstrated alterations in serum/plasma and urinary metabolites mostly related to amino acids, lipoprotein subclasses, kidney function, and glycolysis.
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Affiliation(s)
- Debra Q. Y. Quek
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore; (D.Q.Y.Q.); (F.H.); (R.B.); (M.L.C.); (S.N.); (S.T.); (C.Q.); (C.-Y.C.); (T.Y.W.)
| | - Feng He
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore; (D.Q.Y.Q.); (F.H.); (R.B.); (M.L.C.); (S.N.); (S.T.); (C.Q.); (C.-Y.C.); (T.Y.W.)
| | - Rehena Sultana
- Centre for Quantitative Medicine, Duke-NUS Medical School, Singapore 169857, Singapore;
| | - Riswana Banu
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore; (D.Q.Y.Q.); (F.H.); (R.B.); (M.L.C.); (S.N.); (S.T.); (C.Q.); (C.-Y.C.); (T.Y.W.)
| | - Miao Li Chee
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore; (D.Q.Y.Q.); (F.H.); (R.B.); (M.L.C.); (S.N.); (S.T.); (C.Q.); (C.-Y.C.); (T.Y.W.)
| | - Simon Nusinovici
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore; (D.Q.Y.Q.); (F.H.); (R.B.); (M.L.C.); (S.N.); (S.T.); (C.Q.); (C.-Y.C.); (T.Y.W.)
| | - Sahil Thakur
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore; (D.Q.Y.Q.); (F.H.); (R.B.); (M.L.C.); (S.N.); (S.T.); (C.Q.); (C.-Y.C.); (T.Y.W.)
| | - Chaoxu Qian
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore; (D.Q.Y.Q.); (F.H.); (R.B.); (M.L.C.); (S.N.); (S.T.); (C.Q.); (C.-Y.C.); (T.Y.W.)
| | - Ching-Yu Cheng
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore; (D.Q.Y.Q.); (F.H.); (R.B.); (M.L.C.); (S.N.); (S.T.); (C.Q.); (C.-Y.C.); (T.Y.W.)
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
| | - Tien Y. Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore; (D.Q.Y.Q.); (F.H.); (R.B.); (M.L.C.); (S.N.); (S.T.); (C.Q.); (C.-Y.C.); (T.Y.W.)
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
| | - Charumathi Sabanayagam
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore 168751, Singapore; (D.Q.Y.Q.); (F.H.); (R.B.); (M.L.C.); (S.N.); (S.T.); (C.Q.); (C.-Y.C.); (T.Y.W.)
- Ophthalmology and Visual Sciences Academic Clinical Program, Duke-NUS Medical School, Singapore 169857, Singapore
- Correspondence: ; Tel.: +65-6576-7286; Fax: +65-6225-2568
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35
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Involvement of Tricarboxylic Acid Cycle Metabolites in Kidney Diseases. Biomolecules 2021; 11:biom11091259. [PMID: 34572472 PMCID: PMC8465464 DOI: 10.3390/biom11091259] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 08/17/2021] [Accepted: 08/23/2021] [Indexed: 02/08/2023] Open
Abstract
Mitochondria are complex organelles that orchestrate several functions in the cell. The primary function recognized is energy production; however, other functions involve the communication with the rest of the cell through reactive oxygen species (ROS), calcium influx, mitochondrial DNA (mtDNA), adenosine triphosphate (ATP) levels, cytochrome c release, and also through tricarboxylic acid (TCA) metabolites. Kidney function highly depends on mitochondria; hence mitochondrial dysfunction is associated with kidney diseases. In addition to oxidative phosphorylation impairment, other mitochondrial abnormalities have been described in kidney diseases, such as induction of mitophagy, intrinsic pathway of apoptosis, and releasing molecules to communicate to the rest of the cell. The TCA cycle is a metabolic pathway whose primary function is to generate electrons to feed the electron transport system (ETS) to drives energy production. However, TCA cycle metabolites can also release from mitochondria or produced in the cytosol to exert different functions and modify cell behavior. Here we review the involvement of some of the functions of TCA metabolites in kidney diseases.
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Abstract
Small-scale trials in patients with chronic kidney disease (CKD) 3-5 have shown that hypobicarbonatemic metabolic acidosis promotes progression of CKD. Accordingly, the 2012 KDIGO (Kidney Disease: Improving Global Outcomes) guideline suggests base administration to patients with CKD when serum bicarbonate concentration ([HCO3ˉ]) is <22 mEq/L (~15% of non–dialysis-dependent patients with CKD). However, individuals with milder CKD largely maintain serum [HCO3ˉ] within the normal range (eubicarbonatemia) and yet can manifest hydrogen ion (H+) retention. Limited data in eubicarbonatemic patients with CKD 2 suggest that base administration ameliorates CKD progression. Furthermore, most patients with moderate and advanced CKD maintain a normal serum [HCO3ˉ], and of those, the vast majority most likely harbor masked H+ retention. The present review probes this expanded concept of metabolic acidosis of CKD: the eubicarbonatemic H+ retention or subclinical metabolic acidosis of CKD. It focuses on the high prevalence of the entity, its pathophysiologic features, its clinical course, and recent work on potential biomarkers of the condition. Further, it puts forward the urgent task of investigating definitively whether treatment with alkali of eubicarbonatemic H+ retention delays CKD progression. If proven true, such knowledge would trigger a paradigm shift in the indication for alkali therapy in CKD.
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Affiliation(s)
- Nicolaos E Madias
- Department of Medicine, Tufts University School of Medicine and Division of Nephrology, Department of Medicine, St. Elizabeth's Medical Center, Boston, MA
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Abstract
Acid-related injury from chronic metabolic acidosis is recognized through growing evidence of its deleterious effects, including kidney and other organ injury. Progressive acid accumulation precedes the signature manifestation of chronic metabolic acidosis, decreased plasma bicarbonate concentration. Acid accumulation that is not enough to manifest as metabolic acidosis, known as eubicarbonatemic acidosis, also appears to cause kidney injury, with exacerbated progression of CKD. Chronic engagement of mechanisms to mitigate the acid challenge from Western-type diets also appears to cause kidney injury. Rather than considering chronic metabolic acidosis as the only acid-related condition requiring intervention to reduce kidney injury, this review supports consideration of acid-related injury as a continuum. This "acid stress" continuum has chronic metabolic acidosis at its most extreme end, and high-acid-producing diets at its less extreme, yet detrimental, end.
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Affiliation(s)
- Donald E. Wesson
- Department of Internal Medicine, Texas A&M Health Science Center College of Medicine, Dallas, Texas
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Urinary citrate as a marker of renal function in patients with autosomal dominant polycystic kidney disease. Int Urol Nephrol 2021; 54:873-881. [PMID: 34279821 DOI: 10.1007/s11255-021-02953-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 07/07/2021] [Indexed: 10/20/2022]
Abstract
INTRODUCTION Autosomal dominant polycystic kidney disease (ADPKD) is frequent to find low urinary citrate levels. Recently, it has been suggested that urinary citrate could be a marker of covert metabolic acidosis in chronic kidney disease. OBJECTIVE Our aim was to analyze relationship between urinary citrate levels, renal function, and serum bicarbonate in ADPKD patients. METHODS We determined citrate in 24-h collected urine from ADPKD patients and correlated with glomerular filtration rate (CKD-EPI equation) and serum bicarbonate concentration. RESULTS We included 120 patients, 60% men, eGFR was 71 ± 32 mL/min/1.73 m2. Urinary citrate/creatinine ratio was 195 ± 152 mg/gCr (range 1.2-689) with levels significantly higher in females. Urinary citrate lower than 300 mg/gCr was present in 75% of patients and when considering chronic kidney stages (CKD), we observed reduced levels in 48.8% in CKD1 stage, in 79.4% in CKD2 stage, in 96.2% in CKD3 stage, and in 94.7% of patients in CKD4 stage. Urinary citrate was correlated with serum creatinine (r = - 0.61, p < 0.001) and eGFR (r = 0.55, p < 0.001) in both gender. We did not find any correlation with serum bicarbonate. Using a general linear modeling analysis, we found as predictors of urinary citrate/creatinine ratio to glomerular filtration rate, gender, and age. Lower levels of urinary citrate were accompanied by a decline in urinary osmolality and in renal excretion of calcium and uric acid. In a subgroup of patients, we measured total kidney volume and we found an inverse correlation with urinary citrate levels that disappeared when it was corrected with glomerular filtration rate. CONCLUSIONS Urinary citrate is very frequently reduced in ADPKD patients being present from very early CKD stages. Their levels in urine are inversely correlated with glomerular filtration rate and it is not related with serum bicarbonate concentration. We think that it would be interesting to study urinary citrate as a marker of chronic kidney disease in ADPKD patients.
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Silva PHI, Wiegand A, Daryadel A, Russo G, Ritter A, Gaspert A, Wüthrich RP, Wagner CA, Mohebbi N. Acidosis and alkali therapy in patients with kidney transplant is associated with transcriptional changes and altered abundance of genes involved in cell metabolism and acid-base balance. Nephrol Dial Transplant 2021; 36:1806-1820. [PMID: 34240183 DOI: 10.1093/ndt/gfab210] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Metabolic acidosis occurs frequently in patients with kidney transplant and is associated with higher risk for and accelerated loss of graft function. To date, it is not known whether alkali therapy in these patients improves kidney function and whether acidosis and its therapy is associated with altered expression of proteins involved in renal acid-base metabolism. METHODS We collected retrospectively kidney biopsies from 22 patients. Of these patients, 9 had no acidosis, 9 had metabolic acidosis (plasma HCO3- < 22 mmol/l), and 4 had acidosis and received alkali therapy. We performed transcriptome analysis and immunohistochemistry for proteins involved in renal acid-base handling. RESULTS We found the expression of 40 transcripts significantly changed between kidneys from non-acidotic and acidotic patients. These genes are mostly involved in proximal tubule amino acid and lipid metabolism and energy homeostasis. Three transcripts were fully recovered by alkali therapy: the Kir4.2 K+-channel, an important regulator of proximal tubule HCO3--metabolism and transport, ACADSB and SHMT1, genes involved in beta-oxidation and methionine metabolism. Immunohistochemistry showed reduced staining for the proximal tubule NBCe1 HCO3- transporter in kidneys from acidotic patients that recovered with alkali therapy. In addition, the HCO3-exchanger pendrin was affected by acidosis and alkali therapy. CONCLUSIONS Metabolic acidosis in kidney transplant recipients is associated with alterations in the renal transcriptome that are partly restored by alkali therapy. Acid-base transport proteins mostly from proximal tubule were also affected by acidosis and alkali therapy suggesting that the downregulation of critical players contributes to metabolic acidosis in these patients.
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Affiliation(s)
- Pedro H Imenez Silva
- Institute of Physiology, University of Zurich, Zurich, Switzerland.,National Center of Competence in Research NCCR Kidney.CH, Switzerland
| | - Anna Wiegand
- Division of Nephrology, University Hospital Zurich, Zurich, Switzerland
| | - Arezoo Daryadel
- Institute of Physiology, University of Zurich, Zurich, Switzerland.,National Center of Competence in Research NCCR Kidney.CH, Switzerland
| | - Giancarlo Russo
- Functional Genomics Center Zürich, University of Zürich and ETH Zürich, Zürich, Switzerland
| | - Alexander Ritter
- Division of Nephrology, University Hospital Zurich, Zurich, Switzerland
| | - Ariana Gaspert
- Department of Pathology and Molecular Pathology, University Hospital Zurich, Zurich, Switzerland
| | - Rudolf P Wüthrich
- Division of Nephrology, University Hospital Zurich, Zurich, Switzerland
| | - Carsten A Wagner
- Institute of Physiology, University of Zurich, Zurich, Switzerland.,National Center of Competence in Research NCCR Kidney.CH, Switzerland
| | - Nilufar Mohebbi
- Division of Nephrology, University Hospital Zurich, Zurich, Switzerland
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Bargagli M, Moochhala S, Robertson WG, Gambaro G, Lombardi G, Unwin RJ, Ferraro PM. Urinary metabolic profile and stone composition in kidney stone formers with and without heart disease. J Nephrol 2021; 35:851-857. [PMID: 34152561 PMCID: PMC8995244 DOI: 10.1007/s40620-021-01096-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 06/09/2021] [Indexed: 11/09/2022]
Abstract
Objective Kidney stone disease seems to be associated with an increased risk of incident cardiovascular outcomes; the aim of this study is to identify differences in 24-h urine excretory profiles and stone composition among stone formers with and without cardiovascular disease (CVD). Methods Data from patients attending the Department of Renal Medicine’s metabolic stone clinic from 1995 to 2012 were reviewed. The sample was divided according to the presence or absence of CVD (myocardial infarction, angina, coronary revascularization, or surgery for calcified heart valves). Univariable and multivariable regression models, adjusted for age, sex, BMI, hypertension, diabetes, eGFR, plasma bicarbonate and potential renal acid load of foods were used to investigate differences across groups. Results 1826 patients had available data for 24-h urine analysis. Among these, 108 (5.9%) had a history of CVD. Those with CVD were older, have higher prevalence of hypertension and diabetes and lower eGFR. Univariable analysis showed that patients with CVD had significantly lower 24-h urinary excretions for citrate (2.4 vs 2.6 mmol/24 h, p = 0.04), magnesium (3.9 vs 4.2 mmol/24 h, p = 0.03) and urinary pH (6.1 vs 6.2, p = 0.02). After adjustment for confounders, differences in urinary citrate and magnesium excretions remained significant. No differences in the probability of stone formation or stone compositions were found. Conclusions Stone
formers with CVD have lower renal alkali excretion, possibly suggesting higher
acid retention in stone formers with cardiovascular comorbidities. Randomized
clinical trials including medications and a controlled diet design are needed
to confirm the results presented here. Graphic abstract ![]()
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Affiliation(s)
- Matteo Bargagli
- U.O.S. Terapia Conservativa della Malattia Renale Cronica, U.O.C. Nefrologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Largo Agostino Gemelli 8, 00168, Rome, Italy
| | - Shabbir Moochhala
- Department of Renal Medicine, Royal Free Campus Medical School, University College Hospital, London, UK
| | - William G Robertson
- Department of Renal Medicine, Royal Free Campus Medical School, University College Hospital, London, UK
- Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK
| | - Giovanni Gambaro
- Renal Unit, Division of Nephrology and Dialysis, Department of Medicine, University of Verona, Verona, Italy
| | - Gianmarco Lombardi
- Renal Unit, Division of Nephrology and Dialysis, Department of Medicine, University of Verona, Verona, Italy
| | - Robert J Unwin
- Department of Renal Medicine, Royal Free Campus Medical School, University College Hospital, London, UK
| | - Pietro Manuel Ferraro
- U.O.S. Terapia Conservativa della Malattia Renale Cronica, U.O.C. Nefrologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, Università Cattolica del Sacro Cuore, Largo Agostino Gemelli 8, 00168, Rome, Italy.
- Dipartimento Universitario di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, Rome, Italy.
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Kraut JA, Raphael KL. Assessment of Acid-Base Status: Beyond Serum Bicarbonate. Clin J Am Soc Nephrol 2021; 16:1429-1431. [PMID: 34088720 PMCID: PMC8729583 DOI: 10.2215/cjn.02760221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Jeffrey A Kraut
- Medical and Research Services Veterans Administration Greater Los Angeles Healthcare System and Division of Nephrology Veterans Administration Greater Los Angeles Healthcare System, University of California, Los Angeles Membrane Biology Laboratory and University of California, Los Angeles David Geffen School of Medicine Sciences, Los Angeles, California
| | - Kalani L Raphael
- Division of Nephrology & Hypertension, Department of Medicine, Oregon Health & Science University and Veterans Affairs Portland Health Care System, Portland, Oregon
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Pietrobom I, Heilberg IP. The necessary pathway for metabolic and crystallographic analysis of kidney stones: struvite may not differ from its counterparts. J Bras Nefrol 2021; 43:152-153. [PMID: 34032818 PMCID: PMC8257270 DOI: 10.1590/2175-8239-jbn-2021-e004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 04/14/2021] [Indexed: 11/22/2022] Open
Affiliation(s)
- Igor Pietrobom
- Universidade Federal de São Paulo, Escola Paulista de Medicina, São Paulo, SP, Brasil
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Effect of Tolvaptan Treatment on Acid-Base Homeostasis in ADPKD Patients. Kidney Int Rep 2021; 6:1749. [PMID: 34169219 PMCID: PMC8207303 DOI: 10.1016/j.ekir.2021.04.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 04/05/2021] [Indexed: 11/23/2022] Open
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Wesson DE. Sodium zirconium cyclosilicate for hyperkalemia: a collateral acid-base benefit? Nephrol Dial Transplant 2021; 36:756-760. [PMID: 33179742 DOI: 10.1093/ndt/gfaa241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 08/25/2020] [Indexed: 11/14/2022] Open
Affiliation(s)
- Donald E Wesson
- Department of Internal Medicine, Texas A&M College of Medicine, Dallas, TX, USA
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45
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Tyson CC, Luciano A, Modliszewski JL, Corcoran DL, Bain JR, Muehlbauer M, Ilkayeva O, Pourafshar S, Allen J, Bowman C, Gung J, Asplin JR, Pendergast J, Svetkey LP, Lin PH, Scialla JJ. Effect of Bicarbonate on Net Acid Excretion, Blood Pressure, and Metabolism in Patients With and Without CKD: The Acid Base Compensation in CKD Study. Am J Kidney Dis 2021; 78:38-47. [PMID: 33810868 DOI: 10.1053/j.ajkd.2020.10.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Accepted: 10/10/2020] [Indexed: 11/11/2022]
Abstract
RATIONALE & OBJECTIVE Patients with CKD are at elevated risk of metabolic acidosis due to impaired net acid excretion (NAE). Identifying early markers of acidosis may guide prevention in chronic kidney disease (CKD). This study compared NAE in participants with and without CKD, as well as the NAE, blood pressure (BP), and metabolomic response to bicarbonate supplementation. STUDY DESIGN Randomized order, cross-over study with controlled feeding. SETTING & PARTICIPANTS Participants consisted of 8 patients with CKD (estimated glomerular filtration rate 30-59mL/min/1.73m2 or 60-70mL/min/1.73m2 with albuminuria) and 6 patients without CKD. All participants had baseline serum bicarbonate concentrations between 20 and 28 mEq/L; they did not have diabetes mellitus and did not use alkali supplements at baseline. INTERVENTION Participants were fed a fixed-acid-load diet with bicarbonate supplementation (7 days) and with sodium chloride control (7 days) in a randomized order, cross-over fashion. OUTCOMES Urine NAE, 24-hour ambulatory BP, and 24-hour urine and plasma metabolomic profiles were measured after each period. RESULTS During the control period, mean NAE was 28.3±10.2 mEq/d overall without differences across groups (P=0.5). Urine pH, ammonium, and citrate were significantly lower in CKD than in non-CKD (P<0.05 for each). Bicarbonate supplementation reduced NAE and urine ammonium in the CKD group, increased urine pH in both groups (but more in patients with CKD than in those without), and increased; urine citrate in the CKD group (P< 0.2 for interaction for each). Metabolomic analysis revealed several urine organic anions were increased with bicarbonate in CKD, including 3-indoleacetate, citrate/isocitrate, and glutarate. BP was not significantly changed. LIMITATIONS Small sample size and short feeding duration. CONCLUSIONS Compared to patients without CKD, those with CKD had lower acid excretion in the form of ammonium but also lower base excretion such as citrate and other organic anions, a potential compensation to preserve acid-base homeostasis. In CKD, acid excretion decreased further, but base excretion (eg, citrate) increased in response to alkali. Urine citrate should be evaluated as an early and responsive marker of impaired acid-base homeostasis. FUNDING National Institute of Diabetes and Digestive and Kidney Diseases and the Duke O'Brien Center for Kidney Research. TRIAL REGISTRATION Registered at ClinicalTrials.gov with study number NCT02427594.
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Affiliation(s)
- Crystal C Tyson
- Department of Medicine, Duke University School of Medicine, Durham, NC
| | - Alison Luciano
- Center for the Study of Aging and Human Development, Duke University School of Medicine, Durham, NC
| | - Jennifer L Modliszewski
- Center for Genomic and Computational Biology, Duke University School of Medicine, Durham, NC; Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, NC
| | - David L Corcoran
- Center for Genomic and Computational Biology, Duke University School of Medicine, Durham, NC; Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, NC
| | - James R Bain
- Department of Medicine, Duke University School of Medicine, Durham, NC; Center for the Study of Aging and Human Development, Duke University School of Medicine, Durham, NC; Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, NC
| | - Michael Muehlbauer
- Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, NC
| | - Olga Ilkayeva
- Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, NC
| | - Shirin Pourafshar
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA
| | - Jenifer Allen
- Department of Medicine, Duke University School of Medicine, Durham, NC
| | - Cassandra Bowman
- Department of Medicine, Duke University School of Medicine, Durham, NC
| | - Joseph Gung
- Department of Medicine, Duke University School of Medicine, Durham, NC
| | - John R Asplin
- Litholink Corp, Laboratory Corporation of America Holdings, Chicago, IL
| | - Jane Pendergast
- Department of Medicine, Duke University School of Medicine, Durham, NC; Center for the Study of Aging and Human Development, Duke University School of Medicine, Durham, NC; Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, NC
| | - Laura P Svetkey
- Department of Medicine, Duke University School of Medicine, Durham, NC; Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, NC
| | - Pao-Hwa Lin
- Department of Medicine, Duke University School of Medicine, Durham, NC; Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, NC
| | - Julia J Scialla
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA.
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Tran TVM, Li X, Adams-Huet B, Maalouf NM. Impact of age and renal function on urine chemistry in patients with calcium oxalate kidney stones. Urolithiasis 2021; 49:495-504. [PMID: 33582830 DOI: 10.1007/s00240-021-01254-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 01/30/2021] [Indexed: 12/22/2022]
Abstract
Nephrolithiasis is associated with an increased risk of chronic kidney disease, and its incidence varies with age. However, little is known on the combined impact of aging and declining renal function on urinary risk factors for calcium oxalate stone formation. A retrospective analysis was performed on 24-h urine collections from 993 calcium oxalate stone-forming patients. We first tested for interactions between age and creatinine clearance on various urinary determinants of calcium oxalate nephrolithiasis, and then examined their separate and combined effects in univariable and multivariable analyses adjusting for demographic and biochemical covariates. We identified significant interactions between age and creatinine clearance in predicting 24-h urine pH, calcium, and citrate. In view of the small number of stone formers with low creatinine clearance, we limited further regression analyses to patients with creatinine clearance ≥ 60 mL/min. In multivariable analyses, urine citrate, oxalate, and total volume were positively correlated with age, whereas urine pH, citrate, calcium, oxalate, total volume, and RSR of calcium oxalate all significantly decreased with lower creatinine clearance. A decrease in creatinine clearance from 120 to 60 mL/min was associated with clinically significant decreases in the daily excretion rate of citrate (by 188 mg/day), calcium (by 33 mg/day), and oxalate (by 4 mg/day), and in RSR calcium oxalate (by 1.84). Age and creatinine clearance are significant and independent predictors of several urinary determinants of calcium oxalate nephrolithiasis. The impacts of aging and declining renal function should be considered during the management of calcium oxalate stone-forming patients.
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Affiliation(s)
- Triet Vincent M Tran
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, UT Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-8885, USA
| | - Xilong Li
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, UT Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-8885, USA.,Department of Population and Data Sciences, UT Southwestern Medical Center, Dallas, TX, USA
| | - Beverley Adams-Huet
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, UT Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-8885, USA.,Department of Population and Data Sciences, UT Southwestern Medical Center, Dallas, TX, USA
| | - Naim M Maalouf
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, UT Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX, 75390-8885, USA. .,Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, USA.
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47
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Affiliation(s)
- Nicolaos E Madias
- Department of Medicine, Tufts University School of Medicine, Boston, Massachusetts
- Division of Nephrology, Department of Medicine, St. Elizabeth's Medical Center, Boston, Massachusetts
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48
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Yoo KD, An JN, Kim YC, Lee J, Joo KW, Oh YK, Kim YS, Lim CS, Oh S, Lee JP. Low serum total CO 2 and its association with mortality in patients being followed up in the nephrology outpatients clinic. Sci Rep 2021; 11:1711. [PMID: 33462380 PMCID: PMC7814051 DOI: 10.1038/s41598-021-81332-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 12/31/2020] [Indexed: 11/13/2022] Open
Abstract
Large-scale studies have not been conducted to assess whether serum hypobicarbonatemia increases the risk for kidney function deterioration and mortality among East-Asians. We aimed to determine the association between serum total CO2 (TCO2) concentrations measured at the first outpatient visit and clinical outcomes. In this multicenter cohort study, a total of 42,231 adult nephrology outpatients from 2001 to 2016 were included. End-stage renal disease (ESRD) patients on dialysis within 3 months of the first visit were excluded. Instrumental variable (IV) was used to define regions based on the proportion of patients with serum TCO2 < 22 mEq/L. The crude mortality rate was 12.2% during a median 77.0-month follow-up period. The Cox-proportional hazard regression model adjusted for initial kidney function, alkali supplementation, and the use of diuretics demonstrated that low TCO2 concentration was not associated with progression to ESRD, but significantly increased the risk of death. The IV analysis also confirmed a significant association between initial TCO2 concentration and mortality (HR 0.56; 95% CI 0.49–0.64). This result was consistently significant regardless of the underlying renal function. In conclusion, low TCO2 levels are significantly associated with mortality but not with progression to ESRD in patients with ambulatory care.
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Affiliation(s)
- Kyung Don Yoo
- Department of Internal Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Korea
| | - Jung Nam An
- Department of Internal Medicine, Hallym University Sacred Heart Hospital, Anyang, Gyeonggi-do, Korea
| | - Yong Chul Kim
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
| | - Jeonghwan Lee
- Department of Internal Medicine, Seoul National University Boramae Medical Center, 20, Boramae-ro 5-gil, Dongjak-gu, Seoul, 07061, Korea
| | - Kwon-Wook Joo
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.,Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Yun Kyu Oh
- Department of Internal Medicine, Seoul National University Boramae Medical Center, 20, Boramae-ro 5-gil, Dongjak-gu, Seoul, 07061, Korea.,Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Yon Su Kim
- Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.,Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Chun Soo Lim
- Department of Internal Medicine, Seoul National University Boramae Medical Center, 20, Boramae-ro 5-gil, Dongjak-gu, Seoul, 07061, Korea.,Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Sohee Oh
- Department of Biostatistics, Seoul National University Boramae Medical Center, 20, Boramae-ro 5-gil, Dongjak-gu, Seoul, 07061, Korea.
| | - Jung Pyo Lee
- Department of Internal Medicine, Seoul National University Boramae Medical Center, 20, Boramae-ro 5-gil, Dongjak-gu, Seoul, 07061, Korea. .,Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
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Monitoring acid base status in CKD patients: can urinary citrate help? Kidney Int 2021; 99:28-31. [PMID: 33390237 DOI: 10.1016/j.kint.2020.09.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 09/14/2020] [Accepted: 09/15/2020] [Indexed: 11/20/2022]
Abstract
Metabolic acidosis is an early and deleterious complication of chronic kidney disease. Because it is frequently eubicarbonatemic, diagnosis may be difficult. In this issue, Gianella et al. suggest that lower urinary citrate excretion, considered as an homeostatic response to metabolic acidosis, may be helpful for early diagnosis and monitoring of alkali treatment. This study should be an incentive for further assessment of the tubular handling of urinary citrate in CKD patients and determination of the performance of urinary citrate for the diagnosis of eubicarbonatemic metabolic acidosis and monitoring of alkali therapy.
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50
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Ottka C, Vapalahti K, Määttä A, Huuskonen N, Sarpanen S, Jalkanen L, Lohi H. High serum creatinine concentration is associated with metabolic perturbations in dogs. J Vet Intern Med 2021; 35:405-414. [PMID: 33349961 PMCID: PMC7848334 DOI: 10.1111/jvim.16011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 12/08/2020] [Accepted: 12/08/2020] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND The kidneys have many essential metabolic functions, and metabolic disturbances during decreased renal function have not been studied extensively. OBJECTIVES To identify metabolic changes in blood samples with increased serum creatinine concentration, indicating decreased glomerular filtration. ANIMALS Clinical samples analyzed using a nuclear magnetic resonance (NMR) based metabolomics platform. The case group consisted of 23 samples with serum creatinine concentration >125 μmol/L, and the control group of 873 samples with serum creatinine concentration within the reference interval. METHODS Biomarker association with increased serum creatinine concentration was evaluated utilizing 3 statistical approaches: Wilcoxon rank-sum test, logistic regression analysis (false discovery rate (FDR)-corrected P-values), and random forest classification. Medians of the biomarkers were compared to reference intervals. A heatmap and box plots were used to represent the differences. RESULTS All 3 statistical approaches identified similar analytes associated with increased serum creatinine concentrations. The percentages of citrate, tyrosine, branched-chain amino acids, valine, leucine, albumin, linoleic acid and the ratio of phenylalanine to tyrosine differed significantly using all statistical approaches, acetate differed using the Wilcoxon test and random forest, docosapentaenoic acid percentage only using logistic regression (P < .05), and alanine only using random forest. CONCLUSIONS AND CLINICAL IMPORTANCE We identified several metabolic changes associated with increased serum creatinine concentrations, including prospective diagnostic markers and therapeutic targets. Further research is needed to verify the association of these changes with the clinical state of the dog. The NMR metabolomics test is a promising tool for improving diagnostic testing and management of renal diseases in dogs.
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Affiliation(s)
- Claudia Ottka
- PetMeta Labs LtdHelsinkiFinland
- Department of Veterinary BiosciencesUniversity of HelsinkiHelsinkiFinland
- Department of Medical and Clinical GeneticsUniversity of HelsinkiHelsinkiFinland
- Folkhälsan Research CenterHelsinkiFinland
| | - Katariina Vapalahti
- PetMeta Labs LtdHelsinkiFinland
- Department of Veterinary BiosciencesUniversity of HelsinkiHelsinkiFinland
- Department of Medical and Clinical GeneticsUniversity of HelsinkiHelsinkiFinland
- Folkhälsan Research CenterHelsinkiFinland
| | | | | | | | | | - Hannes Lohi
- PetMeta Labs LtdHelsinkiFinland
- Department of Veterinary BiosciencesUniversity of HelsinkiHelsinkiFinland
- Department of Medical and Clinical GeneticsUniversity of HelsinkiHelsinkiFinland
- Folkhälsan Research CenterHelsinkiFinland
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