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Bianco J, Chu F, Bergsland K, Coe F, Worcester E, Prochaska M. What treatments reduce kidney stone risk in patients with bowel disease? Urolithiasis 2022; 50:557-565. [PMID: 35976425 PMCID: PMC9972896 DOI: 10.1007/s00240-022-01352-z] [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: 11/18/2021] [Accepted: 08/05/2022] [Indexed: 12/30/2022]
Abstract
We examined how physicians made therapeutic choices to decrease stone risk in patients with bowel disease without colon resection, many of whom have enteric hyperoxaluria (EH), at a single clinic. We analyzed clinic records and 24-h urine collections before and after the first clinic visit, among 100 stone formers with bowel disease. We used multivariate linear regression and t tests to compare effects of fluid intake, alkali supplementation, and oxalate-focused interventions on urine characteristics. Patients advised to increase fluid intake had lower initial urine volumes (L/day; 1.3 ± 0.5 vs. 1.7 ± 0.7) and increased volume more than those not so advised (0.7 ± 0.6 vs. 0.3 ± 0.6 p = 0.03; intervention vs. non-intervention). Calcium oxalate supersaturation (CaOx SS) fell (95% CI -4.3 to -0.8). Alkali supplementation increased urine pH (0.34 ± 0.53 vs. 0.22 ± 0.55, p = 0.26) and urine citrate (mg/d; 83 ± 256 vs. 98 ± 166, p = 0.74). Patients advised to reduce oxalate (mg/day) absorption had higher urine oxalate at baseline (88 ± 44 vs. 50 ± 26) which was unchanged on follow-up (88 (baseline) vs. 91 (follow-up), p = 0.90). Neither alkali (95% CI -1.4 to 2.1) nor oxalate-focused advice (95% CI -1.2 to 2.3) lowered CaOx SS. Physicians chose treatments based on baseline urine characteristics. Advice to increase fluid intake increased urine volume and decreased CaOx SS. Alkali and oxalate interventions were ineffective.
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Affiliation(s)
- Julianna Bianco
- Department of Medicine, Nephrology Section/MC 5100, University of Chicago Medicine, 5841 S. Maryland Avenue, Chicago, IL, 60637, USA
| | - Francesca Chu
- Department of Medicine, Nephrology Section/MC 5100, University of Chicago Medicine, 5841 S. Maryland Avenue, Chicago, IL, 60637, USA
| | - Kristin Bergsland
- Department of Medicine, Nephrology Section/MC 5100, University of Chicago Medicine, 5841 S. Maryland Avenue, Chicago, IL, 60637, USA
| | - Fredric Coe
- Department of Medicine, Nephrology Section/MC 5100, University of Chicago Medicine, 5841 S. Maryland Avenue, Chicago, IL, 60637, USA
| | - Elaine Worcester
- Department of Medicine, Nephrology Section/MC 5100, University of Chicago Medicine, 5841 S. Maryland Avenue, Chicago, IL, 60637, USA
| | - Megan Prochaska
- Department of Medicine, Nephrology Section/MC 5100, University of Chicago Medicine, 5841 S. Maryland Avenue, Chicago, IL, 60637, USA.
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Li P, He Q, Jin J, Liu Y, Wen Y, Zhao K, Mao G, Fan W, Yang J. Tomato Oxalyl-CoA Synthetase Degrades Oxalate and Affects Fruit Quality. FRONTIERS IN PLANT SCIENCE 2022; 13:951386. [PMID: 35874016 PMCID: PMC9301600 DOI: 10.3389/fpls.2022.951386] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 06/14/2022] [Indexed: 06/15/2023]
Abstract
Acyl activating enzyme 3 (AAE3) encodes oxalyl-CoA synthetase involved in oxalate degradation. In this study, we investigated the role of AAE3 (SlAAE3) in the fruit quality of tomato (Solanum lycopersicum). The purified recombinant SlAAE3 protein from Escherichia coli exhibited a high activity toward oxalate, with a K m of 223.8 ± 20.03 μm and V max of 7.908 ± 0.606 μmol mg-1 protein min-1. Transient expression of SlAAE3-green fluorescent protein (GFP) fusion proteins suggests that SlAAE3 is a soluble protein without specific subcellular localization. The expression of SlAAE3 is both tissue- and development-dependent, and increased during fruit ripping. The Slaae3 knockout mutants had improved fruit quality as evidenced by the increased sugar-acid ratio and mineral nutrient content. To find the mechanism by which SlAAE3 affects fruit quality, transcriptome, and metabolome were employed on SlAAE3 over-expressed line and wide type fruits. The transcriptomic and metabolic profiles indicated that SlAAE3 in fruits mainly functions at 20 days post-anthesis (20 DPA) and mature green (MG) stages, resulting in up-regulation of amino acid derivatives, nucleotides, and derivatives, but down-regulation of lipid compounds. However, differentially expressed genes (DEGs) were mainly enriched at redox pathways. Taken together, both in vivo and in vitro results suggest that SlAAE3-encoded protein acts as an oxalyl-CoA synthetase, which also participates in redox metabolism. These data provide a further understanding of the mechanism by which SlAAE3 participates in tomato fruit quality.
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Affiliation(s)
- Pengfei Li
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Science, Zhejiang University, Hangzhou, China
| | - Qiyu He
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Science, Zhejiang University, Hangzhou, China
| | - Jianfeng Jin
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Science, Zhejiang University, Hangzhou, China
| | - Yu Liu
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Science, Zhejiang University, Hangzhou, China
| | - Yuxin Wen
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Science, Zhejiang University, Hangzhou, China
| | - Kai Zhao
- College of Horticulture and Landscape, Yunnan Agricultural University, Kunming, China
| | - Guangqun Mao
- College of Horticulture and Landscape, Yunnan Agricultural University, Kunming, China
| | - Wei Fan
- College of Horticulture and Landscape, Yunnan Agricultural University, Kunming, China
| | - Jianli Yang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Science, Zhejiang University, Hangzhou, China
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Whittamore JM, Hatch M. Oxalate Flux Across the Intestine: Contributions from Membrane Transporters. Compr Physiol 2021; 12:2835-2875. [PMID: 34964122 DOI: 10.1002/cphy.c210013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Epithelial oxalate transport is fundamental to the role occupied by the gastrointestinal (GI) tract in oxalate homeostasis. The absorption of dietary oxalate, together with its secretion into the intestine, and degradation by the gut microbiota, can all influence the excretion of this nonfunctional terminal metabolite in the urine. Knowledge of the transport mechanisms is relevant to understanding the pathophysiology of hyperoxaluria, a risk factor in kidney stone formation, for which the intestine also offers a potential means of treatment. The following discussion presents an expansive review of intestinal oxalate transport. We begin with an overview of the fate of oxalate, focusing on the sources, rates, and locations of absorption and secretion along the GI tract. We then consider the mechanisms and pathways of transport across the epithelial barrier, discussing the transcellular, and paracellular components. There is an emphasis on the membrane-bound anion transporters, in particular, those belonging to the large multifunctional Slc26 gene family, many of which are expressed throughout the GI tract, and we summarize what is currently known about their participation in oxalate transport. In the final section, we examine the physiological stimuli proposed to be involved in regulating some of these pathways, encompassing intestinal adaptations in response to chronic kidney disease, metabolic acid-base disorders, obesity, and following gastric bypass surgery. There is also an update on research into the probiotic, Oxalobacter formigenes, and the basis of its unique interaction with the gut epithelium. © 2021 American Physiological Society. Compr Physiol 11:1-41, 2021.
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Affiliation(s)
- Jonathan M Whittamore
- Department of Pathology, Immunology and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Marguerite Hatch
- Department of Pathology, Immunology and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, Florida, USA
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Kumar V, Irfan M, Datta A. Manipulation of oxalate metabolism in plants for improving food quality and productivity. PHYTOCHEMISTRY 2019; 158:103-109. [PMID: 30500595 DOI: 10.1016/j.phytochem.2018.10.029] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 10/23/2018] [Accepted: 10/26/2018] [Indexed: 05/25/2023]
Abstract
Oxalic acid is a naturally occurring metabolite in plants and a common constituent of all plant-derived human diets. Oxalic acid has diverse unrelated roles in plant metabolism, including pH regulation in association with nitrogen metabolism, metal ion homeostasis and calcium storage. In plants, oxalic acid is also a pathogenesis factor and is secreted by various fungi during host infection. Unlike those of plants, fungi and bacteria, the human genome does not contain any oxalate-degrading genes, and therefore, the consumption of large amounts of plant-derived oxalate is considered detrimental to human health. In this review, we discuss recent biotechnological approaches that have been used to reduce the oxalate content of plant tissues.
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Affiliation(s)
- Vinay Kumar
- National Institute of Plant Genome Research, New Delhi, 110067, India
| | - Mohammad Irfan
- National Institute of Plant Genome Research, New Delhi, 110067, India
| | - Asis Datta
- National Institute of Plant Genome Research, New Delhi, 110067, India.
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Peck AB, Canales BK, Nguyen CQ. Oxalate-degrading microorganisms or oxalate-degrading enzymes: which is the future therapy for enzymatic dissolution of calcium-oxalate uroliths in recurrent stone disease? Urolithiasis 2015; 44:45-50. [PMID: 26645869 DOI: 10.1007/s00240-015-0845-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 11/05/2015] [Indexed: 12/25/2022]
Abstract
Renal urolithiasis is a pathological condition common to a multitude of genetic, physiological and nutritional disorders, ranging from general hyperoxaluria to obesity. The concept of quickly dissolving renal uroliths via chemolysis, especially calcium-oxalate kidney stones, has long been a clinical goal, but yet to be achieved. Over the past 25 years, there has been a serious effort to examine the prospects of using plant and microbial oxalate-degrading enzymes known to catabolize oxalic acid and oxalate salts. While evidence is emerging that bacterial probiotics can reduce recurrent calcium-oxalate kidney stone disease by lowering systemic hyperoxaluria, the possible use of free oxalate-degrading enzyme therapy remains a challenge with several hurdles to overcome before reaching clinical practice.
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Affiliation(s)
- Ammon B Peck
- Department of Infectious Diseases and Pathology, University of Florida College of Veterinary Medicine, P.O Box 100125, VAB, Bldg 1017, Gainesville, FL, 32610, USA.
| | - Benjamin K Canales
- Department of Urology, University of Florida College of Medicine, P.O. Box 100247, 1600 SW Archer Rd, Gainesville, FL, 32610, USA
| | - Cuong Q Nguyen
- Department of Infectious Diseases and Pathology, University of Florida College of Veterinary Medicine, P.O Box 100125, VAB, Bldg 1017, Gainesville, FL, 32610, USA
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NADPH oxidase as a therapeutic target for oxalate induced injury in kidneys. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2013; 2013:462361. [PMID: 23840917 PMCID: PMC3690252 DOI: 10.1155/2013/462361] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2013] [Accepted: 05/14/2013] [Indexed: 02/07/2023]
Abstract
A major role of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase family of enzymes is to catalyze the production of superoxides and other reactive oxygen species (ROS). These ROS, in turn, play a key role as messengers in cell signal transduction and cell cycling, but when they are produced in excess they can lead to oxidative stress (OS). Oxidative stress in the kidneys is now considered a major cause of renal injury and inflammation, giving rise to a variety of pathological disorders. In this review, we discuss the putative role of oxalate in producing oxidative stress via the production of reactive oxygen species by isoforms of NADPH oxidases expressed in different cellular locations of the kidneys. Most renal cells produce ROS, and recent data indicate a direct correlation between upregulated gene expressions of NADPH oxidase, ROS, and inflammation. Renal tissue expression of multiple NADPH oxidase isoforms most likely will impact the future use of different antioxidants and NADPH oxidase inhibitors to minimize OS and renal tissue injury in hyperoxaluria-induced kidney stone disease.
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Apocynin-treatment reverses hyperoxaluria induced changes in NADPH oxidase system expression in rat kidneys: a transcriptional study. PLoS One 2012; 7:e47738. [PMID: 23091645 PMCID: PMC3473023 DOI: 10.1371/journal.pone.0047738] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 09/14/2012] [Indexed: 11/25/2022] Open
Abstract
Purpose We have previously shown that production of reactive oxygen species (ROS) is an important contributor to renal injury and inflammation following exposure to oxalate (Ox) or calcium-oxalate (CaOx) crystals. The present study was conducted, utilizing global transcriptome analyses, to determine the effect of Apocynin on changes in the NADPH oxidase system activated in kidneys of rats fed a diet leading to hyperoxaluria and CaOx crystal deposition. Approach Age-, sex- and weight-matched rats were either fed regular rat chow or regular rat chow supplemented with 5% w/w hydroxy-L-proline (HLP). Half of the rats on the HLP diet were also placed on Apocynin-supplemented H2O. After 28 days, each rat was euthanized, their kidneys freshly explanted and dissected to obtain both cortex and medulla tissues. Total RNA was extracted from each tissue and subjected to genomic microarrays to obtain global transcriptome data. KEGG was used to identify gene clusters with differentially expressed genes. Immunohistochemistry was used to confirm protein expressions of selected genes. Results Genes encoding both membrane- and cytosolic-NADPH oxidase complex-associated proteins, together with p21rac and Rap1a, were coordinately up-regulated significantly in both renal medulla and cortex tissues in the HLP-fed rats compared to normal healthy untreated controls. Activation of NADPH oxidase appears to occur via the angiotensin-II/angiotensin-II receptor-2 pathway, although the DAG-PKC pathway of neutrophils may also contribute. Immuno histochemical staining confirmed up-regulated gene expressions. Simultaneously, genes encoding ROS scavenger proteins were down-regulated. HLP-fed rats receiving Apocynin had a complete reversal in the differential-expression of the NADPH oxidase system genes, despite showing similar levels of hyperoxaluria. Conclusions A strong up-regulation of an oxidative/respiratory burst involving the NADPH oxidase system, activated via the angiotensin-II and most likely the DAG-PKC pathways, occurs in kidneys of hyperoxaluric rats. Apocynin treatment reversed this activation without affecting the levels of hyperoxaluria.
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Sakhaee K, Maalouf NM, Sinnott B. Clinical review. Kidney stones 2012: pathogenesis, diagnosis, and management. J Clin Endocrinol Metab 2012; 97:1847-60. [PMID: 22466339 PMCID: PMC3387413 DOI: 10.1210/jc.2011-3492] [Citation(s) in RCA: 145] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
CONTEXT The pathogenetic mechanisms of kidney stone formation are complex and involve both metabolic and environmental risk factors. Over the past decade, major advances have been made in the understanding of the pathogenesis, diagnosis, and treatment of kidney stone disease. EVIDENCE ACQUISITION AND SYNTHESIS Both original and review articles were found via PubMed search reporting on pathophysiology, diagnosis, and management of kidney stones. These resources were integrated with the authors' knowledge of the field. CONCLUSION Nephrolithiasis remains a major economic and health burden worldwide. Nephrolithiasis is considered a systemic disorder associated with chronic kidney disease, bone loss and fractures, increased risk of coronary artery disease, hypertension, type 2 diabetes mellitus, and the metabolic syndrome. Further understanding of the pathophysiological link between nephrolithiasis and these systemic disorders is necessary for the development of new therapeutic options.
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Affiliation(s)
- Khashayar Sakhaee
- Department of Internal Medicine, Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA.
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9
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Oxalate and Urolithiasis. Urolithiasis 2012. [DOI: 10.1007/978-1-4471-4387-1_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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10
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Abstract
Hyperoxaluria leads to urinary calcium oxalate (CaOx) supersaturation, resulting in the formation and retention of CaOx crystals in renal tissue. CaOx crystals may contribute to the formation of diffuse renal calcifications (nephrocalcinosis) or stones (nephrolithiasis). When the innate renal defense mechanisms are suppressed, injury and progressive inflammation caused by these CaOx crystals, together with secondary complications such as tubular obstruction, may lead to decreased renal function and in severe cases to end-stage renal failure. For decades, research on nephrocalcinosis and nephrolithiasis mainly focused on both the physicochemistry of crystal formation and the cell biology of crystal retention. Although both have been characterized quite well, the mechanisms involved in establishing urinary supersaturation in vivo are insufficiently understood, particularly with respect to oxalate. Therefore, current therapeutic strategies often fail in their compliance or effectiveness, and CaOx stone recurrence is still common. As the etiology of hyperoxaluria is diverse, a good understanding of how oxalate is absorbed and transported throughout the body, together with a better insight in the regulatory mechanisms, is crucial in the setting of future treatment strategies of this disorder. In this review, the currently known mechanisms of oxalate handling in relevant organs will be discussed in relation to the different etiologies of hyperoxaluria. Furthermore, future directions in the treatment of hyperoxaluria will be covered.
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11
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Diet, but not oral probiotics, effectively reduces urinary oxalate excretion and calcium oxalate supersaturation. Kidney Int 2010; 78:1178-85. [PMID: 20736987 DOI: 10.1038/ki.2010.310] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
We examined the effect of a controlled diet and two probiotic preparations on urinary oxalate excretion, a risk factor for calcium oxalate kidney stone formation, in patients with mild hyperoxaluria. Patients were randomized to a placebo, a probiotic, or a synbiotic preparation. This tested whether these probiotic preparations can increase oxalate metabolism in the intestine and/or decrease oxalate absorption from the gut. Patients were maintained on a controlled diet to remove the confounding variable of differing oxalate intake from food. Urinary oxalate excretion and calcium oxalate supersaturation on the controlled diet were significantly lower compared with baseline on a free-choice diet. Neither study preparation reduced urinary oxalate excretion nor calcium oxalate supersaturation. Fecal lactobacilli colony counts increased on both preparations, whereas enterococcal and yeast colony counts were increased on the synbiotic. Total urine volume and the excretion of oxalate and calcium were all strong independent determinants of urinary calcium oxalate supersaturation. Hence, dietary oxalate restriction reduced urinary oxalate excretion, but the tested probiotics did not influence urinary oxalate levels in patients on a restricted oxalate diet. However, this study suggests that dietary oxalate restriction is useful for kidney stone prevention.
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Abstract
Over the past 10 years, major progress has been made in the pathogenesis of uric acid and calcium stones. These advances have led to our further understanding of a pathogenetic link between uric acid nephrolithiasis and the metabolic syndrome, the role of Oxalobacter formigenes in calcium oxalate stone formation, oxalate transport in Slc26a6-null mice, the potential pathogenetic role of Randall's plaque as a precursor for calcium oxalate nephrolithiasis, and the role of renal tubular crystal retention. With these advances, we may target the development of novel drugs including (1) insulin sensitizers; (2) probiotic therapy with O. formigenes, recombinant enzymes, or engineered bacteria; (3) treatments that involve the upregulation of intestinal luminal oxalate secretion by increasing anion transporter activity (Slc26a6), luminally active nonabsorbed agents, or oxalate binders; and (4) drugs that prevent the formation of Randall's plaque and/or renal tubular crystal adhesions.
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Affiliation(s)
- Khashayar Sakhaee
- Department of Internal Medicine, Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390-8885, USA.
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13
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Sikora P, von Unruh GE, Beck B, Feldkötter M, Zajaczkowska M, Hesse A, Hoppe B. [13C2]oxalate absorption in children with idiopathic calcium oxalate urolithiasis or primary hyperoxaluria. Kidney Int 2008; 73:1181-6. [PMID: 18337715 DOI: 10.1038/ki.2008.63] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Intestinal oxalate absorption is an important part of oxalate metabolism influencing its urinary excretion and its measurement can be a valuable diagnostic tool in hyperoxaluric disorders. In this study, we use [(13)C(2)]oxalate absorption under standardized dietary conditions to assess intestinal oxalate absorption and its impact on urinary oxalate excretion. Tests were conducted in age-matched pediatric patients that included 60 with idiopathic calcium oxalate urolithiasis, 13 with primary hyperoxaluria, and 35 healthy children. In the idiopathic stone formers, median oxalate absorption was significantly higher than that in the controls or in patients with primary disease. From standardized values obtained in control patients, oxalate hyperabsorption was detected in 23 patients with idiopathic disease but not in any patients with primary hyperoxaluria; therefore, a significant correlation between intestinal absorption and urinary excretion was found only in those with the idiopathic disease. We have shown that increased intestinal oxalate absorption is an important risk factor of idiopathic calcium oxalate urolithiasis. In contrast, low intestinal oxalate absorption in patients with primary hyperoxaluria indicates that only foods with excessive oxalate content be restricted from their diet.
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Affiliation(s)
- P Sikora
- Department of Pediatric Nephrology, Lublin Medical University, Lublin, Poland
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Voss S, Hesse A, Zimmermann DJ, Sauerbruch T, von Unruh GE. Intestinal Oxalate Absorption is Higher in Idiopathic Calcium Oxalate Stone Formers Than in Healthy Controls: Measurements With the [13C2]Oxalate Absorption Test. J Urol 2006; 175:1711-5. [PMID: 16600737 DOI: 10.1016/s0022-5347(05)01001-3] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2005] [Indexed: 10/24/2022]
Abstract
PURPOSE We assessed the importance of oxalate hyperabsorption for idiopathic calcium oxalate urolithiasis, oxalate absorption in healthy volunteers and recurrent calcium oxalate stone formers was compared. MATERIALS AND METHODS The [(13)C2]oxalate absorption test, a standardized, radioactivity-free test, was performed. On 2 days 24-hour urine was collected and an identical standard diet containing 800 mg Ca daily was maintained. On the morning of day 2 a capsule containing 0.37 mmol sodium [(13)C2]oxalate was ingested. A total of 120 healthy volunteers (60 women and 60 men) and 120 patients (30 women and 90 men) with idiopathic CaOx urolithiasis (60% or greater CaOx) were tested. RESULTS Mean intestinal oxalate absorption in the volunteers was 8.0 +/- 4.4%, and in the patients was 10.2 +/- 5.2% (p <0.001). There was no significant difference in mean absorption values between men and women within both groups. A high overlap between the absorption values of volunteers and patients was found. Only in the patient group did absorption values greater than 20% occur. Oxalate absorption correlated with oxalate excretion in the patients, r = 0.529 (p <0.01) and in the volunteers, r = 0.307 (p <0.01). CONCLUSIONS In high oxalate absorbers dietary oxalate has a significant role in oxalate excretion and, therefore, increases the risk of calcium oxalate stone formation.
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Affiliation(s)
- Susanne Voss
- Department of Urology (Division of Experimental Urology), University of Bonn, Bonn, Germany
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15
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Abstract
BACKGROUND Patients with inflammatory bowel disease have a 10- to 100-fold increased risk of nephrolithiasis, with enteric hyperoxaluria being the major risk factor for these and other patients with fat malabsorptive states. Endogenous components of the intestinal microflora can potentially limit dietary oxalate absorption. METHODS Ten patients were studied with chronic fat malabsorption, calcium oxalate stones, and hyperoxaluria thought to be caused by jejunoileal bypass (1) and Roux-en-Y gastric bypass surgery for obesity (4), dumping syndrome secondary to gastrectomy (2), celiac sprue (1), chronic pancreatitis (1), and ulcerative colitis in remission (1). For 3 months, patients received increasing doses of a lactic acid bacteria mixture (Oxadrop), VSL Pharmaceuticals), followed by a washout month. Twenty-four-hour urine collections were performed at baseline and after each month. RESULTS Mean urinary oxalate excretion fell by 19% after 1 month (1 dose per day, P < 0.05), and oxalate excretion remained reduced by 24% during the second month (2 doses per day, P < 0.05). During the third month on 3 doses per day oxalate excretion increased slightly, so that the mean was close to the baseline established off treatment. Urinary oxalate again fell 20% from baseline during the washout period. Calcium oxalate supersaturation was reduced while on Oxadrop, largely due to the decrease in oxalate excretion, although mean changes did not reach statistical significance. CONCLUSION Manipulation of gastrointestinal (GI) flora can influence urinary oxalate excretion to reduce urinary supersaturation levels. These changes could have a salutary effect on stone formation rates. Further studies will be needed to establish the optimal dosing regimen.
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Affiliation(s)
- John C Lieske
- Division of Nephrology and Hypertension, Mayo Clinic, Mayo Hyperoxaluria Center, and Mayo Complementary and Integrative Medicine Program, Rochester, Minnesota 55905, USA.
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16
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Chai W, Liebman M, Kynast-Gales S, Massey L. Oxalate absorption and endogenous oxalate synthesis from ascorbate in calcium oxalate stone formers and non-stone formers. Am J Kidney Dis 2005; 44:1060-9. [PMID: 15558527 DOI: 10.1053/j.ajkd.2004.08.028] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Increased rates of either oxalate absorption or endogenous oxalate synthesis can contribute to hyperoxaluria, a primary risk factor for the formation of calcium oxalate-containing kidney stones. This study involves a comparative assessment of oxalate absorption and endogenous oxalate synthesis in subpopulations of stone formers (SFs) and non-stone formers (NSFs) and an assessment of the effect of ascorbate supplementation on oxalate absorption and endogenous oxalate synthesis. METHODS Twenty-nine individuals with a history of calcium oxalate kidney stones (19 men, 10 women) and 19 age-matched NSFs (8 men, 11 women) participated in two 6-day controlled feeding experimental periods: ascorbate-supplement (2 g/d) and no-supplement treatments. An oxalate load consisting of 118 mg of unlabeled oxalate and 18 mg of 13C2 -oxalic acid was administered the morning of day 6 of each experimental period. RESULTS Mean 13C2 -oxalic acid absorption averaged across the ascorbate and no-supplement treatments was significantly greater in SFs (9.9%) than NSFs (8.0%). SFs also had significantly greater 24-hour post-oxalate load urinary total oxalate and endogenous oxalate levels with both treatments. Twenty-four-hour urinary total oxalate level correlated strongly with both 13C2 -oxalic acid absorption (SFs, r = 0.76; P < 0.01; NSFs, r = 0.62; P < 0.01) and endogenous oxalate synthesis (SFs, r = 0.95; P < 0.01; NSFs, r = 0.92; P < 0.01). CONCLUSION SFs are characterized by greater rates of both oxalate absorption and endogenous oxalate synthesis, and both these factors contribute to the hyperoxaluric state. The finding that ascorbate supplementation increased urinary total and endogenous oxalate levels suggested that this practice is a risk factor for individuals predisposed to kidney stones.
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Affiliation(s)
- Weiwen Chai
- Department of Family and Consumer Sciences (Nutrition), University of Wyoming, Laramie, WY 82071, USA
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17
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Hatch M, Freel RW. Intestinal transport of an obdurate anion: oxalate. ACTA ACUST UNITED AC 2004; 33:1-16. [PMID: 15565438 DOI: 10.1007/s00240-004-0445-3] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2004] [Accepted: 07/19/2004] [Indexed: 12/15/2022]
Abstract
In this review, we focus on the role of gastrointestinal transport of oxalate primarily from a contemporary physiological standpoint with an emphasis on those aspects that we believe may be most important in efforts to mitigate the untoward effects of oxalate. Included in this review is a general discussion of intestinal solute transport as it relates to oxalate, considering cellular and paracellular avenues, the transport mechanisms, and the molecular identities of oxalate transporters. In addition, we review the role of the intestine in oxalate disease states and various factors affecting oxalate absorption.
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Affiliation(s)
- Marguerite Hatch
- Department of Pathology, Immunology and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, P.O. Box 100275, 1600 S.W. Archer Road, FL 32610, USA.
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Krishnamurthy MS, Hruska KA, Chandhoke PS. The urinary response to an oral oxalate load in recurrent calcium stone formers. J Urol 2003; 169:2030-3. [PMID: 12771711 DOI: 10.1097/01.ju.0000062527.37579.49] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE Dietary oxalate may contribute up to 50% to 80% of the oxalate excreted in urine. We studied the urinary response to an oral oxalate load in male and female idiopathic recurrent calcium oxalate stone formers with and without mild hyperoxaluria to evaluate the potential pathophysiological significance of dietary oxalate. MATERIALS AND METHODS A total of 60 recurrent calcium stone formers underwent an oral oxalate load test. Urine samples were obtained after an overnight fast. Each patient then received an oral oxalate load (5 mM. sodium oxalate dissolved in 250 ml. distilled water) and 3, 2-hour urine samples were obtained 2, 4 and 6 hours after the oxalate load. We compared the response to the oxalate load in patients with and without mild hyperoxaluria, and in male and female patients without hyperoxaluria. RESULTS The peak urinary response occurred 4 hours after the oral oxalate load in all patients. Those with mild hyperoxaluria had a mean fasting urinary oxalate-to-creatinine ratio +/- SE of 0.027 +/- 0.003 and a mean peak urinary oxalate-to-creatinine ratio of 0.071 +/- 0.006. In comparison, patients with normal oxalate excretion had a fasting and peak urinary oxalate-to-creatinine ratio of 0.018 +/- 0.001 and 0.056 +/- 0.004, respectively (p <0.05). The mean 6-hour increment for urinary oxalate excretion after the oxalate load for patients with hyperoxaluria versus those with normal urinary oxalate excretion was 17.2 +/- 1.9 versus 12.1 +/- 0.98 mg. (p <0.05). In the subset of patients with normal urinary oxalate excretion mean 6-hour cumulative urinary oxalate excretion was 16.8 +/- 1.3 and 13.3 +/- 1.4 mg. in males and females, respectively (p not significant). CONCLUSIONS Recurrent calcium stone formers with mild hyperoxaluria have higher fasting urinary oxalate and an exaggerated urinary response to an oral oxalate load compared with recurrent calcium stone formers with normal urinary oxalate excretion. Men and women stone formers without hyperoxaluria excrete similar fractions of an oral oxalate load. Increased gastrointestinal absorption and renal excretion of dietary oxalate may be a significant pathophysiological mechanism of stone formation in patients with mild hyperoxaluria.
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Affiliation(s)
- Mina S Krishnamurthy
- Department of Surgery (Urology), University of Colorado Health Sciences Center, Denver, Colorado, USA
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von UNRUH GERDE, VOSS SUSANNE, SAUERBRUCH TILMAN, HESSE ALBRECHT. Reference Range for Gastrointestinal Oxalate Absorption Measured With a Standardized [13C2]Oxalate Absorption Test. J Urol 2003. [DOI: 10.1016/s0022-5347(05)63993-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- GERD E. von UNRUH
- From the Departments of Internal Medicine I and Urology (Division of Experimental Urology), University of Bonn, Bonn, Germany
| | - SUSANNE VOSS
- From the Departments of Internal Medicine I and Urology (Division of Experimental Urology), University of Bonn, Bonn, Germany
| | - TILMAN SAUERBRUCH
- From the Departments of Internal Medicine I and Urology (Division of Experimental Urology), University of Bonn, Bonn, Germany
| | - ALBRECHT HESSE
- From the Departments of Internal Medicine I and Urology (Division of Experimental Urology), University of Bonn, Bonn, Germany
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20
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Abstract
Hyperoxaluria leads to increased calcium oxalate supersaturation and calcium oxalate stone formation. Excess oxalate can arise from endogenous overproduction as in primary hyperoxaluria or from dietary sources. In the last 15 years great strides have been made in the diagnosis and treatment of primary hyperoxaluria. However options still seem limited in treating the mild hyperoxaluria found in many stone formers. Inadequate knowledge of food oxalate content, the effect of dietary oxalate precursors on oxalate excretion, and the factors affecting handling of oxalate by the intestine prevent development of rational therapies for treatment of hyperoxaluria. Recent studies of oxalate degrading bacteria and renewed interest in the role of diet calcium in oxalate absorption may lead to better therapeutic strategies for hyperoxaluric calcium nephrolithiasis.
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Affiliation(s)
- John R Asplin
- University of Chicago and Litholink Corporation, 2250 W. Campbell Park Drive, Chicago, IL 60612, USA.
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21
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Abstract
Kidney stones are increased in patients with bowel disease, particularly those who have had resection of part of their gastrointestinal tract. These stones are usually CaOx, but there is a marked increase in the tendency to form uric acid stones, as well, particularly in patients with colon resection. These patients all share a tendency to chronic volume contraction due to loss of water and salt in diarrheal stool, which leads to decreased urine volumes. They also have decreased absorption, and therefore diminished urinary excretion, of citrate and magnesium, which normally act as inhibitors of CaOx crystallization. Patients with colon resection and ileostomy form uric acid stones, as loss of bicarbonate in the ileostomy effluent leads to formation of an acid urine. This, coupled with low urine volume, decreases the solubility of uric acid, causing crystallization and stone formation. Prevention of stones requires treatment with alkalinizing agents to raise urine pH to about 6.5, and attempts to increase urine volume, which increases the solubility of uric acid and prevents crystallization. Patients with small bowel resection may develop steatorrhea; if the colon is present, they are at risk of hyperoxaluria due to increased permeability of the colon to oxalate in the presence of fatty acids, and increased concentrations of free oxalate in the bowel lumen due to fatty acid binding of luminal calcium. EH leads to supersaturation of urine with respect to CaOx, in conjunction with low volume, hypocitraturia and hypomagnesuria. Therapy involves a low-fat, low-oxalate diet, attempts to increase urine volume, and agents such as calcium given to bind oxalate in the gut lumen. Correction of hypocitraturia and hypomagnesuria are also helpful.
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Affiliation(s)
- Elaine M Worcester
- Lake Park Dialysis Unit, Division of Nephrology, Department of Clinical Medicine, University of Chicago, 1531 East Hyde Park Boulevard, Chicago, IL 60615, USA.
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23
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Masai M, Ito H, Kotake T. Effect of dietary intake on urinary oxalate excretion in calcium renal stone formers. BRITISH JOURNAL OF UROLOGY 1995; 76:692-6. [PMID: 8535710 DOI: 10.1111/j.1464-410x.1995.tb00758.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE To investigate the influence of dietary intake on urinary oxalate excretion in calcium renal-stone formers. PATIENTS AND METHODS Dietary intake was monitored by using the dietary-record method in 60 idiopathic stone formers. The patients collected their urine for 24 h at home and their urinary oxalate excretion rate was determined. The relationship between the daily intake of various nutrients and urinary oxalate excretion was examined by both monovariate and multivariate analyses. RESULTS By monovariate analysis, the intake of carbohydrate, total protein and fat were significantly correlated with urinary oxalate excretion, but the intake of calcium and body surface area were not. In addition, the intake of total protein was highly correlated with that of fat. By multivariate analysis, the intake of carbohydrate and fat were significantly related to urinary oxalate excretion, and the intake of calcium was inversely correlated with urinary oxalate excretion, but the intake of total protein showed no significant correlation. CONCLUSION The intake of carbohydrate and fat was positively and the intake of calcium was inversely correlated with urinary oxalate excretion in stone formers and, taken together, these findings suggested that fat plays an important role in urinary oxalate excretion and that protein has a minimal effect.
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Affiliation(s)
- M Masai
- Department of Urology, Teikyo University School of Medicine, Ichihara Hospital, Japan
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Reusz GS, Dobos M, Byrd D, Sallay P, Miltényi M, Tulassay T. Urinary calcium and oxalate excretion in children. Pediatr Nephrol 1995; 9:39-44. [PMID: 7742220 DOI: 10.1007/bf00858966] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We have established normal values for calcium/creatinine (Ca/Cr) and oxalate/creatinine (Ox/Cr) ratios in 25 infants (aged 1-7 days) and 391 children (aged 1 month to 14.5 years) and compared these with values obtained in 137 children with post-glomerular haematuria and 27 with nephrolithiasis. Oxalate was measured by ion chromatography. Nomograms of Marshall and Robertson were used to calculate urine saturation to calcium oxalate. The Ca/Cr ratio was normally distributed whereas the Ox/Cr ratio had a log-normal distribution. The molar ratio of Ca/Cr was the lowest in the first days of life and the highest between 7 month and 1.5 years (mean +/- SD = 0.39 +/- 0.28 mmol/mmol). Following a slight decrease it stabilised by the age of 6 years (0.34 +/- 0.19 mmol/mmol). The highest Ox/Cr values were measured during the 1st month of life [geometric mean 133 (range 61-280) mumol/mmol], followed by a gradual decrease until 11 years of age [mean 24 (range 6-82) mumol/mmol]. Thirty-six haematuric children had hypercalciuria (26%), 23 had absorptive hypercalciuria, 13 renal type. Children with absorptive hypercalciuria on a calcium-restricted diet had significantly higher oxalate excretion than those with renal hypercalciuria and the control group [38 (range 28-49) vs. 22 (range 16-29) and 23 (range 22-27) mumol/mol respectively, P < 0.01]. Calcium oxalate urine saturation of stone patients was higher than that of patients with haematuria and the normal population (1.18 +/- 0.05 vs. 1.06 +/- 0.03, P < 0.03 and 0.84 +/- 0.03, P < 0.001 respectively).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- G S Reusz
- First Department of Paediatrics, Semmelweis University Medical School, Budapest, Hungary
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Abstract
New information is provided regarding the site and nature of intestinal oxalate absorption in man. Intestinal absorption of oxalate was assessed indirectly from the increase in renal oxalate excretion following gastric administration of 5 mmol. oxalate loads. Four different types of loads have been used: sodium oxalate, sodium oxalate plus calcium gluconate, rhubarb and spinach. Studies were performed in 6 adult patients on permanent gastric tube feeding for various reasons. Gastric emptying was blocked by an intrapyloric balloon for the duration of the experiments and the gastric oxalate load was evacuated before the balloon was deflated. Under these conditions calcium oxalate was absorbed to the same extent as soluble oxalate. With increasing gastric loading time there is a linear increase in the urinary oxalate excretion: 15 to 21% of the gastric oxalate load appeared in the urine after 2 hours of loading, 24 to 45% after 4 hours and as much as 62% after 6 hours. These absorption kinetics and our experiment suggest that the stomach is not only just another oxalate absorption site but seems to be the critical site for intestinal oxalate absorption in an intact gastrointestinal tract. This finding opens a new field for the discussion of etiology and pathogenesis of calcium oxalate stone formation.
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Affiliation(s)
- R E Hautmann
- Department of Urology, Faculty of Medicine, University of Ulm, Germany
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26
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Lindsjö M, Danielson BG, Fellström B, Norheim I, Wide L, Ljunghall S. Parathyroid function in relation to intestinal function and renal calcium reabsorption in patients with nephrolithiasis. SCANDINAVIAN JOURNAL OF UROLOGY AND NEPHROLOGY 1992; 26:55-64. [PMID: 1631508 DOI: 10.3109/00365599209180397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Recently a technique to measure intact parathyroid hormone (PTH), i.e. the biologically active hormone, has been available. The aim of the present study was to apply this method to evaluate the parathyroid function in a material of recurrent renal stone formers (n = 324). Intact PTH was found to be inversely related to both urinary calcium (r = -0.15; p less than 0.01) and serum calcium (p less than 0.02) indicating that in the majority of the patients with hypercalciuria this was accounted for by intestinal hyperabsorption and not by high serum PTH. Hyperabsorption was also the likely explanation for the finding of a positive relationship between the urinary calcium and oxalate excretions (r = 0.22; p less than 0.001) in medication-free patients without intestinal disorders, i.e. without enteric hyperoxaluria. Altogether 25 patients (7%) had elevated serum PTH concentrations. They were followed up with fasting serum and urinary electrolytes and an oral calcium loading test (1 g of calcium) in order to evaluate the importance of renal and intestinal factors responsible for the elevated serum PTH concentrations. The investigation was carried out on a free diet and on low and high calcium intakes, respectively. The incidence of intestinal malfunction, which was sometimes present without clinical symptoms, was found to be approximately the same as that of impaired renal conservation of calcium. The findings in the patients with intestinal malfunction were a reduced intestinal absorption of calcium and an enhanced tubular reabsorption of calcium (TRCa), with greater reabsorption of calcium for higher PTH values. In patients with impaired renal conservation of calcium despite the raised PTH there was no correlation between PTH and TRCa. When PTH was suppressed during the oral calcium load the TRCa was found to be inappropriately low and the renal defect obvious. The intestinal calcium absorption was secondarily increased to compensate for the renal losses.
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Affiliation(s)
- M Lindsjö
- Department of Internal Medicine, University Hospital, Uppsala, Sweden
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Lindsjö M, Fellström B, Danielson BG, Kasidas GP, Rose GA, Ljunghall S. Hyperoxaluria or hypercalciuria in nephrolithiasis: the importance of renal tubular functions. Eur J Clin Invest 1990; 20:546-54. [PMID: 2124987 DOI: 10.1111/j.1365-2362.1990.tb01900.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The role of the kidney in states of hyperoxaluria and hypercalciuria was investigated in seven patients with hyperoxaluria after jejunoileal bypass (JIB) and six patients with idiopathic hypercalciuria (IHC). Eight apparently healthy persons formed a control group. Besides hyperoxaluria, the patients with JIB displayed an elevated plasma concentration of oxalate and the oxalate clearance was increased and higher than creatinine clearance, indicating a net tubular secretion of oxalate. The JIB patients had lower 24-h urinary excretions of calcium, phosphate, magnesium and citrate and higher serum parathyroid hormone (PTH) than controls, indicating increased secretion of PTH to compensate for calcium malabsorption. IHC patients exhibited increased fasting urinary calcium even though their serum values were similar to those in the controls. These results indicate a reduced tubular calcium reabsorption, which was most pronounced in patients with highest PTH values. We conclude that hyperoxaluria in JIB patients is associated both with intestinal hyperabsorption and with enhanced tubular secretion of oxalate, and that in some patients with IHC hypercalciuria is due to reduced tubular reabsorption of calcium.
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Affiliation(s)
- M Lindsjö
- Department of Internal Medicine, University Hospital, Uppsala, Sweden
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28
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Lindsjö M, Danielson BG, Fellström B, Lithell H, Ljunghall S. Intestinal absorption of oxalate and calcium in patients with jejunoileal bypass. SCANDINAVIAN JOURNAL OF UROLOGY AND NEPHROLOGY 1989; 23:283-9. [PMID: 2595324 DOI: 10.3109/00365598909180339] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Jejunoileal bypass (JIB) has been widely performed for treatment of excessive obesity. Formation of calcium oxalate stones is a common side effect. Since, under physiological conditions, the intestinal absorption of calcium and that of oxalate are interrelated, intestinal oxalate and calcium absorption were measured in the present study by isotope techniques in 19 JIB patients and 20 healthy controls. The JIB patients showed pronounced hyperoxaluria and markedly increased absorption of oxalate, with a urinary excretion of 14C-oxalate of 29 +/- 19% (controls 6.2 +/- 3.7%; p less than 0.001). There was a strong correlation between the intestinal absorption and urinary excretion of oxalate in the JIB patients (r = 0.72; p less than 0.001). Furthermore, their oxalate kinetics was altered, with continued urinary excretion of 14C-oxalate for up to 48 hours. The JIB patients also had reduced calcium absorption (36 +/- 9.1% vs. 47 +/- 9.0%; p less than 0.001) and patients with malabsorption of calcium and low urinary calcium had the highest intestinal absorption and urinary excretion of oxalate. It is concluded that hyperoxaluria in JIB patients is due to a significant extent to hyperabsorption of oxalate.
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Affiliation(s)
- M Lindsjö
- Department of Internal Medicine, University Hospital, Uppsala, Sweden
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