oxalates and Obesity

Hyperoxaluria can cause kidney disease through multiple mechanisms, including tubular obstruction from calcium oxalate crystals, sterile inflammation, and tubular epithelial cell injury. Hyperoxaluria is also observed in individuals with diabetes mellitus and obesity, which are in turn risk factors for chronic kidney disease (CKD). Whether hyperoxaluria is a potential mediator of increased risk of CKD in diabetes mellitus and obesity is unknown.. Individuals with diabetes have increased levels of plasma glyoxal (a protein glycation product) and glyoxylate, both of which are precursors for oxalate. Increased gut absorption of oxalate in obesity may be because of obesity-associated inflammation. A recent study in individuals with CKD found that higher 24 h urinary oxalate excretion was independently associated with increased risk of kidney disease progression, especially in individuals with diabetes and obesity.. Both diabetes mellitus and obesity are associated with higher urinary oxalate excretion through distinct mechanisms. Hyperoxaluria could be a mechanism by which kidney disease develops in individuals with diabetes mellitus or obesity and could also contribute to progressive loss of renal function. Future research on pharmacologic or dietary measures to limit oxalate absorption or generation are required to test whether lowering urinary oxalate excretion is beneficial in preventing kidney disease development and progression in diabetes mellitus and obesity.

Topics: Diabetic Nephropathies; Humans; Hyperoxaluria; Inflammation; Obesity; Oxalates; Renal Insufficiency, Chronic

Urolithiasis is a condition that can cause significant morbidity among patients. Dietary manipulations traditionally advised include fluid, protein, oxalate, calcium, citrate, and sodium changes in the diet. Evidence-based practice guidelines suggest that there is not ample evidence to confidently recommend dietary changes, since inadequate studies have been done to quantify the risks of diet in stone formation. While fluid intake patterns have the weightiest evidence in the literature, not even fluid intake meets the guidelines for evidence-based practice. Health care providers should recognize that current patient education is largely based on intuition. It behooves us as clinicians to look critically at all our practices, review the available literature, and question what we believe we know. A summary of available literature is provided to guide the clinician in educating patients in reducing their risk of recurrent calcium oxalate stone disease.

Topics: Ascorbic Acid; Calcium Oxalate; Calcium, Dietary; Citrates; Dehydration; Diet, Protein-Restricted; Diet, Sodium-Restricted; Evidence-Based Medicine; Feeding Behavior; Fluid Therapy; Humans; Information Services; Internet; Kidney Calculi; Nurse's Role; Nutritional Sciences; Obesity; Oxalates; Patient Education as Topic; Phytotherapy; Practice Guidelines as Topic; Recurrence; Risk Factors

Topics: Adult; Arthritis; Cholestasis; Fatty Liver; Female; Humans; Ileum; Jejunum; Kidney Calculi; Liver Cirrhosis; Male; Middle Aged; Obesity; Oxalates; Postoperative Complications; Water-Electrolyte Imbalance

There is a definite increased incidence of calculi associated with extensive small bowel disease or resection. Hyperoxaluria appears to play a major role and may be due to increased intestinal oxalate absorption. Forced fluids and dietary discretion are mainstays of stone prophylaxis.

Topics: Bile Acids and Salts; Calcium; Carbon Radioisotopes; Colitis, Ulcerative; Crohn Disease; Enteritis; Humans; Intestine, Small; Intestines; North Carolina; Obesity; Oxalates; Radiotherapy; Urinary Calculi

Epidemiological data indicate an increasing incidence and prevalence of nephrolithiasis (NL) worldwide in the last few decades.. The aim of this study was to compare the clinical and biochemical profiles of recurrent stone formers referred to a Kidney Stone Centre from March 1983 to June 1986 with the one featured by patients seen 25 years later in the same geographical area, Campania, southern Italy.. Idiopathic calcium stone formers made up the large majority of the patient population in both series. Those examined in 2008-11 showed higher age at the onset of NL, higher prevalence of overweight/obesity and higher urinary excretion of oxalate and phosphate compared with those seen in 1983-86. The differences in the urinary biochemical variables remained significant upon accounting for age, gender, creatinine clearance and body mass index (BMI), and were not observed in patients with primary hyperparathyroidism enrolled in the same periods. A greater prevalence of uric acid stone formers was also observed in the 2008-11 population.. The massive epidemics of overweight/obesity and the substantial modifications of dietary habits over the last few decades in most Western countries may be the factors underlying the changing clinical and biochemical profiles of patients with recurrent NL.

Topics: Adult; Biomarkers; Body Mass Index; Calcium; Female; Humans; Male; Nephrolithiasis; Obesity; Overweight; Oxalates; Uric Acid

Patients treated for obesity with jejunoileal bypass (JIB) experienced a marked increased risk of hyperoxaluria, nephrolithiasis, and oxalate nephropathy developing. Jejunoileal bypass has been abandoned and replaced with other options, including Roux-en-Y gastric bypass (RYGB). Changes in urinary lithogenic risk factors after RYGB are currently unknown. Our purpose was to determine whether RYGB is associated with elevated risk of developing calcium oxalate stone formation through increased urinary oxalate excretion and relative supersaturation of calcium oxalate.. A prospective longitudinal cohort study of 24 morbidly obese adults (9 men and 15 women) recruited from a university-based bariatric surgery clinic scheduled to undergo RYGB between December 2005 and April 2007. Patients provided 24-hour urine collections for analysis 7 days before and 90 days after operation. Primary outcomes were changes in 24-hour urinary oxalate excretion and relative supersaturation of calcium oxalate from baseline to 3 months post-RYGB.. Compared with their baseline, patients undergoing RYGB had increased urinary oxalate excretion (31 +/- 10 mg/d versus 41 +/- 18 mg/d; p = 0.026) and relative supersaturation of calcium oxalate (1.73 +/- 0.81 versus 3.47 +/- 2.59; p = 0.030) 3 months post-RYGB in six patients (25%). De novo hyperoxaluria developed. There were no preoperative patient characteristics predictive of development of de novo hyperoxaluria or the magnitude of change of daily oxalate excretion.. This prospective study indicates that RYGB is associated with an earlier increase in urinary oxalate excretion and relative supersaturation of calcium oxalate than previously reported. Additional studies are needed to determine longterm post-RYGB changes in urinary oxalate excretion and identify patients that might be at risk for hyperoxaluria developing.

Topics: Adult; Calcium Oxalate; Cohort Studies; Female; Gastric Bypass; Humans; Hyperoxaluria; Longitudinal Studies; Male; Middle Aged; Nephrolithiasis; Obesity; Oxalates; Prospective Studies; Risk Factors

Topics: Adult; Calcium; Clinical Trials as Topic; Female; Humans; Ileum; Intestinal Absorption; Jejunum; Kidney Calculi; Male; Middle Aged; Obesity; Oxalates; Surgical Procedures, Operative

Ob/ob mice have recently emerged as a model for obesity-related hyperoxaluria as they are obese and excrete more urine oxalate compared to wild type mice. Ob/ob mice are deficient of leptin and develop obesity with hyperphagia and hyperinsulinemia. We hypothesized that insulin resistance and the gut microbiome contribute to hyperoxaluria in ob/ob mice. We developed a new liquid chromatography-mass spectrometry assay for urine oxalate and first compared urine oxalate excretion in ob/ob mice before and after ablation of intestinal bacteria with a standard antibiotic cocktail. We then compared urine oxalate excretion in ob/ob mice before and after leptin replacement or pioglitazone treatment, two maneuvers that reduce insulin resistance in ob/ob mice. Ob/ob mice excreted more oxalate into the urine in a 24-h period compared to wild type mice, but antibiotic, leptin, or pioglitazone treatment did not change urine oxalate excretion in ob/ob mice. Unexpectedly, we found that when food intake was carefully matched between ob/ob and wild type mice, the amount of 24-h urine oxalate excretion did not differ between the two mouse strains, suggesting that ob/ob mice excrete more urine oxalate because of hyperphagia. Since the level of urine oxalate excretion in wild type mice in our study was higher than those reported in prior studies, future work will be needed to standardize the measurement of urine oxalate and to define the range of urine oxalate excretion in wild type mice so that accurate and valid comparisons can be made between wild type mice and ob/ob mice or other mouse models.

Topics: Animals; Anti-Bacterial Agents; Gastrointestinal Microbiome; Hyperoxaluria; Hyperphagia; Insulin Resistance; Leptin; Mice; Mice, Inbred C57BL; Mice, Inbred Strains; Mice, Obese; Obesity; Oxalates; Pioglitazone

A 73-year-old Caucasian female with a history of obesity status post Roux-en-Y gastric bypass (RYGB) surgery presented with generalized weakness and was found to have acute kidney injury (AKI) with a creatinine peak of 9.1 mg/dL above her baseline of 1.2 mg/dL, and anemia with hemoglobin 5.7 g/dl. Kidney biopsy revealed oxalate nephropathy likely related to gastric bypass surgery four years prior. RYGB is a strong risk factor for hyperoxaluria, nephrolithiasis, and oxalate nephropathy which often progresses to end-stage renal disease (ESRD). Meaningful treatment strategies for this disease entity are lacking. We present a case in which dietary and pharmacological management without the use of renal replacement therapy resulted in stabilization of chronic kidney disease (CKD) stage 5 for seven years at the time of this writing.

Topics: Aged; Female; Gastric Bypass; Humans; Hyperoxaluria; Obesity; Oxalates; Postoperative Complications; Renal Insufficiency, Chronic

Hyperoxaluria is a major cause of kidney stone disease. Around half of the oxalate in mammals is supplied from the diet and the other half is endogenously synthesized from glyoxylate. Reduction of hepatic glycolate oxidase (GO) activity is one approach to reduce endogenous production of oxalate. However, there are currently few effective dietary approaches to reduce hepatic GO activity.. In the present study, it is investigated whether restriction of dietary vitamin B2 (VB2) can reduce hepatic GO activity and oxalate excretion in mice with hyperoxaluria induce by hydroxyproline (Hyp) or obesity. It is found that VB2 restriction significantly reduces hepatic GO activity in both the Hyp- and obesity-induced model of hyperoxaluria in mice. However, VB2 restriction reduces urinary oxalate excretion only in the Hyp-treated mice and not the obese mice. This difference could be due to the contribution of endogenous oxalate production that manifests as increased hepatic GO activity in Hyp-treated mice but not obese mice.. Together these results suggest that VB2 restriction could be a new dietary approach to improve hyperoxaluria when endogenous production of oxalate is increased.

Topics: Alcohol Oxidoreductases; Animals; Creatinine; Diet; Hydroxyproline; Hyperoxaluria; Kidney; Male; Mice, Inbred C57BL; Mice, Obese; Obesity; Oxalates; Riboflavin; Riboflavin Deficiency

Most kidney stones are composed of calcium oxalate, and minor changes in urine oxalate affect the stone risk. Obesity is a risk factor for kidney stones and a positive correlation of unknown etiology between increased body size, and elevated urinary oxalate excretion has been reported. Here, we used obese ob/ob (ob) mice to elucidate the pathogenesis of obesity-associated hyperoxaluria. These ob mice have significant hyperoxaluria (3.3-fold) compared with control mice, which is not due to overeating as shown by pair-feeding studies. Dietary oxalate removal greatly ameliorated this hyperoxaluria, confirming that it is largely enteric in origin. Transporter SLC26A6 (A6) plays an essential role in active transcellular intestinal oxalate secretion, and ob mice have significantly reduced jejunal A6 mRNA (- 80%) and total protein (- 62%) expression. While net oxalate secretion was observed in control jejunal tissues mounted in Ussing chambers, net absorption was seen in ob tissues, due to significantly reduced secretion. We hypothesized that the obesity-associated increase in intestinal and systemic inflammation, as reflected by elevated proinflammatory cytokines, suppresses A6-mediated intestinal oxalate secretion and contributes to obesity-associated hyperoxaluria. Indeed, proinflammatory cytokines (elevated in ob mice) significantly decreased intestinal oxalate transport in vitro by reducing A6 mRNA and total protein expression. Proinflammatory cytokines also significantly reduced active mouse jejunal oxalate secretion, converting oxalate transport from net secretion in vehicle-treated tissues to net absorption in proinflammatory cytokines-treated tissues. Thus, reduced active intestinal oxalate secretion, likely secondary to local and systemic inflammation, contributes to the pathogenesis of obesity-associated hyperoxaluria. Hence, proinflammatory cytokines represent potential therapeutic targets.

Topics: Animals; Antiporters; Caco-2 Cells; Cytokines; Disease Models, Animal; Down-Regulation; Humans; Hyperoxaluria; Inflammation Mediators; Intestinal Absorption; Intestinal Secretions; Jejunum; Male; Mice, Inbred BALB C; Mice, Inbred C57BL; Obesity; Oxalates; Secretory Pathway; Sulfate Transporters

Kidney stones is increasingly associated with obesity. With an increasing prevalence of obesity and metabolic syndrome in the past 30 years, urinary oxalate has significantly increased. However, its underlying pathophysiologic mechanisms of hyperoxaluria have not been fully explored. This preclinical study suggests that hyperoxaluria in obesity depends on a complex network of inflammatory responses linked to metabolic outcome. The future mechanistic and clinical investigations must be targeted at elucidating the pathogenetic role of inflammation in obesity induced hyperoxaluria.

Topics: Humans; Hyperoxaluria; Kidney Calculi; Metabolic Syndrome; Obesity; Oxalates; Prevalence

This study sought to explore the influence of different body weight statuses on 24-hour urine compositions in adults without urolithiasis based on a nationwide study of a Chinese Han population.. Twenty-four-hour urine samples from 584 Chinese Han adults without urolithiasis in six cities were analyzed. The participants were divided into four body weight status types according to their body mass indices (BMIs) according to WHO guidelines. The baseline characteristics and 24-hour urine compositions of the standard weight group were compared with those of the underweight, overweight and obese groups. The influences of different body weight statuses on the 24-hour urine compositions were explored using univariate and multivariate logistic regressions.. The numbers of participants in the underweight, standard weight, overweight and obese status groups were 24, 376, 149 and 35, respectively. The overweight and obese groups suffered significantly higher risks of hypertension and diabetes mellitus than the standard weight group. In the univariate analyses, compared with the standard weight group, the overweight group had significantly higher levels of urine citrate (mean difference [MD] = 0.51 mmol, 95% confidence interval [CI]: 0.15-0.87, P = 0.001), potassium (MD = 6.63 mmol, 95% CI: 1.13-12.14, P = 0.01) and magnesium (MD = 0.38 mmol, 95% CI: 0.08-0.69, P = 0.014). Significant increases in urine citrate (MD = 0.85 mmol, 95% CI: 0.01-1.68, P = 0.046), magnesium (MD = 0.69 mmol, 95% CI: 0.13-1.25, P = 0.016) and phosphate (MD = 2.28 mmol, 95% CI: 0.03-4.54, P = 0.047) were found in the obese group. No significant differences were detected between the standard weight and underweight groups. In the multivariate logistic regression analyses, we only observed significantly higher levels of urine potassium (odds ratio [OR] = 1.02, 95% CI: 1.00-1.04, P = 0.03) in the overweight group and phosphate (OR = 1.32, 95% CI: 1.05-1.66, P = 0.018) in the obese group when compared with the standard weight group.. Nonstone-forming adults with overweight or obese statuses were at higher risks of hypertension and diabetes mellitus. Obese nonstone-formers might have a greater risk of urinary stone formation due to increased urinary phosphate excretion. Additionally, underweight status had no influence on 24-hour urine composition.

Topics: Adult; Body Mass Index; Body Weight; Calcium; China; Citric Acid; Humans; Insulin Resistance; Logistic Models; Middle Aged; Multivariate Analysis; Obesity; Overweight; Oxalates; Sodium; Uric Acid; Urolithiasis

Despite guidelines, routine 24-hour urine testing is completed in <10% of high-risk, recurrent stone formers. Using surrogates for metabolic testing, such as key patient characteristics, could obviate the cost and burden of this test while providing information needed for proper stone prevention counseling.. We performed a retrospective study of 392 consecutive patients from 2007 to 2014 with ≥2 lifetime stone episodes, >70% calcium oxalate by mineral analysis, and ≥1 24-hour urine collection. We compared mean 24-hour urine values by age in decades. We used logistic regression and receiver operating characteristic (ROC) curve analysis to assess the predictive ability of age, gender, body mass index (BMI), and comorbidities to detect abnormal 24-hour urine parameters.. The mean age of the cohort was 51 ± 16 years. Older age was associated with greater urinary oxalate (p-trend <0.001), lower urinary uric acid (UA) (p-trend = 0.007), and lower urinary pH (p-trend <0.001). A nonlinear association was noted between age and urinary calcium or citrate (calcium peaked at 40-49 years, p = 0.03; citrate nadired at 18-29 years, p = 0.001). ROC analysis of age, gender, and BMI to predict 24-hour urine abnormalities performed the best for hyperuricosuria (area under the curve [AUC] 0.816), hyperoxaluria (AUC 0.737), and hypocitraturia (AUC 0.740). Including diabetes mellitus or hypertension did not improve AUC significantly.. In our recurrent calcium oxalate cohort, age significantly impacted urinary calcium, oxalate, citrate, and pH. Along with gender and BMI, age can be used to predict key 24-hour urine stone risk results. These data lay the foundation for a risk prediction tool, which could be a surrogate for 24-hour urine results in recurrent stone formers, who are unwilling or unable to complete metabolic testing. Further validation of these findings is needed in other stone populations.

Topics: Adolescent; Adult; Age Factors; Aged; Body Mass Index; Calcium; Calcium Oxalate; Calcium Phosphates; Citrates; Citric Acid; Comorbidity; Diabetes Mellitus; Female; Humans; Hypercalciuria; Hyperoxaluria; Hypertension; Kidney Calculi; Male; Middle Aged; Nephrolithiasis; Obesity; Oxalates; Recurrence; Regression Analysis; Retrospective Studies; Sex Factors; Uric Acid; Urinalysis; Young Adult

Hyperoxaluria after Roux-en-Y gastric bypass (RYGB) is generally attributed to fat malabsorption. If hyperoxaluria is indeed caused by fat malabsorption, magnitudes of hyperoxaluria and steatorrhea should correlate. Severely obese patients, prior to bypass, ingest excess dietary fat that can produce hyperphagic steatorrhea. The primary objective of the study was to determine whether urine oxalate excretion correlates with elements of fat balance in severely obese patients before and after RYGB.. Fat balance and urine oxalate excretion were measured simultaneously in 26 severely obese patients before and 1 year after RYGB, while patients consumed their usual diet. At these time points, stool and urine samples were collected. Steatorrhea and hyperoxaluria were defined as fecal fat >7 g/day and urine oxalate >40 mg/day. Differences were evaluated using paired 2-tailed t tests.. Prior to RYGB, 12 of 26 patients had mild to moderate steatorrhea. Average urine oxalate excretion was 61 mg/day; there was no correlation between fecal fat and urine oxalate excretion. After RYGB, 24 of 26 patients had steatorrhea and urine oxalate excretion averaged 69 mg/day, with a positive correlation between fecal fat and urine oxalate excretions (r = 0.71, P < .001). For each 10 g/day increase in fecal fat output, fecal water excretion increased only 46 mL/day.. Steatorrhea and hyperoxaluria were common in obese patients before bypass, but hyperoxaluria was not caused by excess unabsorbed fatty acids. Hyperphagia, obesity, or metabolic syndrome could have produced this previously unrecognized hyperoxaluric state by stimulating absorption or endogenous synthesis of oxalate. Hyperoxaluria after RYGB correlated with steatorrhea and was presumably caused by excess fatty acids in the intestinal lumen. Because post-bypass steatorrhea caused little increase in fecal water excretion, most patients with steatorrhea did not consider themselves to have diarrhea. Before and after RYGB, high oxalate intake contributed to the severity of hyperoxaluria.

Topics: Adult; Aged; Dietary Fats; Feces; Female; Gastric Bypass; Humans; Hyperoxaluria; Hyperphagia; Male; Middle Aged; Obesity; Oxalates; Severity of Illness Index; Steatorrhea

There is conflicting evidence about the role of obesity in paediatric nephrolithiasis. This Polish study explored the influence of nutritional status and lipid disturbances on urinary lithogenic factors and the risk of kidney stone formation in children and adolescents from three to 18 years of age.. We carried out serum lipid profile evaluations and 24-h urine chemistry analyses on 493 overweight/obese paediatric participants (mean age 13 years) without nephrolithiasis and 492 healthy normal weight sex and age-matched controls.. A third (33%) of the study group had blood lipid disturbances, with more acidic urine, lower urinary citrate excretion and a higher fraction of ionised calcium and higher Bonn Risk Index than the controls. The participants' body mass index standard deviation score (BMI Z-score) was positively correlated with urinary oxalate and uric acid and negatively correlated with citrate excretion. Total cholesterol, low-density lipoprotein cholesterol and triglycerides correlated negatively with citraturia, while high-density lipoprotein cholesterol correlated positively.. The main factor that predisposed overweight and obese children to kidney stones was hypocitraturia. Urinary citrate excretion was related to both BMI Z-scores and all lipid fraction abnormalities. However, hypercholesterolaemia and particularly low-density lipoprotein hypercholesterolaemia seemed to play a major role.

Topics: Adolescent; Body Mass Index; Calcium; Case-Control Studies; Child; Child, Preschool; Citric Acid; Cross-Sectional Studies; Dyslipidemias; Female; Humans; Kidney Calculi; Male; Nutritional Status; Obesity; Oxalates; Poland; Prospective Studies; Risk Factors; Uric Acid

Obese patients have an increased risk of kidney stones, and several studies have identified specific urinary derangements on 24-hour collections. The objective of this study was to assess obese and super-obese stone formers, and their compliance with dietary modifications over time, based on 24-hour urine outcomes.. A retrospective review was performed searching for all stone formers who completed a 24-hour urine collection before and after dietary counseling for stone prevention. Patients were excluded if placed on medical therapy in addition to dietary therapy. Patients were divided in three main groups according to their body mass index (BMI): 30, 30-40, and >40 kg/m(2). Demographic data and 24-hour urine stone risk parameters (volume, sodium, uric acid, citrate, and oxalate) were assessed. Initial 24-hour urine results were compared to follow-up results after dietary counseling. Then, the outcomes from each group were compared to each other.. Two hundred and fourteen stone formers (67% male) were identified with a mean age of 49.5±15.0 years. One hundred twenty-eight (59.8%) patients had BMI <30 kg/m(2), 61 (28.5%) between 30-40 kg/m(2), and 25 (11.7%) >40 kg/m(2). Among patients with BMI <30 kg/m(2), there were significant improvements in all urinary parameters (p<0.001) as well as in the group with BMI between 30 to 40 kg/m(2) (p=0.02 for oxalate, p<0.001 for other parameters). Among super-obese patients, there were significant improvements in the urinary volume (p=0.03), sodium (p<0.001), uric acid (p=0.001), and oxalate (p<0.001). There were no significant differences in the improvements observed in the urinary volume (p=0.69), sodium (p=0.08), uric acid (p=0.17), and citrate levels (p=0.97) between the groups.. Dietary recommendations can be an equally effective strategy in decreasing the risk or stone recurrence in obese and super-obese kidney stone formers as it is in those who are not obese.

Topics: Adult; Body Mass Index; Citric Acid; Dietary Supplements; Female; Follow-Up Studies; Humans; Kidney Calculi; Male; Middle Aged; Obesity; Oxalates; Retrospective Studies; Sodium; Uric Acid

We determined the effect of dietary fat and oxalate on fecal fat excretion and urine parameters in a rat model of Roux-en-Y gastric bypass surgery.. Diet induced obese Sprague-Dawley® rats underwent sham surgery as controls (16), or Roux-en-Y gastric bypass surgery (19). After recovery, rats had free access to a normal calcium, high fat (40%) diet with or without 1.5% potassium oxalate for 5 weeks and then a normal (10%) fat diet for 2 weeks. Stool and urine were collected after each period. Fecal fat was determined by gas chromatography and urine metabolites were evaluated by assay spectrophotometry.. Daily fecal fat excretion remained low in controls on either diet. However, Roux-en-Y gastric bypass rats ingested a food quantity similar to that of controls but had eightfold higher fecal fat excretion (p <0.001) and heavier stools (p = 0.02). Compared to controls, gastric bypass rats on the high fat diet with potassium oxalate had a fivefold increase in urine oxalate excretion (p <0.001), while gastric bypass rats without potassium oxalate had a twofold increase in urine calcium (p <0.01). Lowering dietary fat in gastric bypass rats with potassium oxalate led to a 50% decrease in oxalate excretion (p <0.01), a 30% decrease in urine calcium and a 0.3 U increase in urine pH (p <0.001).. In this Roux-en-Y gastric bypass model high fat feeding resulted in steatorrhea, hyperoxaluria and low urine pH, which were partially reversible by lowering the dietary fat and oxalate content. Roux-en-Y gastric bypass rats on normal fat and no oxalate diets excreted twice as much oxalate as age matched, sham operated controls. Although Roux-en-Y gastric bypass hyperoxaluria appears primarily mediated by gut and diet, secondary causes of oxalogenesis from liver or other mechanisms deserve further exploration.

Topics: Animals; Dietary Fats; Disease Models, Animal; Feces; Gastric Bypass; Hyperoxaluria; Male; Obesity; Oxalates; Postoperative Complications; Random Allocation; Rats; Rats, Sprague-Dawley; Reference Values; Risk Assessment; Steatorrhea; Treatment Outcome; Urinalysis

Topics: Anti-Obesity Agents; Canada; Chemical and Drug Induced Liver Injury; Databases, Factual; France; Humans; Kidney Diseases; Lactones; Obesity; Orlistat; Oxalates

Childhood obesity is becoming a worldwide epidemic and its metabolic and cardiovascular complications may already be evident at a young age. Several epidemiologic studies in adults have clearly demonstrated that obesity and overweight increase the risk of kidney disease and urolithiasis.. The purpose of this study was to evaluate the relationship between overweight and obesity and urolithiasis risk factors in children.. The main kidney stones risk factors in urine such as calcium concentration, oxalate concentration, citrate concentration, pH of urine as well as BRI (Bonn Risk Index) were analyzed in 249 overweight and obese children (study group) and in 281 children with normal weight (control) at the age of 3 to 18 years old.. In the study group the mean oxalate concentration was significantly higher than in the control (0.52±0.48 vs. 0.26±0.12; p <0.05). The mean calcium concentration of overweight/obese patients was higher than that of normal body weight and the difference was close to statistically significant (3.23±2.55 vs 2.58±1.59; p=0.0537). The mean urine pH in the study group was 6.28±0.46 and was significantly lower (p <0.05) than the mean urine pH in the control, witch was 6.40±0.47. The mean citrate concentration among overweight/obese patients was significantly lower than in control (431,2±309,5 vs. 637,2±310,7; p <0.05).. Our results suggest that obesity or overweight at a young age are associated with an increased risk of kidney stones. Weight loss might be explored as a potential treatment to prevent kidney stone formation.

Topics: Adolescent; Calcium; Case-Control Studies; Causality; Child; Child, Preschool; Citrates; Comorbidity; Female; Humans; Hydrogen-Ion Concentration; Male; Obesity; Overweight; Oxalates; Risk Factors; Urine; Urolithiasis

We present here the anatomy and histopathology of kidneys from 11 patients with renal stones following small bowel resection, including 10 with Crohn's disease and 1 resection in infancy for unknown cause. They presented predominantly with calcium oxalate stones. Risks of formation included hyperoxaluria (urine oxalate excretion greater than 45 mg per day) in half of the cases, and acidic urine of reduced volume. As was found with ileostomy and obesity bypass, inner medullary collecting ducts (IMCDs) contained crystal deposits associated with cell injury, interstitial inflammation, and papillary deformity. Cortical changes included modest glomerular sclerosis, tubular atrophy, and interstitial fibrosis. Randall's plaque (interstitial papillary apatite) was abundant, with calcium oxalate stone overgrowth similar to that seen in ileostomy, idiopathic calcium oxalate stone formers, and primary hyperparathyroidism. Abundant plaque was compatible with the low urine volume and pH. The IMCD deposits all contained apatite, with calcium oxalate present in three cases, similar to findings in patients with obesity bypass but not an ileostomy. The mechanisms for calcium oxalate stone formation in IMCDs include elevated urine and presumably tubule fluid calcium oxalate supersaturation, but a low calcium to oxalate ratio. However, the mechanisms for the presence of IMCD apatite remain unknown.

Topics: Abdomen; Adult; Apatites; Biopsy; Calcium Oxalate; Calculi; Digestive System Surgical Procedures; Female; Humans; Hyperoxaluria; Hyperparathyroidism, Primary; Ileostomy; Intestine, Small; Intestines; Kidney; Kidney Calculi; Kidney Cortex; Kidney Diseases; Male; Obesity; Oxalates; Young Adult

In recent decades there has been an increasing prevalence of urolitithiasis in many western countries and at the same time there has been an increasing progression of obesity that has reached epidemic proportions. The aim of the present study was to assess the influence of overweight/obesity on the metabolic risk factors for renal stone formation. We studied 799 renal stone formers (462 men and 337 women) who came to the clinic for metabolic risk factors evaluation. They were all studied with a standard protocol (two 24-h urine collections and serum parameters). They were divided according to their BMI in normal (BMI < 25) overweight (BMI 25-29.9) and obese (BMI > 30). Low-weight individuals were excluded. Overall, 487 of 799 (60.9%) patients had a BMI > 25, including 40.6% overweight and 20.3% obese. Among women 55.2% had normal weight, 25.5 were overweight, and 19.3% were Obese; among men 27.3% had normal weight, 51.7 were overweight, and 21% were obese. Age increased significantly with increasing BMI both in men and women. In women there was a significant increase in the excretion of oxalate, uric acid, phosphorus, creatinine, and sodium with increasing BMI, but no change was observed in calcium, magnesium, citrate, and urine pH. In men there was a significant increase in the excretion of oxalate, uric acid, creatinine, phosphorus, sodium, magnesium, and citrate with increasing BMI, no change in urinary calcium and significant progressive decrease in urinary pH. In this population of stone formers there was a high prevalence of overweight/obesity (60.9%). Both in men and women we found a significant increase in the urinary excretion of two promoters of stone formation, oxalate, and uric acid but no change in urinary calcium. There was either no change or increase in magnesium and citrate, inhibitors of crystallization, and a significant decrease in urine pH only in men.

Topics: Adult; Calcium; Citric Acid; Creatinine; Female; Humans; Hydrogen-Ion Concentration; Magnesium; Male; Middle Aged; Obesity; Overweight; Oxalates; Phosphorus; Retrospective Studies; Risk Factors; Sex Characteristics; Sodium; Uric Acid; Urolithiasis

Nephrolithiasis and renal failure secondary to severe hyperoxaluria were complications of jejunoileal bypass for obesity, leading to the discontinuation of this procedure in the United States in 1980. Bariatric procedures currently in use have not been adequately evaluated for this complication.. We compared 24-hour urine chemistry studies of 132 patients with nephrolithiasis who had undergone bariatric surgery with the urine chemistry studies of patients who had undergone jejunoileal bypass, those with routine kidney stones and normal subjects. The primary aim was to determine if hyperoxaluria developed in patients who underwent bariatric surgery and had kidney stones as had been seen with jejunoileal bypass.. Patients who have undergone modern bariatric surgery had an adjusted mean urine oxalate excretion of 83 mg per day compared to 39 mg per day for routine kidney stone formers and 34 mg per day for normal subjects (p <0.001 for both comparisons), but not quite as high as that found in patients treated with jejunoileal bypass (102 mg per day, p <0.001). Urine supersaturation of calcium oxalate, the main driving force for calcium oxalate stone formation, was higher in patients treated with bariatric surgery compared to routine kidney stone formers and normal subjects (p <0.001 for both comparisons).. Hyperoxaluria is the most significant abnormality of urine chemistry studies in patients with kidney stones who have undergone bariatric surgery. Many of these patients have a degree of hyperoxaluria that could lead to kidney failure. Further studies are required to determine the prevalence of this problem in patients who have undergone bariatric surgery.

Topics: Bariatric Surgery; Female; Humans; Hyperoxaluria; Jejunoileal Bypass; Kidney Calculi; Male; Multivariate Analysis; Obesity; Oxalates

Greater body mass index (BMI) is a risk factor for kidney stones. However, the relation between BMI and the urinary excretion of many lithogenic factors remains unclear.. We studied urine pH, urine volume, and 24-hour urinary excretion of calcium, oxalate, citrate, uric acid, sodium, magnesium, potassium, phosphate, and creatinine in stone-forming and non-stone-forming participants in the Health Professionals Follow-Up Study (599 stone-forming and 404 non-stone-forming men), Nurses' Health Study (888 stone-forming and 398 non-stone-forming older women), and Nurses' Health Study II (689 stone-forming and 295 non-stone-forming younger women). Each cohort was divided into quintiles of BMI. Tests of linear trend were conducted by 1-way analysis of variance. Linear regression models were adjusted for age, history of stone disease, dietary intake, and urinary factors.. Participants with greater BMIs excreted more urinary oxalate (P for trend

Topics: Adult; Body Mass Index; Calcium; Calcium Oxalate; Citrates; Comorbidity; Creatinine; Diabetes Mellitus; Female; Humans; Hydrogen-Ion Concentration; Hypertension; Kidney Calculi; Linear Models; Magnesium; Middle Aged; Obesity; Oxalates; Phosphates; Potassium; Risk Factors; Sodium; Urine

The aim of the study was to assess the influence of overweight and obesity on the risk of calcium oxalate stone formation.. BMI, 24-hour urine, and serum parameters were evaluated in idiopathic calcium oxalate stone formers (363 men and 164 women) without medical or dietetic pretreatment.. Overweight and obesity were present in 59.2% of the men and in 43.9% of the women in the study population. Multiple linear regression analysis revealed a significant positive relationship between BMI and urinary uric acid, sodium, ammonium, and phosphate excretion and an inverse correlation between BMI and urinary pH in both men and women, whereas BMI was associated with urinary oxalate excretion only among women and with urinary calcium excretion only among men. Serum uric acid and creatinine concentrations were correlated with BMI in both genders. Because no association was established between BMI and urinary volume, magnesium, and citrate excretion, inhibitors of calcium oxalate stone formation, the risk of stone formation increased significantly with increasing BMI among both men and women with urolithiasis (p = 0.015). The risk of calcium oxalate stone formation, median number of stone episodes, and frequency of diet-related diseases were highest in overweight and obese men.. Overweight and obesity are strongly associated with an elevated risk of stone formation in both genders due to an increased urinary excretion of promoters but not inhibitors of calcium oxalate stone formation. Overweight and obese men are more prone to stone formation than overweight women.

Topics: Adult; Body Mass Index; Calcium; Calcium Oxalate; Citric Acid; Creatinine; Diet; Female; Humans; Hydrogen-Ion Concentration; Linear Models; Magnesium; Male; Middle Aged; Obesity; Oxalates; Sex Characteristics; Uric Acid; Urinary Calculi; Urine

Topics: Biliary Tract Surgical Procedures; Gastrectomy; Humans; Intestine, Small; Obesity; Oxalates; Pancreas

The intestinal permeation and 6-hour urinary recovery of small, multisized tracers, polyethyleneglycol 400 (PEG 400), was used to characterize gut permeability in nine patients after bypass surgery for morbid obesity and in ten healthy volunteers. In the patients, who also had hyperoxaluria, the urinary recovery of ingested PEG 400 was lower than in the healthy persons (10.9 and 24.7%). The patients also showed stronger intestinal exclusion of the larger polymers within the PEG 400.

Topics: Adult; Creatinine; Female; Glomerular Filtration Rate; Humans; Ileum; Intestinal Mucosa; Jejunum; Male; Middle Aged; Molecular Weight; Obesity; Oxalates; Polyethylene Glycols; Uric Acid

Nine cases of the distal type of renal tubular acidosis (RTA) following intestinal bypass were found. Diagnosis was based on inability to acidify the urine to pH values below 5.40 despite systemic acidosis. Acidosis, if not present, was induced by giving ammonium chloride 0.1 g/kg body weight. Patients were examined for diseases known to cause RTA but no already known etiological factor was found. Hyperoxaluria was found in eight of the nine cases with RTA, while not present in patients without RTA or in obese control patients. A causal relationship between hyperoxaluria and RTA is suggested though not proved. Cases reported in the literature of renal damage following bypass are summarized and discussed in relation to presence of hyperoxaluria and RTA.

Topics: Acidosis, Renal Tubular; Adult; Female; Humans; Hydrogen-Ion Concentration; Ileum; Jejunum; Kidney Function Tests; Middle Aged; Obesity; Oxalates; Postoperative Complications

Topics: Adult; Enteritis; Female; Humans; Intestinal Absorption; Intestine, Small; Male; Middle Aged; Obesity; Oxalates; Urinary Calculi

The urinary excretion of oxalate, calcium, citrate, magnesium, urate and creatinine and the inhibition of calcium oxalate crystal growth were determined in 30 patients operated with three different types of jejunoileal bypass. In addition the ion-activity products of calcium oxalate and calcium oxalate saturation were calculated. 15 of the patients had formed urolithiasis postoperatively. The patients were investigated on an out-patient basis with their ordinary diet. All patients had hyperoxaluria. The oxalate excretion did not seem to decrease with time after operation. The patients operated with a biliointestinal shunt had a significantly higher excretion of oxalate than those with the other two types of operation, indicating that variations in the anatomy of the small intestine after jejunoileal bypass might result in different absorption of oxalate or oxalate precursors. Urinary oxalate, calcium oxalate saturation and ion-activity products were higher whereas the excretion of calcium, magnesium and citrate was lower in patients than in controls. The urine volumes, excretion of creatinine and urate and inhibition of calcium oxalate crystal growth were equal in patients and controls. Analogous urine composition was found in patients both with and without urolithiasis with the exception of a higher magnesium excretion observed in stone formers.

Topics: Adult; Calcium; Citrates; Creatinine; Female; Humans; Ileum; Jejunum; Magnesium; Male; Middle Aged; Obesity; Oxalates; Postoperative Complications; Uric Acid; Urinary Calculi; Urine

Previous studies have shown that the severity of enteric hyperoxaluria can be reduced in hospitalized patients who receive a diet low in oxalate and fat. Little is known of the value of such a diet in the patients' home conditions. Ten patients with hyperoxaluria (greater than 0.45 mmol/24 h) following jejuno-ileal bypass were therefore studied while on their ordinary diet and also on a diet with low-oxalate, low-fat content. The mean urinary excretion of oxalate decreased during the dietary treatment from 1.1 to 0.7 mmol/24 h. The diet was demanding, though not unfeasible for the patients. Careful and regular dietary information, preferably by a dietitian, is recommended in such cases.

Topics: Adult; Dietary Fats; Female; Humans; Ileum; Intestinal Absorption; Jejunum; Male; Middle Aged; Obesity; Oxalates; Oxalic Acid; Postoperative Complications

The urinary excretion of oxalate, calcium, magnesium and citrate as well as the inhibition of calcium oxalate crystal growth in diluted urine was studied in seven patients with hyperoxaluria following jejunoileal bypass. The study was performed on an outpatient basis before and during daily administration of 38 or 113 mmol calcium, 28 mmol of aluminum, 20 mmol of magnesium or 16 g of cholestyramine. Each substance was administered for seven days with a free interval of at least seven days. The mean urinary oxalate excretion was not reduced with any of these regimens. Administration of 38 mmol of calcium per day resulted in increased oxalate and magnesium excretion. Increased excretion of both calcium and citrate was observed during administration of 113 mmol of calcium per day. Calcium and magnesium excretion was increased with aluminium. An increased magnesium excretion was also observed during administration of magnesium, resulting in a decreased calcium/ magnesium ratio. Cholestyramine resulted in increased oxalate and decreased citrate excretion.

Topics: Adult; Aluminum; Calcium; Calcium Gluconate; Cholestyramine Resin; Female; Humans; Ileum; Intestinal Absorption; Jejunum; Lactates; Lactic Acid; Magnesium; Magnesium Oxide; Male; Middle Aged; Obesity; Oxalates; Oxalic Acid; Postoperative Complications

Balance studies and oxalate loading tests were carried out in order to define the pathogenesis of hyperoxaluria in 8 patients with jejunoileal bypass surgery for severe obesity; two healthy volunteers were also studied. In the bypass patients, urinary oxalate was markedly elevated (118 +/- 43 mg/day, mean +/- SD) when they were on a high oxalate diet (252 mg/day). Hyperabsorption of dietary oxalate was confirmed by the markedly increased urinary recovery of [14C]oxalate given in a test meal. In addition, the oxalate radioactivity was excreted in urine far more slowly than in healthy volunteers, suggesting that the colon was a major site of oxalate absorption. Elevated urinary oxalate excretion persisted, averaging 38 +/- 12 mg/day, despite ingestion of a very low oxalate diet (approximately 6 mg/day), suggesting that the diet contained "oxalogenic" substances other than preformed dietary oxalate which also contributed to dietary oxalate in these patients. Urinary oxalate decreased in 7 of 8 patients, however, when protein-rich foods were removed from the diet, suggesting that at least one dietary factor was digestive products of protein or creatinine. These results confirm the current view that in patients with hyperoxaluria secondary to jejunoileal bypass, the majority of urinary oxalate derives from dietary oxalate that is absorbed from the colon. Tissue or bacterial production of oxalate or an oxalate precursor from dietary constituents associated with protein, however, also appears to contribute to urinary oxalate. The results provide an explanation for the reported difficulty of eliminating secondary hyperoxaluria by restriction of dietary oxalate alone.

Topics: Adult; Colon; Diet; Dietary Proteins; Female; Humans; Ileum; Intestinal Absorption; Intestines; Jejunum; Male; Middle Aged; Neomycin; Obesity; Oxalates; Oxalic Acid

Hyperoxaluria occurs in most patients after the conventional jejunoileal bypass procedure for obesity. The mechanism of hyperoxaluria is complex, involving persistence of dietary oxalate in solution as well as increased colonic permeability to oxalate. Endogenous oxalate formation also contributes to hyperoxaluria. Treatment is unsatisfactory and involves a low-oxalate diet and simultaneous administration of agents which bind oxalate and bile acids, such as aluminum hydroxide. Hyperoxaluria was not present in 21 of 22 patients who had undergone the pancreato-biliary bypass procedure.

Topics: Biliary Tract Surgical Procedures; Colon; Diet; Dietary Fats; Humans; Ileum; Jejunum; Obesity; Oxalates; Oxalic Acid; Pancreas; Permeability; Postoperative Complications

A 38-year-old woman suffered rapid onset of renal failure between 11 and 15 months after undergoing a jejunoileal bypass for morbid obesity. Microscopic examination of renal biopsy specimens revealed oxalosis and severe tubulointerstitial nephritis. Immunofluorescence microscopy disclosed linear staining of tubular basement membranes with antisera to IgG and C3, which suggests antitubular basement membrane disease, a side effect not previously recognized with jejunoileal bypass. Possible mechanisms leading to the formation of these antibodies include (1) oxalate damage to renal tubules with release of tubular basement membrane antigens, and (2) bacterial overgrowth in the bypass segment, with mucosal damage and release of intestinal mucosal antigens that share antigenetic determinants with renal proximal tubules. Anti-tubular basement membrane disease may be an additional mechanism that produces or enhances renal damage in patients with jejunoileal bypass.

Topics: Adult; Antibodies; Basement Membrane; Chronic Disease; Complement C3; Female; Humans; Ileum; Immunoglobulin G; Jejunum; Kidney Tubules; Microscopy; Microscopy, Electron; Nephritis, Interstitial; Obesity; Oxalates; Postoperative Complications

Topics: Fluorescent Antibody Technique; Humans; Intestines; Kidney; Kidney Diseases; Kidney Glomerulus; Obesity; Oxalates; Oxalic Acid; Postoperative Complications

Topics: Animals; Calcium Carbonate; Calcium Oxalate; Crystallization; Humans; Hypocalcemia; Ileum; Intestinal Absorption; Jejunum; Kidney Calculi; Obesity; Oxalates; Rats; Surgical Procedures, Operative

Intestinal absorption of oxalate can be judged from the urinary excretion of orally administered [14C]oxalate. Fifteen normal subjects, 21 patients with "idiopathic" calcium oxalate stone disease and a high oxalate excretion, four patients operated with ileocecal resection, and seven patients operated with jejunoileal bypass were so investigated. We saw no significant difference in the amount of isotope excreted by normal subjects and idiopathic stone formers; 13.6% (SD 5.9%) and 14.4% (SD 6.5%), respectively, of the administered dose was accounted for in the urine. The patients with resection or bypass showed a quite different pattern of isotope excretion, and 18.3% (SD 7.0%) and 36.8% (SD 14.0%), respectively, of the isotope was accounted for in the urine.

Topics: Calcium Oxalate; Cecum; Female; Humans; Ileum; Intestinal Absorption; Intestines; Jejunum; Male; Obesity; Oxalates; Oxalic Acid; Urinary Calculi

The urinary excretion of oxalate, calcium, magnesium and creatinine was investigated in 21 outpatients who underwent jejunoileal bypass operation 6-9 years previously. Furthermore, a urinary stone index expressed as the quotient (calcium X oxalate)/(magnesium X creatinine) (mmol/mol) was calculated. The oxalate excretion exceeded normal ranges in 20 patients (1.20 +/- 0.55 mmol/24 h), and the stone index was found critically high in all. Daily administration of 1,100 mg ionized calcium in 17 of these patients die not change the urinary excretion of oxalate, calcium and magnesium separately, but the stone index was reduced significantly suggesting some preventive effect of calcium on the tendency of stone formation after jejunoileal bypass.

Topics: Adult; Calcium; Creatinine; Female; Humans; Ileum; Jejunum; Magnesium; Male; Obesity; Oxalates; Oxalic Acid; Urinary Calculi

A 32-year-old women was treated for overweight by gastrointestinal bypass surgery. Following surgery, repeated calcium oxalate nephrolithiasis was observed and secondary hyperoxaluria was diagnosed. Treatment with low oxalate and fat diet resulted in normal urinary oxalic acid excretion; no further stone formation was observed.

Topics: Adult; Dietary Fats; Female; Humans; Ileum; Kidney Calculi; Obesity; Oxalates; Oxalic Acid; Postoperative Complications

Fourteen patients with jejunoileal bypass for obesity were treated for one week with a calcium supplement of 3g daily. During this period diarrhoea was significantly (P < 0.005) reduced by 23 per cent (97 per cent confidence limits: 7-46 per cent). Ten of the patients had hyperoxaluria (median value 961 mumol/24 h; range 633-2742 mumol/24 h). The treatment with calcium significantly (P < 0.005) decreased the concentration of oxalate in urine by 23 per cent (98 per cent confidence limits: -5-+54 per cent). The calcium supplement did not increase urinary calcium-excretion rate or albumin-corrected serum calcium.

Topics: Adult; Calcium; Diarrhea; Feces; Humans; Ileum; Jejunum; Middle Aged; Obesity; Oxalates

Topics: Adult; Calcium; Celiac Disease; Female; Humans; Ileum; Intestinal Absorption; Jejunum; Lipid Metabolism; Male; Middle Aged; Obesity; Oxalates; Postoperative Complications; Prospective Studies

The effect of oral calcium on oxalate absorption was studied in eight patients with secondary hyperoxaluria after jejunoileal bypass for morbid obesity during a standardized diet with a fixed supply of fat, calcium, and oxalate. A supplementary calcium dose of 2000 mg/day reduced renal oxalate excretion from 119 to 60 mg/24 h (median values, p < 0.01). Correspondingly, 14C-oxalate absorption decreased from 28% to 9% (p < 0.01). No statistically significant increase in urinary calcium was observed. The study shows that renal oxalate excretion in patients with enteric hyperoxaluria can be reduced by oral calcium. However, we doubt that it has any practical, clinical importance.

Topics: Adolescent; Adult; Calcium; Female; Humans; Ileum; Jejunum; Malabsorption Syndromes; Male; Middle Aged; Obesity; Oxalates; Postoperative Complications

In order to investigate the effect on urinary oxalic acid excretion, ten patients with jejunoileostomy for morbid obesity were treated with oral calcium. We found a statistically significant decrease. The investigation suggests that the oral administration of calcium alone is not sufficient, in a dosage of 900 mg daily, to normalize the urinary oxalate excretion. The indications for calcium therapy in this group of patients is discussed.

Topics: Administration, Topical; Calcium; Drug Evaluation; Humans; Intestine, Small; Obesity; Oxalates; Postoperative Complications

Oxalate nephrosis resulted in progressive renal failure in 4 patients after jejunoileal bypass for morbid obesity. In general, increased levels of oxalates in the blood and urine of such patients result from enhanced absorption of exogenous oxalates. Urinary calculous formation is determined further by concomitant deficiency of inhibitor substances, whereas oxalate nephrosis probably occurs as a result of oxalate deposition in renal interstitium via the blood stream. Clinical manifestations of oxalate nephrosis include pain, infection, hematuria and renal failure. Routine postoperative renal function studies and early renal biopsy in suspicious cases are urged to establish early diagnosis. Continued deterioration of renal function, despite therapy with oxalate restruction and oxalate binding agents, indicates a reversal of the bypass to preserve unaffected renal substance.

Topics: Adult; Female; Humans; Ileum; Jejunum; Kidney; Kidney Diseases; Male; Middle Aged; Nephrosis; Obesity; Oxalates; Postoperative Complications

Topics: Humans; Ileum; Jejunum; Kidney Calculi; Obesity; Oxalates; Postoperative Complications

Topics: Calcium, Dietary; Female; Humans; Intestine, Small; Jejunum; Obesity; Oxalates

Intestinal bypass for obesity can be justified only if the risks of excess weight are higher than those of the surgery. Indications for this surgery need to be carefully defined and the patient and family should clearly understand the potential risks and benefits. Weight loss results from a decrease in food intake, altered taste preferences, and malabsorption. The benefits of this treatment are permanent weight loss, improved psychosocial function, and a reduction in medical morbidity. The potential risks consist of mortality, a variety of postoperative complications, liver failure, renal stones, and the consequences of bacterial overgrowth in the defunctionalized bowel. This operation trades the consequences of a short bowel for obesity and should only be undertaken where a skilled team of surgeons, internists, and psychiatrists are available and able to provide the necessary preoperative and postoperative managements.

Topics: Body Weight; Feeding Behavior; Female; Humans; Ileum; Intestinal Absorption; Intestines; Jejunum; Kidney Calculi; Liver Diseases; Male; Nutrition Disorders; Obesity; Oxalates; Postoperative Complications; Psychology, Social

Gastrointestinal anatomy and function has been studied prospectively in 12 patients undergoing jejunoileal bypass surgery in order to investigate the adaptive response of the intestinal mucosa. The total thickness of the jejunal mucosa did not change after surgery, but the crypts became relatively deeper, suggesting a more rapid turnover of gastrointestinal cells. The absorption of oxalate was depressed in the immediate postoperative period but had improved toward preoperative levels by 6 months. Vitamin B12 absorption also declined postoperatively, and increased thereafter in the patients with an end-to-end jejunoileostomy, but showed a much smaller recovery in the group with an end-to-side anastomosis. The cholesterol concentration (lithogenicity) of the duodenal bile rose by 30% in the first 3 weeks after surgery, but had returned to preoperative levels by 6 months. The segmental absorption of glucose across the jejunum declined after surgery. Caloric intake also declined, whether measured as the quantity of food that patients elected to eat over a 24-hr period, or as the quantity of a liquid lunch which they consumed over a 20-min period. The level of basal gastric acid was increased postoperatively but the maximal output after histamine stimulation was not. The gastrin response to a standard liquid meal was also significantly increased after surgery. Enteroglucagon secretion showed an increase in 3 weeks and a further increase by 6 months after intestinal bypass surgery. The significance of these changes to intestinal adaptations is discussed.

Topics: Bile Acids and Salts; Cholesterol; Duodenum; Energy Intake; Gastric Juice; Gastrins; Glucagon; Glucose; Humans; Ileum; Intestinal Absorption; Intestinal Mucosa; Intestine, Small; Jejunum; Obesity; Oxalates; Phospholipids; Vitamin B 12

Patients with ileal disease, ileal resection, and jejunoileal bypass are at increased risk of forming calcium oxalate renal calculi because of enhanced absorption of dietary oxalate. Intraluminal solubility of oxalate is an important determinant for hyperabsorption and may be regulated by intraluminal concentration of calcium and fatty acids. Malabsorbed bile salts and fatty acids may alter intestinal permeability, leading to increased passive diffusion of oxalate. Management includes a diet low in oxalate and fat content, dietary calcium of 750 mg/day, and cholestyramine.

Topics: Bile Acids and Salts; Calcium; Calcium, Dietary; Celiac Disease; Cholestyramine Resin; Dietary Fats; Fatty Acids; Humans; Ileum; Intestinal Diseases; Intestinal Mucosa; Jejunum; Kidney Calculi; Obesity; Oxalates

Topics: Aluminum Hydroxide; Calcium; Cations, Divalent; Deoxycholic Acid; Dietary Fats; Humans; Ileum; Intestinal Absorption; Jejunum; Obesity; Oxalates; Ricinoleic Acids

A review of the problems associated with extensive jejunoileal bypass for morbid obesity in a series of 175 carefully selected patients is presented. Five postoperative deaths occurred (3%). Nonfatal complications occurred in 21%, with wound infections (14 patients) being the most common. Good results marked by weight reduction to the range of ideal weight without significant electrolyte or metabolic aberrations was observed in 82% of the patients receiving the current dimensional modificatiom of end-to-end jejunoileal bypass (30 cm to 20cm). An additional 13% had fair results and only 5% had poor results. There were six deaths during follow-up: liver failure in four patients (secondary to alcohol abuse in two), myocardial infarction in one, and one from unknown causes. Bypass reversal was necessary for refractory liver failure in three patients (two from alcohol abuse), and for persistent diarrhea with secondary electrolyte depletion in two patients. One of these patients was complicated by severe emotional instability. This experience suggests that the majority of carefully selected patients will have a good response to jejunoileal bypass.

Topics: Adolescent; Adult; Anemia; Avitaminosis; Body Weight; Cholelithiasis; Diarrhea; Electrolytes; Fatty Liver; Female; Follow-Up Studies; Gout; Humans; Hypoproteinemia; Ileum; Jejunum; Kidney Calculi; Liver Diseases; Male; Middle Aged; Obesity; Oxalates; Postoperative Complications

A 45-year-old man underwent a jejunoileal shunt procedure for obesity. Twenty months later he developed severe oxalosis and chronic renal failure, which required maintenance hemodialysis. The sequential observation of two biopsy specimens and the necropsy (over a span of 39 months) suggests that oxalate deposition caused tubular obstruction and destruction with subsequent atrophy of nephrons. This indicates that patients undergoing intestinal bypass are at risk for developing irreversible renal failure due to enteric hyperoxaluria.

Topics: Humans; Ileum; Jejunum; Kidney Failure, Chronic; Kidney Tubules; Male; Metabolic Diseases; Middle Aged; Obesity; Oxalates; Postoperative Complications

Initially, diarrhea is almost universal but becomes self-limited unless the patient persists in overeating. Weight loss averages 75 to 100 lb the first year, with a stable level generally achieved after 18 months. Among the serious potential complications are enteritis, kidney stones, gallstones, and hepatopathology. Some can be anticipated and kept at bay by prophylactic measures like high-protein intake.

Topics: Anti-Bacterial Agents; Arthritis; Body Temperature Regulation; Cholelithiasis; Dermatitis; Diarrhea; Dietary Proteins; Enteritis; Fatty Liver; Humans; Ileum; Intestinal Absorption; Kidney Calculi; Liver Diseases; Obesity; Oxalates; Postoperative Complications

Urinary calculi, predominantly of oxalate composition, have been noted in 10 to 14% of a large series of morbidly obese patients after jejunoileal intestinal bypass at this institution. Physical and metabolic changes after bypass surgery, including the presence of hyderoxaluria, hyperuricemia, and fluid and electrolyte disturbances are reviewed in their possible relationship to this increased incidence of urolithiasis.

Topics: Adolescent; Adult; Bile Acids and Salts; Diet; Female; Humans; Ileum; Jejunum; Male; Middle Aged; Obesity; Oxalates; Postoperative Complications; Urinary Calculi

There have been 543 jejuno-ileal bypass patients screened for the presence of urinary calculi 1 to 6 years postoperatively. Of these patients 9 per cent have had 1 to 2 calculi during the followup and 3 per cent have had multiple calculi. Ninety-four per cent of the recovered calculi consisted entirely of calcium oxalate. Seven patients had a history of stones before the bypass, 6 of whom have had additional stones postoperatively. To define the conditions associated with stone formation in these patients measurements of serum and urinary oxalate concentration, urinary calcium oxalate saturation, urinary crystal size distribution, and the rates of intestinal oxalate absorption and urinary crystallization have been performed on patients who did and did not have stones postoperatively. On the basis of these studies it appears that the patients in whom stones formed differ from those in whom they did not form only in the rate of urinary crystallization and in the number of large crystal particles present in the urine. Evaluation of current therapeutic modalities in terms of the capability to correct these stone-forming characteristics and to reduce actual calculus formation reveals that the only successful regimen is that which includes an extreme reduction of oxalate ingestion.

Topics: Follow-Up Studies; Humans; Ileum; Intestinal Absorption; Jejunum; Obesity; Oxalates; Postoperative Complications; Urinary Calculi

A patient who underwent jejunoileal bypass for morbid obesity developed servere renal failure associated with hyperoxaluria and renal oxalosis. Renal function improved and oxalate excretion decreased following hemodialysis and restoration of gastrointestinal continuity.

Topics: Acute Kidney Injury; Humans; Ileum; Jejunum; Kidney Calculi; Kidney Glomerulus; Male; Microscopy, Electron; Middle Aged; Obesity; Oxalates; Postoperative Complications; Renal Dialysis

A patient with liver dysfunction following small-bowel bypass for obesity was treated successfully with intravenous hyperalimentation. The hepatic steatosis and dysfunction were most likely caused by the preferential absorption of carbohydrate in the remaining small bowel, with resulting relative protein starvation. Routine use of high-protein, low-carbohydrate diets postoperatively until weight stabilization has occurred may prevent this complication.

Topics: Adult; Biopsy; Body Weight; Dietary Carbohydrates; Dietary Proteins; Fatty Liver; Humans; Ileum; Jejunum; Liver; Liver Diseases; Male; Obesity; Oxalates; Parenteral Nutrition; Parenteral Nutrition, Total; Postoperative Complications; Protein-Energy Malnutrition

Topics: Adolescent; Adult; Anemia, Hypochromic; Avitaminosis; Cholelithiasis; Diarrhea; Female; Follow-Up Studies; Gout; Humans; Ileum; Jejunum; Kidney Calculi; Liver Diseases; Male; Middle Aged; Obesity; Oxalates; Postoperative Complications

Topics: Acidosis, Renal Tubular; Female; Humans; Hypokalemia; Ileum; Jejunum; Kidney; Middle Aged; Nephrosclerosis; Obesity; Oxalates; Postoperative Complications; Renal Aminoacidurias

Topics: Acidosis, Renal Tubular; Humans; Ileum; Jejunum; Kidney Diseases; Kidney Failure, Chronic; Nephritis, Interstitial; Obesity; Oxalates; Postoperative Complications; Renal Aminoacidurias

Jejunoileal bypass for obesity has been shown to be associated with increased hepatic triglycerides during the period of brisk weight loss. The current report describes certain metabolic changes observed in 29 patients 21 months after bypass. Significant decreases in serum cholesterol, serum triglycerides, blood sugar after a glucose load, and fasting plasma insulin levels were noted. Increased oxalate excretion and occasional episodes of hypomagnesemia occurred. Repeated clinical and laboratory observations by a medical-surgical team offer the best opportunity to evaluate this procedure.

Topics: Adolescent; Adult; Alkaline Phosphatase; Aspartate Aminotransferases; Body Weight; Evaluation Studies as Topic; Feces; Female; Glucose Tolerance Test; Humans; Ileum; Insulin; Jejunum; Kidney Calculi; Lipid Metabolism; Magnesium; Male; Middle Aged; Obesity; Oxalates; Postoperative Complications

Preoperative, operative and postoperative data from a sampling group of 435 ileal bypass patients have been tabulated and computer-analyzed. Genitourinary disorders other than stone disease have been insignificant. Patients with stones and those without stones have been compared and the significant data tabulated. The incidence of stone disease is 6 per cent. All but 1 stone consisted of calcium oxalate. Oxalate levels were normal preoperatively and elevated in 60 per cent postoperatively. The stone formers are among the heaviest members of the studied population, they have the greatest amount of ileum bypassed and the greatest amount of 1 year weight loss. Correlations between these observations and possible pathways of metabolic stone disease are made.

Topics: Body Weight; Calcium; Follow-Up Studies; Humans; Ileum; Intestine, Small; Jejunum; Obesity; Oxalates; Pyuria; Uric Acid; Urinary Calculi; Water-Electrolyte Balance

Topics: Cecum; Female; Glycolates; Humans; Ileostomy; Ileum; Intestinal Absorption; Jejunum; Kidney Calculi; Male; Obesity; Oxalates; Postoperative Complications

Five patients with jejunoileal shunt for morbid obesity in whom postshunt hyperoxaluria and recurrent urinary tract calculi developed are presented. All the stones were composed of calcium oxalate. The twenty-four hour urinary oxalic acid levels were also elevated in twenty of twenty-six patients who had had jejunoileal shunt for six months or longer. No correlation was present between urolithiasis and the degree of hyperoxaluria.

Topics: Adult; Calcium; Female; Humans; Intestine, Small; Male; Middle Aged; Obesity; Oxalates; Recurrence; Time Factors; Urinary Calculi

Anesthetic biotransformation and renal function were studied in obese adult patients (148 plus or minus 8 kg; mean plus or minus SE) anesthetized for three hours with 60 per cent nitrous oxide plus either methoxyflurane or halothane for elective jejunoileal small-bowel-bypass operations. There was no evidence of persistent renal dysfunction in any patient postoperatively, but serum osmolality was elevated 72 hours after methoxyflurane anesthesia. Urine concentrating ability was not determined. Peak serum ionic fluoride concentration was 55.8 plus or minus 5.8 muM/1 two hours after discontinuation of methoxyflurane. Urinary ionic fluoride and oxalate excretions increased postoperatively. Compared with previously reported data from nonobese patients, serum ionic fluoride concentrations in obese patients increased more rapidly during methoxyflurane anesthesia and peaked higher and sooner after discontinuation of methoxyflurane. The peak serum ionic fluoride concentration was 10.4 plus or minus 1.5 muM/1 at the conclusion of halothane anesthesia, significantly more than the corresponding value in nonobese patients. Intraoperative liver biopsies from 23 of 27 patients showed moderate to severe fatty metamorphosis. Fatty liver infiltration may have increased hepatic anesthetic uptake and exposed more methoxyflurane or halothane to hepatic microsomal enzymes. The more rapid elevation and higher peak levels of serum ionic fluoride following methoxyflurane, and to a lesser extent following halothane, may reflect increased anesthetic biotransformation in obese compared with nonobese patients. To avoid excessive serum ionic fluoride elevations the authors recommended limiting low-dose methoxyflurane anesthesia delivered to obese patients with potential fatty liver infiltration to no more than three hours.

Topics: Adjuvants, Anesthesia; Adult; Anesthesia, Inhalation; Biopsy, Needle; Biotransformation; Fatty Liver; Fluorides; Halothane; Humans; Kidney; Kidney Function Tests; Liver; Methoxyflurane; Nitrous Oxide; Obesity; Oxalates; Uric Acid

Topics: Diet; Humans; Ileum; Intestinal Absorption; Obesity; Oxalates

Of 93 patients with small bowel bypass for massive exogenous obesity, three developed calcium oxalate urinary calculi, four stones in their gallbladder, and one developed both gallstones and urinary calculi during a mean follow-up period of 17.6 plus or minus 9.0 months. The urinary oxalate excretion increased from 21.6 to 67.8 mg/24 hours (P smaller than .001); simultaneously, the urinary output decreased from 1,775 to 1,101 ml/24 hours (P smaller than .001). Postoperatively, there was a significant increase in the rate of bile salt synthesis from 1.6 to 4.9 gm/day (P smaller than .02) and in the bile sale glycine/taurine ratio from 4.6 to 6.8 (P smaller than .05). It is suggested that the postbypass increase in the biliary glycine/taurine ratio, with its consequent decrease in the zeta potential of the micelles in bile, is at least partly responsible for the increased incidence of cholelithlasis. The pathogenic basis for the increased incidence of urinary calculi is hyperoxaluria, which is probably related to an increased bile salt and glycine synthesis.

Topics: Adult; Bile; Bile Acids and Salts; Calcium; Cholelithiasis; Follow-Up Studies; Glycine; Humans; Intestine, Small; Middle Aged; Obesity; Oxalates; Postoperative Complications; Taurine; Urinary Calculi

Topics: Adult; Calcium; Humans; Ileum; Jejunum; Kidney; Kidney Failure, Chronic; Male; Nephrocalcinosis; Obesity; Oxalates; Postoperative Complications

Topics: Adult; Calcium; Cholestyramine Resin; Diarrhea; Diet; Diet Therapy; Diet, Reducing; Female; Humans; Intestine, Small; Kidney Calculi; Male; Middle Aged; Obesity; Oxalates; Postoperative Complications; Radiography; Taurine; Urinary Calculi

Topics: Adult; Calcium; Cholestyramine Resin; Diet Therapy; Humans; Ileum; Jejunum; Kidney Calculi; Male; Obesity; Oxalates; Postoperative Complications; Urography

Topics: Adolescent; Adult; Calcium; Defecation; Female; Humans; Ileum; Jejunum; Kidney Calculi; Male; Michigan; Middle Aged; Obesity; Oxalates; Serum Albumin; Uric Acid; Urography

Topics: Acute Kidney Injury; Anesthesia, General; Cholecystectomy; Electrophoresis; Fluoride Poisoning; Fluorides; Humans; Kidney; Metabolic Clearance Rate; Methoxyflurane; Obesity; Oxalates; Polyuria; Postoperative Complications

Topics: Adult; Age Factors; Aged; Body Height; Body Weight; Czechoslovakia; Factor Analysis, Statistical; Female; Humans; Kidney Calculi; Male; Middle Aged; Obesity; Oxalates; Phosphates; Sex Factors; Uric Acid

Topics: Female; Humans; Kynurenic Acid; Kynurenine; Male; Obesity; Oxalates; Pyridoxine; Starvation; Transaminases; Tryptophan; Xanthurenates