ascorbic-acid and Urinary-Calculi

Drug-induced urinary calculi, although they account for only 1-2% of urinary calculi, deserve consideration because most of them are preventable. In the drug-containing calculi resulting from the crystallization of a certain drug and its metabolites in the urine, stone analysis can identify the responsible drug. While, in the drug-induced metabolic calculi caused by interference with calcium, oxalate and purine metabolism, careful clinical inquiry is necessary to reveal involvement of a certain drug in stone formation. Better awareness of the possible drugs with lithogenic potential and close surveillance of patients on long-term treatment with these drugs are necessary. Especially, in patients with a history of urolithiaisis, prescription of lithogenic drugs deserve careful consideration.

Topics: Allopurinol; Anti-Bacterial Agents; Ascorbic Acid; Benzbromarone; Calcium; Calcium Compounds; Carbonic Anhydrase Inhibitors; Crystallization; Diuretics; Drug Combinations; Furosemide; Glucocorticoids; Humans; Magnesium Silicates; Oxalates; Protease Inhibitors; Purines; Time Factors; Triamterene; Urinary Calculi; Vitamin D

Topics: Allopurinol; Antimetabolites; Ascorbic Acid; Calcium Oxalate; Calcium, Dietary; Citric Acid; Dietary Fiber; Dietary Proteins; Drinking; Glycosaminoglycans; Humans; Magnesium; Patient Compliance; Phosphates; Recurrence; Thiazoles; Urinary Calculi

The data reviewed in this paper indicate that there is compelling direct and indirect evidence that certain dietary modifications can limit the risk for stone formation. Fluid therapy should be a front-line approach for all stone formers, because it is safe, cheap, and effective. Restricting sodium and animal-protein consumption produces changes in the urinary environment that should benefit the majority of stone formers, including a decrease in calcium and increase in citrate excretion. Minimizing the intake of processed goods limits sodium gluttony. These dietary modifications also reduce cardiovascular risks. Indiscriminant calcium restriction should be avoided, because it could accelerate stone formation and violate skeletal integrity. Oxalate restriction should be considered for calcium oxalate stone formers, especially those with hyperoxaluria. Specific recommendations for modifying the consumption of other nutrients cannot be made at this time because of the limited available information about the resultant effects. The aforementioned goals can be achieved within the context of a nutritionally balanced diet providing adequate sources of fruits and vegetables. There is a definite need for better designed studies of the nutritional effects on stone disease. This would promote a better understanding of the interplay between the genetic and environmental components of this disorder.

Topics: Ascorbic Acid; Calcium; Dietary Carbohydrates; Dietary Fats; Dietary Fiber; Dietary Proteins; Humans; Magnesium; Oxalates; Phosphorus; Potassium; Pyridoxine; Sodium, Dietary; Urinary Calculi; Vitamin D

The serum vitamin A level of the lithiasis patients was found to be low, although vitamin A intake was not different from control subjects. Vitamin C level in blood was not significantly different in the patients as compared with control subjects. The control subjects and urolithiasis patients were also subjected to the oral supplementation of L-tryptophan and glycine. It was observed that neither oxalate nor xanthurenic acid increased in urine after loading. It was concluded that vitamin B6 deficiency does not exist in these cases.

Topics: Adult; Ascorbic Acid; Glycine; Humans; Pyridoxine; Tryptophan; Urinary Calculi; Vitamin A; Vitamins

Although there is much concern about the relationship between vitamin C consumption and oxalate or uric acid lithiasis in the urinary tract, there is no controlled clinical study that demonstrates this occurrence. Equal concern should be accorded the other nutritional links to urinary lithiasis, since it is very unlikely that vitamin C or any one of the other factors is ever the sole cause of a kidney stone. The rare persons who, because of an altered metabolism, convert much of the ingested vitamin C into oxalic acid constitute the only high-risk category. If the other known nutritional variables were also investigated in these metabolically crippled persons, it might be possible to reduce or eliminate their risk from the intake of vitamin C.

Topics: Adult; Ascorbic Acid; Calcium Oxalate; Diet; Humans; Magnesium; Male; Nutritional Physiological Phenomena; Pyridoxine; Risk; Uric Acid; Urinary Calculi

Topics: Ascorbic Acid; Celiac Disease; Citrates; Colitis, Ulcerative; Crohn Disease; Dietary Fats; Gastrointestinal Diseases; Humans; Hyperparathyroidism; Ileostomy; Intestine, Small; Liver Diseases; Malabsorption Syndromes; Oxalates; Solubility; Urinary Calculi

Topics: Animals; Ascorbic Acid; Calcium; Chemical Phenomena; Chemistry; Child, Preschool; Diet; Glycine; Glycolates; Humans; Hydrogen-Ion Concentration; Isoenzymes; L-Lactate Dehydrogenase; Male; Metabolism, Inborn Errors; Mitochondria, Liver; Nutritional Physiological Phenomena; Oxalates; Rats; Solubility; Urinary Calculi

Topics: Ascorbic Acid; Bone and Bones; Calcium; Cell Membrane Permeability; Erythrocytes; Feces; Glycine; Humans; Intestinal Absorption; Intestinal Mucosa; Kidney; Kidney Diseases; Kidney Function Tests; Liver; Metabolism, Inborn Errors; Microsomes; Mitochondria; Muscles; Oxalates; Plants, Edible; Urinary Calculi

Ascorbic acid is frequently administered intravenously by alternative health practitioners and, occasionally, by mainstream physicians. Intravenous administration can greatly increase the amount of ascorbic acid that reaches the circulation, potentially increasing the risk of oxalate crystallization in the urinary space. To investigate this possibility, we developed gas chromatography mass spectrometry methodology and sampling and storage procedures for oxalic acid analysis without interference from ascorbic acid and measured urinary oxalic acid excretion in people administered intravenous ascorbic acid in doses ranging from 0.2 to 1.5 g/kg body weight. In vitro oxidation of ascorbic acid to oxalic acid did not occur when urine samples were brought immediately to pH less than 2 and stored at -30 degrees C within 6 hours. Even very high ascorbic acid concentrations did not interfere with the analysis when oxalic acid extraction was carried out at pH 1. As measured during and over the 6 hours after ascorbic acid infusions, urinary oxalic acid excretion increased with increasing doses, reaching approximately 80 mg at a dose of approximately 100 g. We conclude that, when studied using correct procedures for sample handling, storage, and analysis, less than 0.5% of a very large intravenous dose of ascorbic acid is recovered as urinary oxalic acid in people with normal renal function.

Topics: Adult; Aged; Antioxidants; Ascorbic Acid; Calcium Oxalate; Female; Humans; Hyperoxaluria; Injections, Intravenous; Male; Middle Aged; Neoplasms; Oxalic Acid; Urinary Calculi

Ascorbic acid (AA) has been implicated as a risk factor for calcium oxalate stones due to its conversion to oxalate and potential acidifying properties. We evaluated the effect of AA consumption on urinary saturation of calcium oxalate (CaOx) and urinary pH.. A total of 12 normal subjects (NS) and 12 CaOx stone formers (SF) underwent 2, 6-day phases of study while maintained on a controlled metabolic diet. In each phase subjects ingested 1 gm AA or an identical appearing placebo twice daily. On the last 2 days of each phase 2, 24-hour urine collections were analyzed for pH and stone risk factors, and blood specimens were submitted for serum chemistry studies.. No difference in urinary pH was found between placebo and AA phases in NS (6.02 versus 6.02) and SF (6.0 versus 6.0). However, urinary oxalate was statistically significantly higher in the AA versus placebo phase for NS (34.7 versus 28.5 mg, p = 0.008) and SF (41.0 versus 30.5 mg, p <0.001). Likewise, the CaOx relative saturation ratio was significantly higher in the AA versus placebo phase for both groups.. Ingestion of 2 gm AA daily results in no change in urinary pH but a moderate though statistically significant increase in urinary oxalate in NS (20%) and SF (33%). Stone formers respond no differently to AA than normal subjects. We recommend limiting AA use to less than 2 gm daily in CaOx stone formers.

Topics: Adult; Ascorbic Acid; Calcium Oxalate; Cross-Over Studies; Dietary Supplements; Double-Blind Method; Female; Humans; Hydrogen-Ion Concentration; Male; Risk Factors; Urinary Calculi

The role of ascorbic acid (ASC) in the pathophysiology of renal calcium stones is not clear. We evaluated ASC in blood and urine of fasting male patients with idiopathic calcium urolithiasis (ICU) and healthy volunteers. Using smaller subgroups, we also evaluated their response to exogenous ASC [either intravenous or oral ASC (5 mg/kg bodyweight)] administered together with an oxalate-free test meal. The influence of ASC on calcium oxalate crystallization, the morphology of crystals at urinary pH 5, 6 and 7, and the effect of increasing duration of urine incubation on urinary oxalate at these pHs, without and with addition of ASC, were studied too. In normo- and hypercalciuric ICU, blood and urinary ASC from fasting patients remained unchanged, but the slope of the regression line of urinary ASC versus urinary oxalate was steeper than in the controls; the plasma ASC half-life did not differ between controls, normo- and hypercalciuric ICU; the ASC-supplemented meal caused an increase in the integrated plasma oxalate in the normocalciuric subgroup versus controls. In normo- and hypercalciuric ICU urinary oxalate, the oxalate/glycolate ratio, and calcium oxalate supersaturation were increased, but urinary glycolate was unchanged. In the controls, oral ASC did not affect calcium oxalate crystallization, while in ICU, ASC inhibited crystal growth. In control urine calcium oxalate dihydrate and calcium oxalate monohydrate develops, while in ICU urine only the former crystal type develops. In vitro oxalate neoformation from ASC did not occur. It was concluded that (1) under normal conditions an abettor role of ASC for renal stones is not recognizable, (2) in ICU, urinary oxalate excess unrelated to degradation of exogenous ASC is exhibited, and that this is most likely unrelated to an initial increase in oxalate biosynthesis, and (3) ASC appears to modulate directly calcium oxalate crystallization in ICU, although the true mode of action is still not known.

Topics: Administration, Oral; Adolescent; Adult; Aged; Antioxidants; Ascorbic Acid; Calcium; Calcium Oxalate; Crystallization; Fasting; Humans; Injections, Intravenous; Male; Recurrence; Urinary Calculi

We reviewed the clinical data relating to the efficacy and safety of pharmacologic doses of ascorbic acid in the prevention and treatment of the common cold. Although one study tentatively supports the hypothesis that such doses of ascorbic acid may be efficacious, a second study by the same group did not confirm the significant findings, and no clear, reproducible pattern of efficacy has emerged from the review of all the evidence. Similarly, there is currently little adequate evidence on either the presence or the absence of serious adverse reactions to such doses of ascorbic acid, although many such reactions have been hypothesized. The unrestricted use of ascorbic acid for these purposes cannot be advocated on the basis of the evidence currently available.

Topics: Administration, Oral; Animals; Ascorbic Acid; Clinical Trials as Topic; Common Cold; Digestive System; Drug Interactions; Female; Fetus; Flavonoids; Guinea Pigs; Humans; Hyperglycemia; Injections, Intravenous; Injections, Subcutaneous; Male; Maternal-Fetal Exchange; Placebos; Pregnancy; Rats; Time Factors; Urinary Calculi

Topics: Ascorbic Acid; Benzothiadiazines; Calcium Oxalate; Dietary Supplements; Diuretics; Humans; Sodium Chloride Symporter Inhibitors; Urinary Calculi

Renal injury is considered as one of the prerequisites for calcium oxalate retention. In order to determine the role of lipid peroxidation related effects for hyperoxaluria, we evaluated the alterations in lipid peroxidation, antioxidants and oxalate synthesizing enzymes in lithogenic rats with response to vitamin E + selenium treatment. In kidney of lithogenic rats, the level of lipid peroxidation and the activities of oxalate synthesizing enzymes were found to be increased whereas the levels/activities of non-enzymatic and enzymatic antioxidants were found to be decreased. The urinary excretion of both oxalate and calcium were significantly elevated. Supplementation of lithogenic rats with vitamin E + selenium decreased the levels of lipid peroxides and the activities of oxalate synthesizing enzymes like glycolic acid oxidase (GAO), lactate dehydrogenase (LDH), xanthine oxidase (XO) with a concomitant increase in the activities of enzymatic antioxidants like superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glucose-6-phosphate dehydrogenase (G6PDH) and increased levels of non-enzymatic antioxidants like ascorbic acid, alpha-tocopherol and reduced glutathione (GSH). The urinary excretion of oxalate and calcium were normalized. The antioxidants vitamin E + selenium thereby protected from hyperoxaluria.

Topics: Alcohol Oxidoreductases; Animals; Antioxidants; Ascorbic Acid; Calcium Oxalate; Catalase; Dietary Supplements; Glucosephosphate Dehydrogenase; Glutathione; Glutathione Peroxidase; Hyperoxaluria; Kidney; L-Lactate Dehydrogenase; Lipid Peroxidation; Liver; Male; Rats; Rats, Wistar; Selenium; Superoxide Dismutase; Urinary Calculi; Vitamin E; Xanthine Oxidase

To study the role of dietary and nutritional factors in the etiology of urolithiasis.. Two hundred and fourty-one pairs of urolithiasis patients and controls were selected, and matched on age and sex, and without having urinary, endocrine, metabolic, or other related diseases. Subjects were given with a standardized semi-quantitative questionnaire to inquire their demographic features and diet information. Data were analyzed according to their respective property. Conditional logistic regression were used to compute odds ratio and 95% confidence interval.. The following variables were found to have significant in single factor logistic regression analysis: do not fond of drinking water [OR(no:yes) = 1.914 (95% CI: 1.272 - 2.881)]; drinking less purified water [OR(once:more) = 0.771 (95% CI: 0.614 - 0.967)]; drinking less liquid [OR(one cup more) = 0.273 (95% CI: 0.076 - 0.978)]; eating salted food [OR(highest:common) = 3.382 (95% CI: 2.133 - 5.362), OR(higher:common) = 1.435 (95% CI: 1.252 - 1.645)]; fond of sweet food [OR(most:no) = 4.509 (95% CI: 2.457 - 8.277), OR(more:no) = 1.562 (95% CI: 1.305 - 1.870)]; intake of animal oil [OR(yes:no) = 2.222 (95% CI: 1.012 - 4.880)]; over intake of protein, fat and phosphorus; less intake of carbohydrate, dietary fibre and vitamin C.. Results indicated that dietary and nutritional factors were important risk factors to the etiology of urinary calculi.

Topics: Ascorbic Acid; Case-Control Studies; Diet; Drinking; Humans; Logistic Models; Nutritional Physiological Phenomena; Risk Factors; Urinary Calculi

To examine the relationship between 12 macro- and micro-nutrients and the risk of recurrent calcium stone formation by comparing the diets of a large outpatient clinic-based group of patients who had formed calcium-based urinary tract calculi with that of a population-based control group matched for age, gender and body mass index.. The dietary intake of 500 patients (cases) randomly selected from the adult population attending an outpatient renal-stone clinic and being evaluated and/or treated for biochemically or radiologically diagnosed calcium-based upper urinary tract calculi were compared with those of 500 control subjects selected to match for age, sex and body mass index from a stratified probability sample of 2212 adults (not institutionalized) living in the same geographical area.. Comparing the mean nutritional intakes showed a statistically higher consumption of energy, carbohydrates, sodium, fibre, vitamin C, fat and folic acid among cases than in controls. The intake of calcium, alcohol and vitamin A was significantly higher among the controls. There were no significant differences in the intake of protein, niacin or iron. The results of these comparisons varied when the groups were stratified by sex, age and body mass index.. Dietary risk factors for calcium-based urinary tract calculi are many and complex, and a detailed consideration of sex, age and body mass index is important in interpreting such data. While it is difficult to draw firm conclusions about causes and effects of individual nutrients from the available data, this study indicates a possibly more important role for dietary fat in stone formation than has been previously recognized. This relationship needs to be further explored in relation to urinary risk factors, as it may be possible to advise patients to reduce dietary fat as a prophylactic measure for stone formation. As dietary fat has been associated with cardiovascular diseases and possibly cancer, an overall recommendation to these patients for a low dietary fat intake may be easier to follow.

Topics: Adult; Aged; Alcohol Drinking; Ascorbic Acid; Calcium, Dietary; Case-Control Studies; Dietary Carbohydrates; Dietary Fiber; Feeding Behavior; Female; Humans; Male; Middle Aged; Sodium, Dietary; Urinary Calculi; Vitamin A

Ascorbate breakdown reportedly accounts for 30% to 55% of urinary oxalate excreted. Three potential degradation routes can be postulated: bowel, endogenous, and urinary. Because the pH of normal urine ranges from 4.5 to 8.0, the urinary oxalate concentration in the presence of ascorbate may be influenced by urinary pH and environment, so we studied ascorbate conversion to oxalate in standard buffer solution and in urine. About 10% of infection stones associated with Proteus mirabilis are reportedly composed of calcium oxalate, and their pathogenesis is not well explained. Therefore, we studied whether a pH change induced by P. mirabilis contributes to ascorbate conversion to oxalate in vitro.. Oxalate production from ascorbate increased as a function of pH (7.0-10.0) and incubation time (30 minutes-24 hours) in standard and urine specimens. Two-hour exposure to pH 10 in a urinary milieu containing approximately 3 mM ascorbate converted approximately 40% of the ascorbate to oxalate, whereas 24-hour exposure to pH 8 in a urinary milieu that was approximately 3 mM ascorbate converted approximately 20% of the ascorbate to oxalate. The pH in Proteus cultures increased to 9.0 at 24 hours of culture. The ascorbate concentration in the culture medium significantly decreased at 12 hours and 24 hours, and the oxalate concentration increased significantly at 24 hours.. Urinary ascorbate, if present at a high concentration in association with Proteus mirabilis infection, appears to be locally degraded to oxalate, potentially leading to calcium oxalate deposition on infection stones.

Topics: Ascorbic Acid; Humans; Hydrogen-Ion Concentration; Oxalates; Proteus mirabilis; Temperature; Time Factors; Urinary Calculi

In idiopathic recurrent calcium urolithiasis (RCU) the state of insulin and carbohydrate metabolism, and relationships to minerals such as phosphate, are insufficiently understood. Therefore, in two groups of males with RCU (n = 30) and healthy controls (n = 8) the response to an oral carbohydrate- and calcium-rich test meal was studied with respect to glucose, insulin, and C-peptide in peripheral venous blood (taken before and up to 180 min post-load), and phosphate and glucose in fasting and post-load urine. In one RCU group (n = 16) the meal was supplemented with ascorbic acid (ASC; 5 mg/kg body weight). The mean age (RCU 29, RCU + ASC 30, controls 27 years) and mean body mass index [RCU 24.4, RCU + ASC 25.0, controls 24.0 kg/m2] were similar. Insulin resistance (synonymous sensitivity of peripheral organs to insulin) was calculated from insulin serum concentration, as was also integrated insulin, C-peptide, and glucose. Untreated stone patients (RCU) developed hyperinsulinaemia between 60 and 120 min post-load, increased integrated insulin, and insulin resistance (P < or = 0.05 vs controls), whereas the rise of C-peptide and glycaemia (absolute and integrated values) was only of borderline significance. Fasting phosphaturia was low in both RCU subgroups vs controls; however, phosphaturia in untreated RCU rose in response to the meal, contrasting sharply with a decrease in controls. ASC supplementation of the meal (in the RCU + ASC subgroup) normalized insulin, failed to normalize post-load phosphaturia, but reduced post-load glucosuria and urinary pH significantly (mean pH values 5.55 vs 5.93 in untreated RCU, controls 5.50). Postprandial urinary oxalate, calcium, protein, and supersaturation products were not changed. The postprandial changes in phosphaturia and insulin sensitivity were inversely correlated (n = 38, r = -0.44, P = 0.007). It was concluded that in younger RCU males: (1) postprandial hyperinsulinaemia, the failure to reduce phosphaturia and - within limits - glucosuria, appropriately, as well as poor urine acidification are important features of the metabolism; (2) these phenomena are probably caused by insulin resistance of organs, the kidney included; and (3) the addition of a supraphysiological dose of ASC to a meal, the subsequent abolition of hyperinsulinaemia, and the restoration of normal urine acidification suggest that this antioxidant is capable of counteracting some pre-existing basic abnormality of cell metabolism in RCU.

Topics: Adult; Ascorbic Acid; Blood Glucose; C-Peptide; Fasting; Glucose; Humans; Hyperinsulinism; Insulin; Insulin Resistance; Male; Phosphates; Postprandial Period; Time Factors; Urinary Calculi; Urine

A simple, reliable high-performance liquid chromatographic method was developed to measure ascorbic acid (ASC), with ultraviolet detection (250 nm), in human plasma and urine. Immediately following blood withdrawal, the heparinized plasma samples were deproteinized with 10% m-phosphoric acid, while the freshly voided urine samples were diluted with m-phosphoric acid. ASC was separated on a reversed-phase column by elution with 0.1 M KH2PO4 adjusted to pH 2.35. In urine, after reduction of dehydroascorbic acid to ASC, total ASC was measured using the same mobile phase. The method was sensitive down to 0.1 and 0.4 mg ASC per litre of urine and plasma, respectively. In patients with idiopathic calcium urolithiasis, both plasma and urinary ASC were within the range observed in age-matched controls.

Topics: Adult; Aged; Ascorbic Acid; Calcium; Chromatography, High Pressure Liquid; Female; Humans; Male; Middle Aged; Phosphoric Acids; Quality Control; Reference Values; Sensitivity and Specificity; Urinary Calculi

Topics: Ascorbic Acid; Cystine; Cystinuria; Humans; Urinary Calculi

Topics: Ascorbic Acid; Calcium Oxalate; Humans; Urinary Calculi

Urinary calculi found in 4 patients on chronic hemodialysis or continuous ambulatory peritoneal dialysis (CAPD) were identified as protein calculi by infrared spectroscopic analysis. Positive Congo red staining and immunological assessment revealed that the calculi were composed of amyloid protein derived from beta 2-microglobulin. A comparison of the patients who excreted calculi with 10 patients on chronic dialysis without urinary calculi showed no significant differences in the urinary and serum levels of beta 2-microglobulin. The mechanism of amyloid calculus formation may involve factors independent of the concentration of beta 2-microglobulin in urine or serum. Urinary calculi found in patients on chronic hemodialysis or CAPD were composed of amyloid protein derived from beta 2-microglobulin.

Topics: Amyloid; Ascorbic Acid; beta 2-Microglobulin; Humans; Immunodiffusion; Kidney Failure, Chronic; Renal Dialysis; Spectrophotometry, Infrared; Uric Acid; Urinary Calculi

A semiquantitative method is presented for the determination of cysteine in urine, based on the formation of a red cysteine/nitroprusside salt. The method is suitable as a rapid test for checking the progress of ascorbic acid therapy of cystinuria and cystine urolithiasis. It guarantees acceptable reproducibility of values and can be easily carried out in any clinical chemical laboratory. With the K2CO3/nitroprusside test described and an additional colorimetric determination of cystine (CN-/nitroprusside), a separate semiquantitative differentiation of cysteine and cystine in fresh (!) urine is possible.

Topics: Ascorbic Acid; Cysteine; Cystinuria; Humans; Monitoring, Physiologic; Urinary Calculi

Primary bladder stone is a common pediatric surgical problem in developing countries. Many theories are prevalent. The stone matrix theory is based on increased excretion of its precursor, the uromucoid (the urinary mucoprotein). Uromucoid, studied in urine and stones by the electroimmunodiffusion technique in 49 cases with controls, showed significantly increased excretion in stone cases. Family income and serum protein were the only important influencing factors (negative). Causal relationship between uromucoid excretion, stone matrix, and pediatric bladder stones is discussed. Methylene blue decreased uromucoid excretion but not magnesium oxide, vitamin C or B6 (four common therapeutic drugs for prevention/dissolution of urolithiasis).

Topics: Ascorbic Acid; Calculi; Child; Child, Preschool; Female; Humans; Infant; Magnesium Oxide; Male; Methylene Blue; Mucoproteins; Pyridoxine; Urinary Calculi; Uromodulin

In this paper a method of semiquantitative cysteine determination is presented, which is based on the formation of a red cysteine-Na-nitroprusside salt. The method is a suitable rapid test for checking the process of ascorbic acid therapy in cystinuria and cystine urolithiasis patients. It guarantees acceptable reproducibility of values and can be easily carried out in every clinicochemical laboratory. With the K2CO3/nitroprusside test described and an additional cystine rapid test (Ni2+/S2O4(2-) tablet reagency) a separate semiquantitative differentiation of cysteine and cystine in fresh (!) urine is possible.

Topics: Ascorbic Acid; Carbonates; Cysteine; Cystinuria; Ferricyanides; Humans; Nitroprusside; Potassium; Urinary Calculi

Topics: Adult; Ascorbic Acid; Female; Humans; Intestinal Absorption; Intestinal Diseases; Male; Middle Aged; Oxalates; Urinary Calculi

Studies of recurrent stone formers indicated that they have significantly increased urinary oxalate and decreased ascorbate excretions. Results of oral and intravenous administration of ascorbate indicate an enhanced production of oxalate from ascorbate in recurrent calcium stone formers as compared with normal persons and that most of this oxalate is generated in the gut.

Topics: Adult; Ascorbic Acid; Calcium Oxalate; Female; Humans; Kidney Calculi; Male; Middle Aged; Oxalates; Time Factors; Urinary Calculi

Topics: Ascorbic Acid; Humans; Urinary Calculi

Long-term results of ascorbic acid monotherapy in four young patients with cystine stone complaints are reported. The therapeutic program is based on the descriptions by Asper and Schmucki, who publicized the method for the first time in 1979. Clinical course observations, renal function checks as well as the excretion of cystine, uric acid and oxalic acid during ascorbic acid therapy of our patient pool will be discussed. Clinical observations made to date indicate that ascorbic acid therapy is a practical, inexpensive prophylaxis for cystine stone patients that is virtually free of side effects.

Topics: Adolescent; Adult; Ascorbic Acid; Child; Cystinuria; Humans; Male; Urinary Calculi

Base-line values for the excretion of urea N, amine N, creatinine, uric acid and cysteine were measured in three consecutive 24-h urine collections from 16 healthy volunteers. The subjects then took 1 g ascorbic acid three times a day after meals for 7 days. Twenty-four hour urine samples were collected on the 1st, 3rd, 5th and 7th days of the study. Where possible, a further 24-h sample was collected a minimum of 10 d after the end of the study. Administration of 3 g/d of ascorbic acid had no effect on urine volume, pH or the excretion of urea, amino N or creatinine. It caused a transient increase in uric acid excretion but an immediate and sustained increase in the excretion of cysteine. This study provides no evidence for an effect of high doses of ascorbic acid on urinary stone formation but does suggest competition for important co-factors in the metabolism of drugs.

Topics: Adult; Amines; Ascorbic Acid; Creatinine; Cysteine; Humans; Nitrogen; Urea; Uric Acid; Urinary Calculi

Topics: Administration, Oral; Ascorbic Acid; Dose-Response Relationship, Drug; Humans; Oxalates; Urinary Calculi

Topics: Ascorbic Acid; Citrates; Enzyme Inhibitors; Humans; Ion Exchange Resins; Risk; Urease; Urinary Calculi; Urine; Urodynamics

We report on our experience with 9 cystine-lithiasis patients who were treated with large doses of ascorbic acid (5 g/day) for periods ranging from 6-27 months. We observed recidive lithogenesis in only 3 patients during this time. The influence of ascorbic acid on the excretion of cystine and oxalate in the urine is discussed. A lack of side effects and the significantly lower frequency of recidivation justify the further use of ascorbic as an alternative medication in cystine lithiasis.

Topics: Adult; Ascorbic Acid; Cystine; Cystinuria; Dose-Response Relationship, Drug; Female; Humans; Kidney Calculi; Male; Middle Aged; Oxalates; Oxalic Acid; Recurrence; Urinary Bladder Calculi; Urinary Calculi

Topics: Ascorbic Acid; Dose-Response Relationship, Drug; Humans; Oxalates; Oxalic Acid; Urinary Calculi

The annual incidence of urolithiasis in the population is at least 0.1%. In rural areas, there are remarkably less actual stone formers than in urban districts, and also vegetarians show less stone diseases. Calcium carbonate as a urinary calculus compound is not in the strict sense impossible, but often an artifact. About 10% of homozygotic cystinuria patients never suffer an actual stone disease.. It is obvious that for stone formation urinary supersaturation alone is not sufficient. Besides the well-known inhibitors like citrate, magnesium and pyrophosphate there have to be other important urinary constituents. Risk factors are high protein or glucose intakes and, in general, hyperalimentation, simply because any food has to be deplenished somehow and increases the urine concentration. A special cause may be found in alterations of the renal tubuli. Diagnostic: For the quite difficult oxalate analysis, an enzymatic test is commercially available. Up to now, the most important analytical task in urolithiasis is still the correct analysis of urinary calculi. Qualitative chemical analysis shows up to 50% erroneous results, leading to false therapies. To determine the calculus compounds the best appropriate method is by far the X-ray diffraction analysis.. The results with adsorption medicines are contradictory. Satisfactory therapies are given for uricosuria with allopurinol and for oxaluria with pyridoxine. A new therapy for cystinuria may be the combined application of ascorbic acid and sodium hydrogen carbonate.

Topics: Allopurinol; Ascorbic Acid; Carbonates; Diet; Humans; Pyridoxine; Risk; Urinary Calculi

With a new enzymatic method, the dietary influence of oxalate, glycine, protein, and ascorbic acid on serum and urinary oxalate has been examined. Healthy and oxalate stone-forming subjects were compared. Two doses of sodium oxalate (130 and 400 mg daily) were administered. The high dose induced significant hyperoxaluria. No changes of serum oxalate were seen. Neither glycine (4.5 g daily) nor protein (50 g daily, 50% animal protein) had any effect on serum or urinary oxalate. Urinary oxalate excretion did not increase upon ingestion of large amounts of ascorbic acid (1--6 g daily), but serum oxalate levels were significantly elevated. The value of severe dietary restrictions concerning the compounds examined here seems to be questionable, as a significant increase of urinary oxalate excretion is lacking.

Topics: Ascorbic Acid; Diet; Dietary Proteins; Glycine; Humans; Male; Oxalates; Urinary Calculi

Urinary calculi composed of calcium oxalate were produced in male hooded Wistar rats fed a vitamin B6 deficient diet over 16 weeks. This basic diet was modified by doubling the phosphate content or loading with vitamin C or D3 in three treatment groups. The number of rats developing oxalate stones was not altered by the addition of vitamin D3 or phosphate, but there was a significant increase in total weight of stone formed and histological evidence of extensive renal damage in rats on the high vitamin D3 diet. The addition of vitamin C to the vitamin B6 deficient rats resulted in a reduction in the number of rats with uroliths and a fall in urinary oxalate excretion, while similarly loaded vitamin B6 supplemented controls were free of oxalate calculi. It is concluded that the oxalate urolithiasis induced by vitamin B6 deficiency was exacerbated by added vitamin D3 and reduced by vitamin C.

Topics: Animals; Ascorbic Acid; Body Weight; Calcium Oxalate; Cholecalciferol; Diet; Kidney; Male; Phosphates; Pyridoxine; Rats; Urinary Calculi; Vitamin B 6 Deficiency

Topics: Ascorbic Acid; Humans; Oxalates; Risk; Urinary Calculi

The diurnal urinary oxalate excretion has been determined in 11 patients with urolithiasis and in 7 normal subjects. Increased excretion following meals was observed. The variation from hour to hour was most pronounced in the stone patient group. The relation between oxalate concentration and urinary volume was found to follow a biphasic exponential course. Pyridoxine administration increased oxalate excretion in 9 out of 12 subjects and decreased the excretion in 3 subjects. Ascorbate administration increased oxalate excretion in all 7 subjects studied.

Topics: Ascorbic Acid; Circadian Rhythm; Humans; Oxalates; Pyridoxine; Urinary Calculi

Topics: Adult; Ascorbic Acid; Humans; Male; Oxalates; Stimulation, Chemical; Urinary Calculi

Urinary excretion of 4-pyridoxic acid and oxalic acid was investigated in 75 patients with urinary calculi and in 50 normal subjects on regular diet. Mean excretion of 4-pyridoxic acid was 0.85 and 0.90 mg per day, respectively, and mean excretion of oxalic acid was 27.5 and 28.0 mg per day, respectively. Statistically there was no difference between the two groups in 4-pyridoxic acid excretion or in oxalic acid excretion. There was a weak positive correlation between the urinary excretion of 4-pyridoxic acid and oxalic acid. Patients who were on ascorbic acid supplementation during the urine collection period excreted increased amounts of oxalic acid. It was concluded from this investigation that most patients with urinary calculi had 4-pyridoxic acid excretion and oxalic acid excretion within normal limits. Low 4-pyridoxic acid values were not combined with high excretion values of oxalic acid, and the nutritional state of vitamin B6 in patients with urinary calculi was assumed to be satisfactory in order to control the endogenous oxalic acid production. The significance of high excretion values of 4-pyridoxic acid and oxalic acid is discussed.

Topics: Ascorbic Acid; Female; Humans; Isonicotinic Acids; Male; Oxalates; Pyridoxic Acid; Pyridoxine; Urinary Calculi

Topics: Animal Feed; Animal Nutritional Physiological Phenomena; Animals; Ascorbic Acid; Cat Diseases; Cats; Dietary Proteins; Meat; Nutrition Disorders; Nutritional Requirements; Osteogenesis Imperfecta; Plant Proteins, Dietary; Riboflavin Deficiency; Rickets; Thiamine Deficiency; Urinary Calculi; Vitamin A; Vitamin A Deficiency; Vitamin B 6 Deficiency; Vitamin D Deficiency; Vitamin E Deficiency

Topics: Adult; Aged; Aneurysm; Ascorbic Acid; Female; Glomerular Filtration Rate; Humans; Hydronephrosis; Hypertension, Renal; Iodine Radioisotopes; Iodohippuric Acid; Isotope Labeling; Kidney; Kidney Calculi; Kidney Diseases, Cystic; Kidney Neoplasms; Male; Middle Aged; Pyelonephritis; Quality Control; Radioisotope Renography; Renal Artery; Renal Artery Obstruction; Technetium; Urinary Calculi

Topics: Adult; Ascorbic Acid; Humans; Male; Radiography; Time Factors; Urinary Calculi

Topics: Allopurinol; Aluminum; Ammonium Chloride; Ascorbic Acid; Citrates; Glycine; Humans; Magnesium; Penicillamine; Phosphates; Pyridoxine; Recurrence; Urinary Calculi

Topics: Academies and Institutes; Adult; Ascorbic Acid; Child; Child, Preschool; Common Cold; Evaluation Studies as Topic; Female; Fetus; Humans; Hydrogen-Ion Concentration; Infant; Infant, Newborn; Pediatrics; Pregnancy; Urinary Calculi; Urinary Tract Infections; Urine

Topics: Ascorbic Acid; Cervix Mucus; Contraception; Female; Humans; Infertility, Female; Pregnancy; Urinary Calculi

Topics: Acidosis; Ammonium Chloride; Ascorbic Acid; Betaine; Evaluation Studies as Topic; Humans; Hydrochloric Acid; Hydrogen-Ion Concentration; Lysine; Pepsin A; Urinary Calculi; Urinary Tract Infections; Urine

Topics: Animals; Ascorbic Acid; Chickens; Diabetes Mellitus; False Positive Reactions; Female; Fetal Death; Fetus; Glycosuria; Guinea Pigs; Humans; Oxalates; Phosphates; Pregnancy; Rats; Urinary Calculi

Topics: Animals; Ascorbic Acid; Humans; In Vitro Techniques; Oxalates; Rats; Urinary Calculi; Urine

Topics: Ascorbic Acid; Child; Child, Preschool; Glycine; Glyoxylates; Humans; In Vitro Techniques; Metabolism, Inborn Errors; Oxalates; Urinary Calculi; Urine

Topics: Anticoagulants; Ascorbic Acid; Breast Feeding; Calcium; Calcium, Dietary; Common Cold; Dental Caries; Female; Fluorides; Humans; Infections; Iodine; Lactation; Myocardial Infarction; Penicillins; Pregnancy; Preventive Medicine; Silver Nitrate; Sulfonamides; Urinary Calculi