Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0451641 (urolithiasis)
 3,973 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To evaluate underlying causes of calcium oxalate urolithiasis, 24-hour excretion of urine metabolites was measured in 6 Miniature Schnauzers that formed calcium oxalate (CaOx) uroliths during periods when they were fed a standard diet and during periods when food was withheld. Serum concentrations of parathyroid hormone and 1,25-dihydroxyvitamin D also were evaluated. Serum calcium concentrations were normal in all 6 affected Miniature Schnauzers; however, during diet consumption, mean 24-hour urinary excretion of calcium was significantly (P = 0.025) higher than calcium excretion when food was withheld. In 1 dog, urinary calcium excretion was lower during the period of food consumption, compared with the period when food was withheld. Compared with clinically normal Beagles, Miniature Schnauzers that formed CaOx uroliths excreted significantly greater quantities of calcium when food was consumed (P = 0.0004) and when food was withheld (P = 0.001). Miniature Schnauzers that formed CaOx uroliths excreted significantly less oxalate than clinically normal Beagles during fed (P = 0.028) and nonfed (P = 0.004) conditions. Affected Miniature Schnauzers also excreted abnormally high quantities of uric acid. Excretion of citrate was not different between Miniature Schnauzers with CaOx urolithiasis and clinically normal Beagles. In 5 of 6 Miniature Schnauzers with CaOx urolithiasis, concentrations of serum parathyroid hormone were similar to values from age- and gender-matched Miniature Schnauzers without uroliths. The concentration of serum parathyroid hormone in 1 dog was greater than 4 times the mean concentration of clinically normal Miniature Schnauzers. Mean serum concentrations of 1,25-dihydroxyvitamin D in Miniature Schnauzers with calcium oxalate urolithiasis were similar to concentrations of clinically normal Miniature Schnauzers.
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PMID:Evaluation of urine and serum metabolites in miniature schnauzers with calcium oxalate urolithiasis. 176 76

Urinary concentrations of certain biochemical constituents that play an active role in stone formation were determined in 2 h urine collections in healthy men and women (at four phases of the estrous cycle) to elucidate the sex difference in the incidence of urolithiasis. The excretion of the lithogenic substance, calcium, was higher in men than in women during phase I (p less than 0.01) and phase II (p less than 0.05) of the estrous cycle. Oxalate excretion was marginally elevated in men compared to women during each phase. Urinary citrate was lower in men compared to women during each phase (p less than 0.05). Uric acid excretion was lower (p less than 0.05) in men compared with phase I and phase III in women. Estrous phase-related alterations were also observed in the excretion of calcium and citrate in women. The data suggest that low concentrations of calcium and oxalate with an elevated citrate excretion might be responsible for the reduced risk of stone disease in women compared to men.
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PMID:Urinary composition in men and women and the risk of urolithiasis. 177 89

The main risk factors for calcium urolithiasis that are clinically detectable are low diuresis, hypercalciuria, hyperruricuria, alkaline urinary pH, hyperoxaluria, hypomagnesuria, hypocitraturia. They should be evaluated, all the more precisely that the disease is active, under both the urological and metabolic points of view, using 24 hour urine collection made at home on a free diet with a dietary record. In the majority of the cases the calcic urolithiasis is idiopathic, i.e. not related to a cause of secondary hypercalciuria like primary hyperparathyroidism, or to a hyperroxaluria either primary or of digestive or toxic origin. Its treatment if mainly dietary with high fluid intake (diuresis greater than 2 1/24 h), normoclacic diet (800-1000h mh/24 h) with meat but not dairy product restriction, oxalate salts, carbohydrate and alcohol restriction. These dietary recommendations should be controlled by measuring the above cited parameters in the 24 hour urine samples and by measuring urea excretion which should not exceed 0.33 g/kg of body weight. When diet fails, drugs may be added mainly allopurinol, thiazides and potassium citrate.
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PMID:[Physiopathology, exploration and treatment of calcium lithiasis]. 178 95

Of 1,211 patients with urolithiasis treated at this institution over a nine years period, there were 77 (6.4%) pediatric cases. The commonest age group was 6-10 years (55.8%). Male:female ratio was 7.6:1. Hindus constituted 72.7% of the patients. There was no significant seasonal variation. The commonest site was urinary bladder (67.5%). The upper: lower urinary tract stone ratio was 1:2.85. Majority belonged to the lower-middle or poor income groups having a cereal based diet with minimal or poor protein intake. The common constituents of stones were calcium (98.7%), oxalate (87%), phosphate (84.4%) and uric acid (76.6%). Of all these, uric acid had the richest concentration (grade of ++ or more) in 93.2%. Only 4 stones (5.2%) were "pure": calcium oxalate--3 and calcium phosphate--1; whereas 73 (94.8%) were mixed stones. Of these, 9 (11.7%) were "predominant" mixed stones, with only one constituent having rich concentration (grade of ++ or more) and all others being either trace or +. The rest 64 (83.1%) were "heterogenous" mixed stones having rich concentration of more than one constituent.
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PMID:Spectrum of pediatric urolithiasis in western India. 180 Mar 38

63 patients with hypocitraturia (44.9% of the total) and 33 patients with hypomagnesiuria (24.8% of the total) received oral magnesium hydroxide and/or Na/K citrate in addition to other therapeutic agents if indicated and a common-sense diet. Hypocitraturic patients were categorized into 3 groups and received 27-81 mEq/day oral citrate according to the deficiency grade. Hypomagnesiuric patients also formed two groups according to the deficiency grade and received 500 and 1,000 mg/day magnesium hydroxide, respectively. Replacement was intermittant and was controlled every 3 months until reaching normal values. We evaluated 28 of 63 hypocitraturic and 15 of 33 hypomagnesiuric patients who had inhibitory deficiency as the sole causal factor of their urolithiasis. After a follow-up of 13.5 +/- 10.2 months, no patient in either group developed a new stone. Citrate and magnesium were increased significantly in the respective groups; calcium and oxalate excretion was lowered, and urine pH and volume increased significantly. A deficiency grade-adjusted and intermittant replacement therapy with Mg and citrate is very effective, has less side effects and ensures good patients compliance.
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PMID:Role of inhibitor deficiency in urolithiasis. II. Deficiency grade-adjusted and intermittent augmentation therapy for magnesium and citrate deficiency. 185 31

Because human urine contains various substances which can affect each other, it is quite difficult to clarify the mechanism of formation of calcium oxalate (CaOx) crystal in urine. The authors recently determined CaOx crystalline content and the concentrations of other substances in urine specimens from patients with urolithiasis and healthy volunteers, and subjected the data to multi-regressive analysis for the purpose of assessing the effect of these urinary substances on CaOx crystal formation. 1. In analysis of urine from patients with urolithiasis, the partial correlation coefficients of CaOx crystal formation with oxalic acid, sodium, calcium, uric acid magnesium were 0.67, 0.28, 0.18, and -0.10, respectively. The formula of regression was as follows: Amount of CaOx crystal (X 10(6) microns3/ml) = 3.59 X 10(-2) Ox (mM/L) + 4.72 X 10(-3) Ca (mM/L) + 4.52 X 10(-3) Na (mM/L) + 2.51 X 10(-4) UA (mM/L) -2.39 X 10(-2) Mg (mM/L) -1.65. The multiple correlation coefficient was 0.759. Thus, in patients with urolithiasis, urinary crystal formation was most dependent on the oxalic acid level, sodium, calcium, and uric acid were found to promote crystal formation, while magnesium to suppress it. 2. In analysis of urine from healthy volunteers, the partial correlation coefficients of CaOx crystal formation with oxalic acid and inorganic phosphorus were 0.51 and -0.24, respectively. The formula of regression was as follows: Amount of CaOx crystal (X 10(6) microns3/ml) = 1.91 X 10(-2) Ox (mM/L) -3.43 X 10(-4) P (mM/L) +0.29 The multiple correlation coefficient was 0.525.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Studies on calcium oxalate crystal formation in urolithiasis. Multi-regressive analysis of urinary CaOx crystalline volumes and the effects of urinary various substances on CaOx crystal formation]. 187 73

A series of 270 paediatric stone patients was studied retrospectively according to the clinical pattern of urolithiasis (age and sex, stone location, stone analysis, recurrence rate) and aetiology of stone disease (infection, anatomical, metabolic or idiopathic). Infection stones occurred earliest and more commonly in males and were usually upper tract struvite calculi related to Proteus infection. Anatomical stones were most commonly associated with pelviureteric junction (PUJ) obstruction and had a high recurrence rate, despite surgical correction of obstruction. Idiopathic stones most resembled those found in adult urolithiasis by virtue of occurring latest, being sited in the ureter more often and being more frequently composed of calcium oxalate. Metabolic stones were most frequently calcium phosphate or cystine and virtually all were renal. They comprised the smallest group but had the highest recurrence rate.
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PMID:Clinical patterns of paediatric urolithiasis. 188 49

A retrospective study was done on the nature and degree of crystalluria in spontaneously voided fasting and postprandial urine of patients with recurrent idiopathic calcium urolithiasis (RCU) divided into normocalciuria (20 males, 20 females) and hypercalciuria patients (20 males, 20 females), and controls (20 males, 20 females). The crystals were obtained using a filter technique and identified by microscopy. In addition, individual data, clinical chemistry variables and indices reflecting the risk of calcium phosphate and calcium oxalate crystallization were evaluated. In contrast to findings of other investigators of crystalluria we observed only a few crystals on the filters. The most frequently occurring phases were (in this order) a urate-containing phase (tentatively termed uric), an amorphous calcium phosphate phase (tentatively termed isotropic) and a phase of spheroid-like particles, not yet definitely characterized (tentatively termed spheroid). Calcium oxalate crystals were found only exceptionally. There was no relationship between the degree of calciuria (normo- versus hypercalciuric RCU) and crystalluria. Among RCU, males generally had a predominance of the isotropic, females of the spheroid phase, as compared with controls. Also, RCU females were generally obese, and their spheroid score and lean body mass correlated negatively and significantly. The calcium phosphate and calcium oxalate risk indices were always low in normal individuals, higher in RCU. Patients of both sexes with urinary stones had normal parathyroid gland function, but higher total calcium in fasting serum and higher urinary pH as compared with controls.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Crystalluria determined by polarization microscopy. Technique and results in healthy control subjects and patients with idiopathic recurrent calcium urolithiasis classified in accordance with calciuria. 188 22

In this study, the relative crystal growth rate (Vcr) of calcium oxalate (Caox) and a number of other parameters were determined in 17-h daily (d) and 7-h nocturnal fractions (n) of whole urine from 20 recurrent Caox stone formers (SF) and 29 age-matched male normal controls (NC). Vcr, which was determined by the gel crystallization method (GCM), showed the largest difference between SF and NC among all parameters under investigation. Mean values (+/- SD) obtained for Vcr were: 0.73 +/- 0.58 (SF-d)/0.21 +/- 0.22 (NC-d; P less than 0.001) and 0.63+/- 0.58 (SF-n)/0.24 +/- 0.25 (NC-n; P less than 0.01). Significantly higher concentrations of Ca and lower concentrations of thermodynamic and kinetic effectors of Caox crystal growth were responsible for the higher crystal growth rates observed in SF as compared with NC, i.e., they should be partially causative in Caox urolithiasis. However, other properties of urine or the urinary tract (potentially, crystal agglomeration and adhesion) must be accounted for in the genesis of Caox stones.
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PMID:Crystal growth of calcium oxalate in urine of stone-formers and normal controls. 188 23

To estimate the epidemiology of upper urinary stones in the elderly, a total of 1,957 patients (1,349 men and 608 women) with urolithiasis were studied. The ratio of men to women was approximately 3:1 in middle-aged (between 30 and 59 years), 1:1 in young (29 or younger) and 1:1 in old patients (60 or older). Compared with the age distribution of the entire Japanese population, the incidence of urinary stones was very low in both male and female children, twice as high in middle-aged men, slightly higher in middle-aged women, and equal or slightly lower in the male and female elderly. Stones of calcium oxalate and uric acid occurred more frequently and those of calcium phosphate and struvite less frequently in men than in women. This tendency was especially obvious in the middle-aged. In the old generation, calcium oxalate stones occurred almost equally in men and women. Results of urinary stone analysis were similar among men of the three generations, although the incidence of uric acid stones increased with patient age. In women, however, the incidence of calcium oxalate was higher in the young and old generations, while that of calcium phosphate was higher in the middle-aged.
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PMID:Epidemiology of urolithiasis in the elderly. 193 39


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