Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020438 (hypercalciuria)
 2,502 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oxalic acid seems to play a far greater role in the formation of calcium oxalate stone than calcium. Three grams of calcium lactate and 3 g of sodium potassium citrate were administered to 46 urolithiasis patients, whose stones were mainly composed of calcium oxalate. Urinary oxalate level was reduced significantly without raising urinary calcium level by the administration of the two drugs for two weeks. The reduction of urinary oxalic acid was particularly remarkable in patients without hypercalciuria. The mechanism of action of these drugs was discussed.
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PMID:Reduction of urinary oxalate by combined calcium and citrate administration without increase in urinary calcium oxalate stone formers. 154 Oct 59

A decrease in bone density of the spine has been reported in individuals with hypercalciuria and the finding of the latter in osteoporosis patients is not uncommon. We studied 21 men and 8 women (mean age 47 +/- 13) with idiopathic hypercalciuria (IHCU) defined by an urinary calcium of more than 7.5 mmol/24 h in men and 6.25 mmol/24 h in women. The duration of IHCU was 10 (+/-) 8 years. Among the 29 patients, 24 had one or more renal calculi. Twenty one had been treated, by low calcium diet only (and diuresis), combined with a thiazide diuretic, or sodium phytate, or phosphorus. Bone mineral content (BMC) was measured in the lumbar spine and the upper end of the femur using an ORIS ODC 200 densitometer and compared with 29 control subjects paired for age and sex. No difference was found between the two groups concerning BMC values in either the spine or the 3 femoral sites (neck, Ward, trochanter). BMC was not correlated with urinary calcium. Thus individuals with IHCU showed no decrease in their bone mass, among this group seen in a department of nephrology. The influence of the treatment of IHCU remains to be defined.
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PMID:[Idiopathic hypercalciuria and bone density]. 157 44

To assess a possible heritability of a disturbed calcium metabolism in relation to blood pressure regulation, 28 young normotensive offspring of either hypertensive or normotensive parents were studied while administered a defined diet with daily sodium chloride of 6 and 20 g/day for 7 days each. Before the high salt diet was begun, the cytosolic calcium concentration ([Ca2+]i) in platelets was elevated in offspring of hypertensive parents, whereas serum electrolytes, plasma renin activity, plasma catecholamines, and 24-hour urinary excretion of sodium and calcium showed no difference between the two groups. On exposure to a high salt diet, the mean blood pressure increased (from 80 +/- 2 to 85 +/- 2 mm Hg, p less than 0.05) in offspring of hypertensive parents. These changes in mean blood pressure were positively correlated with the basal platelet [Ca2+]i (r = 0.61, p less than 0.01), whereas [Ca2+]i did not demonstrate any significant changes. When the subjects were administered the high salt diet, plasma ionized calcium decreased (from 2.37 to 2.21 meq/l, p less than 0.05) and 1,25-dihydroxyvitamin D3 increased (from 32.7 to 40.8 pg/ml, p less than 0.05) with a transient relative hypercalciuria in offspring of hypertensive parents. This increase of 1,25-dihydroxyvitamin D3 was significantly correlated with the changes in mean blood pressure (r = 0.62, p less than 0.01). Disturbed intraplatelet and systemic calcium metabolism may be of predictive value in the development of hypertension.
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PMID:Disturbed calcium metabolism in offspring of hypertensive parents. 159 47

Because cystic fibrosis (CF) epithelia have ion transport abnormalities that may in part be regulated by intracellular calcium metabolism, and the kidney is actively involved in both ion transport and calcium homeostasis, we have investigated renal calcium handling in CF. Twenty-four-hour urine collections were analyzed in 34 CF patients (age 5 to 35 years) and kidney ultrasound studies were performed in 17 CF patients (age 6 months to 23 years). Renal histologic findings at postmortem examination of 14 CF patients (age 4 months to 23 years) were compared with those of 12 patients (age 11 months to 17 years) with other chronic illnesses (6 congenital heart disease, 6 malignancy). In 30 of the 34 CF patients urinary calcium excretion was normal (less than 4 mg (0.1 mmol)/kg/24 hr). Four CF patients had hypercalciuria (calcium excretion 4.4 to 8.8 mg (0.11 to 0.22 mmol)/kg/24 hr). However, these patients had other possible explanations for hypercalciuria, such as immobilization (n = 2), increased dietary sodium load (n = 1), and glucocorticoid therapy (n = 1). None of the 17 patients examined by renal ultrasonography had nephrocalcinosis. Five CF patients had histologic evidence of sparse nephrocalcinosis at autopsy. However, 6 of 12 autopsy kidney specimens from patients with other chronic illnesses and similar preterminal events also showed nephrocalcinosis. The hypercalciuria and nephrocalcinosis in CF and other chronic debilitating diseases may be explained by factors known to affect calcium handling. Our evidence does not support a primary renal defect as the basis of hypercalciuria and nephrocalcinosis in CF.
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PMID:Renal calcium handling in cystic fibrosis: lack of evidence for a primary renal defect. 169 Jul 95

We have studied urinary sodium and magnesium excretion in 30 normal subjects (15 women and 15 men, mean age 43 +/- 14 years, mean weight 74 +/- 18 Kg) and in 60 hypercalciuric stone-forming patients, 30 with renal hypercalciuria (HR) (15 women and 15 men, mean age 39 +/- 10 years, mean weight 71 +/- 16 Kg) and 30 with absorptive hypercalciuria (HA), (15 women and 15 men, mean age 41 +/- 13 years, mean weight 69 +/- 12 Kg). The diagnosis of hypercalciuria and the classification in HA and HR was made with our ambulatory study protocol. Hypercalciuria was defined by a daily calcium excretion above 300 mg (men) or 220 mg (women), and patients with fasting calcium to creatinine ratio, and calcium per 100 ml of glomerular filtrate average value above 0.11 were considered to have HR. Control subjects and hypercalciuric patients were maintained on a diet containing 1200 mg Ca, 800 mg P, 200 mg Mg and 100 mmol Na per day for a 7-day period. Two 24-hour urine samples were collected on days 6 and 7 of this diet. On the morning of day 8, following a 12-hour fast, 300 ml of distilled water was drunk and a 2-hour urine sample was collected. A blood sample was taken halfway this time. In all blood and urine samples, calcium, magnesium, sodium, phosphorus and creatinine were quantified. Creatinine clearance and calcium, sodium and magnesium per 100 ml of glomerular filtrate were calculated from these determinations.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Urinary excretion of sodium and magnesium in idiopathic hypercalciuria]. 182 17

Increased luminal calcium decreases potassium secretion in microperfused rat distal tubule. To determine if such an effect is also present in vivo, we evaluated renal potassium excretion in 49 children with idiopathic hypercalciuria (urinary excretion of Ca = 5.5 +/- 1.3 mg/kg/day) and in 214 age-matched control children (urinary excretion of Ca = 1.9 +/- 0.3 mg/kg/day). In comparison to controls, hypercalciuric children had significantly increased levels of sodium excretion (fractional excretion of Na = 0.7 +/- 0.3 vs. 0.6 +/- 0.3%, respectively; p less than 0.001) and decreased levels of fractional potassium excretion (7.2 +/- 2.9 vs. 9.2 +/- 3.4%, respectively; p less than 0.001) and of the transtubular potassium concentration gradient (4.2 +/- 1.5 vs. 5.9 +/- 1.5, respectively; p less than 0.001). All indices of potassium excretion correlated significantly and inversely with urinary calcium excretion (p less than 0.001). After an oral calcium load, performed in 30 hypercalciuric children, the increased rates of urinary calcium excretion were accompanied by increased rates of urinary sodium excretion and by a significant decrease in the transtubular potassium concentration gradient. These results support the hypothesis that increased luminal calcium concentration also inhibits renal potassium secretion in man.
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PMID:Renal potassium excretion is reduced in children with idiopathic hypercalciuria. 182 84

Urinary excretion of sodium and calcium was examined in hypertensive (n = 8) and normotensive (n = 7) subjects following infusion of 2% saline at a rate of 11 mL/min for 90 min. The urinary sodium excretion was 204 +/- 38 (mean +/- SEM) muEq/min in normotensives and 233 +/- 28 muEq/min in hypertensives before infusion of saline and increased maximally to 499 +/- 114 muEq/min (P less than .05) and to 928 +/- 68 muEq/min (P less than .01), respectively, after saline infusion. In normotensives, urinary calcium excretion did not change significantly; however, in hypertensives excretion increased markedly (P less than .01) from 6.1 +/- 0.7 muEq/min to 12.3 +/- 1.6 muEq/min. Plasma atrial natriuretic peptide (ANP) levels increased significantly (P less than .05) in both groups. Serum ionized calcium and plasma parathyroid hormone (PTH) levels did not change significantly. The increments of urinary sodium and calcium and of plasma ANP, as well as the preinfusion plasma PTH level, were significantly (P less than .05) higher in hypertensives than in normotensives. The present study showed that exaggerated natriuresis was accompanied by hypercalcinuria and an enhanced rise in plasma ANP in hypertensives. Basal levels of plasma PTH were elevated in hypertensives. The calcium deficiency may be attributable to a close relationship between urinary sodium and calcium, and causally related to the disturbance of sodium and volume homeostasis in hypertension, which results in exaggerated natriuresis.
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PMID:Effect of saline infusion on urinary calcium excretion in essential hypertension. 182 96

Hypercalciuria has been reported in rats with mild hyperprolactinemia due to implantation of anterior pituitary glands under the kidney capsule and in rats bearing transplantable tumors that secrete large amounts of prolactin (PRL) and growth hormone (GH). We studied Buffalo rats implanted subcutaneously with the new MMQ pituitary tumor line that secretes only PRL. Urinary calcium excretion increased as the tumors grew. Three weeks after tumor implantation in female rats, the urinary calcium excretion was 1.102 +/- 0.092 mg/100 g body weight (BW).24 hours compared with controls, 0.296 +/- 0.079, P less than .0005. Male tumor-bearing rats also had increased urinary calcium excretion compared with male controls. In tumor-bearing rats the urinary calcium excretion factored for urinary sodium excretion, dietary calcium intake, or urinary creatinine excretion was elevated. Urinary calcium excretion was correlated with serum PRL levels and with estimated tumor volume. Serum calcium, immunoassayable parathyroid hormone, and urinary cyclic adenosine monophosphate (cAMP) excretion were normal in the tumor-bearing rats. There was some evidence of loss of bone calcium in rats bearing the MMQ tumor, and serum levels of calcitonin were decreased. These results are similar to those found in anterior pituitary-grafted hypercalciuric rats. It is unlikely that parathyroid hormone (PTH) abnormalities are responsible for the hypercalciuria in the MMQ-bearing rats. The pituitary gland may have an effect on the distal renal tubule to decrease calcium reabsorption.
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PMID:Hypercalciuria in a new rat model of hyperprolactinemia. 184 86

Hypercalciuria is one of the main causes of recurrent generation of urinary calcium-containing calculi. 107 patients with recurrent calcium nephrolithiasis were examined and results presented. Concentrations of potassium, sodium, chlorides, calcium, phosphorus, uric acid and creatinine were investigated in serum and urine, as well as indices of acid-base balance in arterial blood. pH-metry, "preliminary" and oral calcium tolerance test were also carried out. The microcomputer data analysis established that the diagnosis of primary hyperparathyroidism may be identified in case of increased serum calcium level before and after calcium load test, the same of parathyroid, and increased urinary cAMP excretion. Renal hypercalciuria is characterized by low blood calcium level in both periods of the oral test, high basal calciuria, increased urinary cAMP excretion and its slight decrease after the oral calcium load test, by a tendency to lower serum magnesium levels in high magnesuria. The patients with absorptive hypercalciuria had an upper normal or increased blood calcium level, a significant calcemic and calciuric "response" to the calcium load, reduction in urinary cAMP elimination and more severe decrease (close to 0) of these indices after oral calcium load and normal magnesium levels in blood and urine. On a base of the "preliminary" test data the patients with relapsing calcium nephrolithiasis and metabolic disorders may be differed from those without calcium and phosphorus metabolic deteriorations. The "preliminary" test defines indications for the oral calcium tolerance test, automatic diagnosis and computer data storage facilitate physician to work and to solve problems of the patients' survey.
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PMID:[The comprehensive examination of patients with recurrent calcium nephrolithiasis]. 185 97

Thirteen urolithiasis patients with unilateral obstructive uropathy were treated with percutaneous nephrostomy (PCN) either for urinary diversion, endopyelotomy, nephrolithtotmy or chemolysis. After percutaneous nephrostomy, the individual urine volume, creatinine clearance (Ccr), urinary absolute and fractional excretions of sodium, potassium, calcium, magnesium and inorganic phosphate were measured separately in timed urine collections from a pigtail catheter and from the urethra. The data showed that Ccr and the absolute urinary excretions of sodium, potassium, calcium, magnesium and inorganic phosphate were significantly lower in the PCN kidney immediately or 2 days after relief of obstruction. The ratio of total urinary calcium excretion to urinary creatinine excretion in the obstructed kidney was significantly greater than that in the contralateral kidney. The fractional excretions of calcium and magnesium increased as renal function decreased. The results showed that when the total Ccr is below normal, the apparent excretion of urinary calcium will be underestimated. However, when the total Ccr of patients is within normal range, hypercalciuria may be detected adequately and thus favors early implementation of an appropriate therapeutic strategy.
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PMID:Reduction of calcium excretion in the stone-forming kidney in unilateral ureteral obstruction. 188 28


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