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)

In the literature there is a paucity of references on urolithiasis in children with spinal cord injury. In this paper 28 cases of urolithiasis in 97 children with spinal cord injury are analysed. An attempt is made to evaluate the role of hypercalcemia, hypercalciuria and urinary tract infection in the genesis of these calculi.
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PMID:Urolithiasis in children with spinal cord injury. 43 66

Urine calcium excretion is known to be directly correlated with the level of dietary protein intake. In this experiment we examined the persistence of the hypercalciuria induced by the consumption of high protein diets, and the mechanism of the calciuric response. In a 95-day metabolic study, each of six adult male subjects received formula diets supplying 12 g nitrogen or 36 g nitrogen, and approximately 1400 mg calcium per day. Urine calcium increased rapidly and significantly from an average of 191 mg/day on the 12 g nitrogen diet to 277 mg/day on the 36 g nitrogen diet. There was no significant difference in the apparent absorption of calcium, so that overall calcium balance was -37 mg/day on the 12 g nitrogen diet, and significantly lower at -137 mg/day in subjects consuming the high protein diet. Levels of urinary hydroxyproline, serum insulin, and parathyroid hormone were not significantly increased by high intakes of protein. A decrease in the fractional reabsorption of calcium by the kidney seems to be the most likely cause of the protein-induced hypercalciuria. The consumption of high calcium diets is unlikely to prevent the negative calcium balance and probable bone loss induced by the consumption of high protein diets.
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PMID:Protein-induced hypercalciuria: a longer term study. 43 6

Calcium absorption in the jejunum and ileum of patients with absorptive hypercalciuria was studied by in vivo intestinal perfusion. Net calcium absorption in the jejunum was markedly increased at four luminal calcium concentrations (1 to 20 mM) in the patients with absorptive hypercalciuria when compared to that in normal subjects. In the ileum, net calcium absorption was only slightly increased in the patients with absorptive hypercalciuria. Experiments with radioactive calcium (47Ca) revealed increased unidirectional flux out of the jejunal lumen in the patients but no difference in the unidirectional flux into the lumen, when compared to that in normal control subjects. Net magnesium absorption was normal in the patients. These results suggest that hyperabsorption of calcium in patients with absorptive hypercalciuria is mainly due to enhanced calcium transport in the jejunum and that the defect is specific for calcium since magnesium is absorbed normally.
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PMID:Selective jejunal hyperabsorption of calcium in absorptive hypercalciuria. 43 48

Eighty patients with proved calcium urolithiasis participated in an outpatient study designed to define the most likely metabolic problem related to the cause of the stone disease. Diagnostic categories included absorptive hypercalciuria (33 patients), renal leak hypercalciuria (20 patients), hypomagnesiumuria (27 patients), hyperuricemia and hyperuricuria (16 patients), hyperoxaluria (15 patients), normal stone-former (4 patients), renal tubular acidosis (2 patients) and suspicion of hyperparathyroidism (7 patients). Of the 80 patients 40 had more than 1 defect. Patients with a high suspicion of hyperparathyroidism were excluded from the study. Based on these criteria treatment plans incorporating medications, diet or both were instituted. Of 21 patients observed for greater than 2 years 90 per cent have shown no new stone disease.
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PMID:Outpatient evaluation of patients with calcium urolithiasis. 43 49

The authors report on the clinical, biological and radiological anomalies observed in a series of 42 cases of idiopathic hypercalciuria. An histological bone study showed "osteomalacia" type changes (an increase in the osteoid volume and a decrease in the mineralization speed). The Ca45 isotope studies showed that there was an exchangable pool of calcium and a turnover, which was generally low. A study of the kidney functions revealed a decrease in the tubular reabsorption of calcium, while that of phosphorous remained within normal limits. There was no case of hyperparathyroidism in this series. The authors pose the question of whether the failure of calcium to settle on the tissues and the lack of tubular reabsorption of calcium, does not result from the relatively ineffective action of the endogenous circulating parathyroid hormone.
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PMID:[Idiopathic hypercalciuria. Correlative study of bone tissue and phosphocalcium investigations]. 44 70

Fifteen cases of hypervitaminosis D in childhood are reviewed. In all of them, vitamin D was given following medical prescription. In four occasions, excessive dosage of vitamine D impaired the evolution of a previous nephropathy. The clinical, analytical, radiological and histological findings as well as the therapeutical aspects are commented. Hypercalcemia, hypercalciuria, polyuria with hypostenuria, renal failure, bone lesions and nephrocalcinosis are the most prominent features of the picture. Occasionally, arterial hypertension and glycosuria were found. Prednisone, thyrocalcitonine and phosphates were used as therapeutical means. In spite of nephrocalcinosis and renal failure generally present at diagnosis, the clinical course was rather good.
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PMID:[Hypervitaminosis D. Review of fifteen cases]. 44 41

Urinary saturation with respect to calcium oxalate monohydrate was measured in 111 consecutive patients with calcium nephrolithiasis. Each patient also was evaluated by a detailed conventional metabolic protocol. Patients with idiopathic hypercalciuria produced abnormally oversaturated urine more frequently than normal subjects and normocalciuric patients, but normocalciuric patients had unexpectedly high levels of urine saturation. Measuring levels of calcium concentration, oxalate concentration, or the chemical concentration product of calcium and oxalate in urine did not predict oversaturation. During thiazide treatment, saturation level tended to fall if it was initially elevated, whether the patient was hypercalciuric or not. Patients whose urine was not remarkably oversaturated showed no tendency to elaborate even less saturated urine during thiazide treatment; instead, the average calcium oxalate saturation level remained constant. Direct urine saturation measurements can detect a small but significant number of normocalciuric patients who have marked oversaturation with respect to calcium oxalate and appear to benefit from treatment.
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PMID:Urinary saturation measurements in calcium nephrolithiasis. 44 49

A specific competitive protein binding assay for 25 hydroxy-vitamin D and 24, 25 dihydroxyvitamin D in human serum has been developed. It includes a chromatographic step on a Sephadex LH 20 column to specifically separate the metabolites. The average value was for 25 hydroxyvitamin D 11.9 +/- 6.6 Ng/ml (mean +/- SD) and for 24, 25 dihydroxyvitamin D 6.85 +/- 3.29 ng/ml in ten normal subjects sampled in autumn. In hepatic insufficiencies the mean level of 25 hydroxyvitamin D was lower and the mean level of 24, 25 dihydroxyvitamin D was higher than in normal subjects. In patients with renal insufficiency the 25 hydroxyvitamin D levels were normal and the 24, 25 dihydroxyvitamin D levels were low but not suppressed. The two sterols were also determined in some patients with idiopathic hypercalciuria.
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PMID:[Simultaneous radiocompetitive assay for 25 hydroxyvitamin D and 24, 25 dihydroxyvitamin D in human serum (author's transl)]. 44 44

The persistence of hypercalciuria (HCU), despite long-lasting calcium restriction in the diet in patients with absorptive HCU type I gives evidence of an additional endogenous source of calcium contributing to the pathogenesis of this disorder. The role of calcium mobilization from the bone is documented by the effective suppression of enhanced calcium mobilization from the bone, by means of calcitonin load in 5 patients with absorptive HCU type I and comparison with 7 normal controls.
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PMID:Calcitonin load in absorptive hypercalciuria type I. 44 94

We have studied 83 patients with recurrent calcium stone formation in an attempt to determine an approximate incidence of metabolic disturbances associated with stone disease. Male veterans (n = 42), male non-veterans (n = 13), and women (n = 28) composed the group. We divided the groups in such fashion because they represented generally two distinct socioeconomic groups. Primary hyperparathyroidism was present in 19 per cent of the subjects; a marked predominance of women (15/16) was noted. Hypercalciuria of renal or intestinal origin was present in 23 per cent of the group. Of interest was a group of male veterans (17/83) in whom normocalciuria, normocalcemia, and normal serum phosphate were associated with high values of immunoreactive parathyroid hormone. These subjects had low urine phosphate. This set of findings indicates that these patients may be a new subgroup of stone-forming patients. Metabolic abnormalities could not be detected in 38 per cent of the patients. Classification of stone subjects is essential for rational management.
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PMID:Some characteristics of recurrent calcium stone formers in Puerto Rico. 45 11


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