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)

We report the results of an oral tolerance test performed in 317 patients with kidney stones. In order to avoid PTH or AMPc measurements, and therefore to reduce costs and time to get the results, we measured the tubular maxima of phosphate per glomerular filtration rate (TmP04/GFR, the phosphate threshold). Urine collections from 7 to 9 h and from 9 to 13 h were obtained. The samples were analyzed for calcium, creatinine and phosphorus content. All patients ingested 1 g of calcium mixed in a meal at 9 o'clock. Venous blood samples were obtained for calcium, creatinine and phosphorus measurements, previous to the calcium ingestion. Urinary calcium to creatinine ratio, before and after the calcium-load, as well as TmP04/GFR were calculated. In 97 subjects (30.8%) there were no calcium metabolism abnormalities. Idiopathic hypercalciuria was present in 183 (57%) and primary hyperparathyroidism in 37 (11.7%). Idiopathic hypercalciuria was classified in four subgroups: absorptive hypercalciuria with normal serum phosphorus, absorptive hypercalciuria with low serum phosphorus (renal phosphate leak), renal hypercalciuria with normal phosphorus and renal hypercalciuria with low serum phosphorus.
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PMID:[Usefulness of oral calcium test in renal lithiasis]. 792 97

Careful examination as well as biochemical and hormonal investigations should be performed in men suffering from vertebral crush fractures, in order to detect a destructive skeletal process (multiple myeloma, bone metastatic lesions, lympho and myeloproliferative disorders), a mineralization defect (osteomalacia) or a secondary osteoporosis: primary hyperparathyroidism, hypogonadism, hyperthyroidism, renal hypercalciuria, alcoholism and tobacco smoking. The diagnosis of idiopathic osteoporosis should be made only after these causes have been excluded; the pathogenesis of the disease is unclear but risk factors have been identified: family history of osteoporosis, low dietary calcium intake, delayed puberty, ethanol use, tobacco smoking, inactive lifestyle and lean body build. Correction of risk factors, calcium supplementation, regular program of weight bearing physical activity, in some instances correction of testosterone deficiency may be of benefit to reduce bone loss. Severe osteopenia or osteoporosis may require sodium fluoride therapy.
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PMID:[Male osteoporosis]. 793 30

No satisfactory medical therapy exists for the treatment of primary hyperparathyroidism. Calcitonin and diphosphonates do not give good long-term control. This work examines the efficacy of the somatostatin analogue octreotide in the management of hyperparathyroidism. Twenty-one patients were admitted before parathyroid surgery and were treated for 6 days with subcutaneous octreotide 100 micrograms twice daily. Fasting blood samples were taken for determination of serum levels of calcium and parathyroid hormone, and 24-h urinary calcium excretion was measured before and after treatment. A significant decrease in urinary calcium was demonstrated, but the reduction in serum calcium level was not statistically significant and there was no change in serum parathyroid hormone concentration. Octreotide may provide therapy for patients with hyperparathyroidism and for those who have undergone unsuccessful neck exploration or who are unfit for operation. It may ameliorate hypercalciuria and reduce stone formation. The octapeptide may also have a potential role as a diagnostic test in primary hyperparathyroidism by determining the symptomatic effect of reducing raised levels of serum and urinary calcium.
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PMID:Somatostatin and primary hyperparathyroidism. 795 42

The Jansen type of metaphyseal dysplasia (JMD) is a rare disorder characterized by growth disturbance and progressive metaphyseal changes initially reminiscent of rickets or primary hyperparathyroidism. Seven of the 16 patients described until now presented with hypercalcaemia of unknown origin. We report studies of calcium metabolism in a hypercalcaemic girl with JMD during the first 3 years of life. The patient presented with hypercalcaemia, hypercalciuria, elevated urinary phosphate and cyclic adenosine monophosphate (AMP) excretion as well as increased 1,25-dihydroxyvitamin D concentrations in serum despite suppressed or low normal values of circulating intact parathyroid hormone (PTH) and PTH related peptide (PTHrP). Measurements of biochemical indices of bone turnover indicated increased bone resorption without sufficient compensatory bone formation. The study suggests that the hypercalcaemia in our patient was caused by an unknown factor, which is not PTH or PTHrP, with osteolytic activity and stimulatory effect on the proximal kidney tubule.
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PMID:Calcium metabolism in the Jansen type of metaphyseal dysplasia. 827 22

Familial benign hypercalcemia (FBH, or hypocalciuric hypercalcemia) is characterized by inheritance, in an autosomal dominant pattern, of lifelong hypercalcemia without hypercalciuria, which is often mistaken for classical primary hyperparathyroidism. Recently, the FBH trait was linked, in four families, to chromosome 3q. We report genetic linkage analysis in 140 persons from five additional families having FBH (65 affected, 67 unaffected, and 8 unclassifiable). In four families, FBH mapped to chromosome 3q, between D3S1215 and D3S20, maximum multipoint lod score 12.9. By contrast, in the fifth kindred FBH mapped to chromosome 19p13.3, tightly linked to the marker loci D19S20 and D19S266 (two-point lod score at recombination fraction = .001 is 3.44 and 3.70, respectively). Thus, the FBH phenotype results from mutations at two separate loci on chromosomes 3q and 19p.
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PMID:Genetic linkage analysis in familial benign (hypocalciuric) hypercalcemia: evidence for locus heterogeneity. 831 84

The effects of endocrine disease on bone mass continue to attract attention. Investigations include the effects on the skeleton of thyroid disease, primary hyperparathyroidism, and their treatment. The effect of growth hormone replacement in adults with panhypopituitarism has also been investigated; children with treated growth hormone deficiency appear to reach adulthood with low bone mass. The indications for surgery in asymptomatic primary hyperparathyroidism have recently been reviewed. The associations between autoimmune thyroid disease and connective tissue disease have been investigated. Although patients with Graves' disease are frequently positive for antinuclear antibodies, there appears to be no increased risk of systemic autoimmune disease. The possible pathogenesis of diabetic bone disease via calcium malabsorption, hypercalciuria, reduced bone formation, and collagen abnormalities has been reviewed. A long-term study has clarified the links among diabetic control, limited joint mobility, nephropathy, and retinopathy. The possible mechanisms by which pregnancy may induce remission in rheumatoid arthritis have been discussed.
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PMID:Endocrine disease. 843 94

The hypercalciuria that eventually remains after the successful removal of a solitary parathyroid adenoma may originate from excessive intestinal calcium absorption, bone resorption or deficient renal reabsorption. In order to clarify this question, ten patients surgically cured from primary hyperparathyroidism (PHPx), ten age-matched normal subjects and five nephrolithiasic patients with renal hypercalciuria (RH) were studied after five days on a low calcium diet, either during fasting or after oral calcium load. Fasting serum calcium, amino-terminal and intact PTH levels and also urinary cAMP excretion were normal in every individual patient. Serum ionized calcium and inulin clearance (GFR) were used for calculations of the filtered load (FL Ca) and the fractional excretion of calcium (FE Ca). Six PHPx patients displayed fasting calciuria above the upper limit calculated for control subjects, despite having the lowest GFR and FL Ca (p < 0.05 vs control). These patients (h-PHPx) had a small calciuric response to oral calcium load. Serum 1,25-(OH)2D3 and 25OHD3 did not correlate with calciuria. Our findings exclude intestinal hyperabsorption and excessive bone resorption in h-PHPx patients, and strongly suggest a renal tubular defect in calcium reabsorption as the cause of their hypercalciuria. This defect could be primary, as in RH, but only three hPHPx patients had recurrent kidney stones before surgery. On the other hand, as a negative correlation between GFR and FE Ca was only found in PHPx patients, it seems probable that the disturbances in glomerular and tubular functions were secondary to the long standing hypercalcemic hyperparathyroidism.
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PMID:The cause of maintained hypercalciuria after the surgical cure of primary hyperparathyroidism is a defect in renal calcium reabsorption. 885 86

The present series comprises 2086 consecutive patients who were studied in a stone clinic during a period of 15 years. Each patient was subjected to a comprehensive protocol including a fully biochemical investigation. Calcium stones were by far the commonest accounting for 61% of cases; infection, uric acid/calcium oxalate and cystine stones accounted respectively for 24%, 8%, 5% and 2%. Nephrolithiasis was more prevalent in males with the male to female ratio 1:0.76, on the other hand infection stones were more frequent in females with the male to female ratio 1:1.6. The peak age incidence of renal calcium stones occurred in the third to fifth decades, although about 3.4% reported onset of disease in the first and second decades of life. The onset of cystine stones was always in the first and second decades, while uric acid stones affected older patients. Renal stones were recurrent in about 50% of cases. In a retrospective analysis it was found the interval to first recurrence to be less than 5 years in about half patients. The cystine and uric acid groups had the highest rate of recurrence. In patients with calcium stones a definite metabolic or mechanical cause for their stones was found respectively in 8.2% and 10.1%. Particularly primary hyperparathyroidism was revealed in 2.8%. A metabolic defect could be found in 54% of the patients with idiopathic calcium stones. In these patients with idiopathic calcium stones the prevalence rate of hypercalciuria was 33%. In patients with uric acid stones and with mixed uric acid/calcium oxalate stones a definite metabolic cause for their stones was found respectively in 9.5% and 4.1% whereas an underlying disease of the urinary tract was diagnosed respectively in 8.5% and 6.2%. In patients with struvite stones the incidence of persistent infection was 46% (Proteus 18%). In this group the presence of an underlying disease of the urinary tract was diagnosed in 18.8% whereas a definite metabolic disease was demonstrated in 8.5%, a urinary risk factor for metabolic stone disease in 42% and a previous episode of metabolic stone disease in 33%.
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PMID:Clinical observations on 2086 patients with upper urinary tract stone. 893 17

The different subgroups of hypercalciuria cannot be separated clearly by the Pak calcium-load test. To improve the diagnosis and therapy we examined all relevant parameters of calcium metabolism in 32 patients with calcium urolithiasis and hypercalciuria (> 6.25 mmol/day). We also conducted bone mineral density measurements as well as the Pak calcium-load test. In most cases the pathophysiological constellations which Pak takes as the basis for his classification of hypercalciuria could not be shown. To date, diagnostics only insufficiently explains the genesis of hypercalciuria (except pHPT). As a consequence, a therapeutic problem arises: a low-calcium diet should not be generally recommended, since some patients may develop osteopenia. From our investigation the following diagnostic and therapeutic conclusions can be drawn: (1) Hypercalciuria in primary hyperparathyroidism should be treated by surgical removal of the adenoma. (2) The parathormone-independent osteogenic form should be treated with thiazides. (3) Hypercalciuria with increased 1.25-dihydroxyvitamin D should be treated by low-calcium diet.
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PMID:[Studies of calcium metabolism in patients with hypercalciuria]. 899 31

In recurrent calcium stone formers interfering factors or changes in receptor sensitivity may alter the interrelationships among calcium-regulating hormones, and hormonal behavior often does not fit with the theoretical assumptions. The vitamin D system appears to have the most important metabolic and clinical effects. Abnormal up-regulation of the synthesis of calcitriol and the consequent parathyroid hormone (PTH) suppression can induce hypercalciuria. Consequently, the hypocalciuric effect of thiazide would be caused by an enhanced response to PTH and by a reduction in 1,25(OH)2-vit D. A negative role of vitamin D on the skeleton has been observed in the presence of a negative calcium balance. Moreover, vitamin D also plays a role in urine oxalate excretion. PTH seems not to be directly stimulated in hypercalciuria and recurrent calcium nephrolithiasis, and patients with hyperparathyroidism and recurrent calcium nephrolithiasis show a similar degree of bone demineralization, irrespective of the presence of absence of the so-called 'primary hyperparathyroidism.' Calcitonin plays a contributory role in the pathogenesis of recurrent calcium nephrolithiasis that seems to be strictly related to dietary calcium intake. A higher sensitivity of thyroid C cells, particularly in absorptive hypercalciuric patients, could be related to the pathogenesis of hypercalciuria and contribute to its persistence.
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PMID:Calciotropic hormones and nephrolithiasis. 938 31


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