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)

A 14-year-old Turkish boy had severe rickets that had been clinically evident since he was 2 years of age. When he was 5 years of age, he had normal serum calcium and phosphorus levels and increased alkaline phosphatase activity. Treatment with modest dosages of vitamin D (5000 U/d for 3 weeks) resulted in hypercalcemia. At 10 years of age, high-dose vitamin D (40,000 U/d) plus phosphorus (1.1 g/d) therapy for 20 days resulted in symptomatic nephrolithiasis. When, 14 years of age, he had normocalcemia, hypophosphatemia, increased alkaline phosphatase activity, and normal circulating parathyroid hormone concentration. Levels of 25-hydroxyvitamin D were normal but those of 1,25-dihydroxyvitamin D were markedly increased. Rickets and osteopenia were evident on radiographs, and osteomalacia was present on trabecular bone obtained at biopsy. Balance study results showed increased intestinal absorption of calcium and phosphorus, hypercalciuria, and increased urinary phosphorus excretion. This patient manifests an unusual form of hypophosphatemic rickets in which hypercalciuria is a cardinal feature. In contrast with most varieties of hypophosphatemia, this disorder is characterized by appropriately increased production of 1,25-dihydroxyvitamin D in response to hypophosphatemia. It is recommended that urinary calcium excretion be assessed in all patients with hypophosphatemic rickets so that appropriate therapy will be instituted.
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PMID:Hypercalciuric hypophosphatemic rickets, mineral balance, bone histomorphometry, and therapeutic implications of hypercalciuria. 278 97

The causes of impaired calcium, phosphorus and vitamin D metabolism in diabetic patients which in the long run lead to demineralization of bone can be summarized into several main groups. Above all disorders of calcium absorption from the small intestine are involved, associated with impaired absorption of vitamin D and its reduced conversion into active metabolites in the liver and kidneys. An increased elimination of calcium from the organism may also play a part (hypercalciuria, excretion in the faeces and sweat), hormonal changes (secondary hyperparathyroidism) and finally changes in the metabolism of the organic bone constituent--osteoid. Subsequent work will deal with the prevalence of osseous changes in diabetics, early diagnosis and rational treatment and possible prevention of these changes.
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PMID:[Diabetic osteopathies. 1. Etiologic factors and theoretical prerequisites for the development of bone demineralization in diabetics]. 280 Mar 64

Vitamin D deficiency is associated with a generalized aminoaciduria which has been shown to be independent of parathyroid hormone (PTH) and urinary cyclic AMP excretion. To further characterize the mechanism underlying the tubulopathy, weanling rats were placed on one of the following diets for 5 weeks: (1) control [0.7% phosphorus (P), 5.5 micrograms % vitamin D]; (2) D-P- (0.1% P, 0 vitamin D); (3) D+P- (0.1% P, 5.5 micrograms % vitamin D); (4) D-P+ (0.3% P, 0 vitamin D); (5) D-P++ (0.7% P, 0 vitamin D). All diets contained 1.2% calcium (Ca). A group of rats raised on D-P++ for 4 weeks were fed D-P- for 7 days after which they received 500 pmol of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3; SUPP] or an equal volume of the vehicle (ETH). The above diets resulted in partial vitamin D depletion in that 1,25(OH)2D levels were 50.25-79 pg/ml in the presence of very low 25(OH)D concentrations. Augmentation in the urinary excretion of 6 out of 8 amino acids measured was observed in P depletion irrespective of vitamin D status. For the most part, acute supplementation with 1,25(OH)2D3 did not ameliorate the tubulopathy. Plasma PTH and Ca concentrations remained normal in all diets, except D+P-, where plasma Ca was 15.88 +/- 0.54 mg/dl. P depletion was associated with hypercalciuria, hypophosphatemia, avid reabsorption of P and growth retardation, irrespective of vitamin D status. Using taurine as a representative of the amino affected, there was a strong correlation between urinary taurine on the one hand and dietary P content (r = 0.613), plasma P (r = 0.399) and 1,25(OH)2D levels (r = -0.576) on the other. The present study suggests that the aminoaciduria of vitamin D deficiency is not related to elevated levels of PTH. A similar defect may be produced by P depletion, suggesting the possibility of a common pathway for the effect.
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PMID:Effect of vitamin D deficiency on amino acid excretion in the phosphate-depleted rat. 281 86

Using the method of assessment of clavicular corticodiaphyseal indices, the authors investigated the mineralization of bones in a group of 215 type II diabetics and in 40 type I diabetics. From both groups patients were selected without detectable complications and these were compared with a sub-group of patients who had some complications. Furthermore the authors investigated the number of fractures of vertebral bodies and other bones. The poorest results as regards mineralization were found in complications which interfere with calcium absorption: enteropathies, chronic pancreatitis, gastrectomies, renal disease and in women also liver disease, in both with impaired vitamin D conversion. An adverse effect was exerted also by a reduced dietary calcium intake in subjects with lactose intolerance or increased urinary calcium excretion in idiopathic hypercalciuria. Low values were recorded in all patients with motor disorders in angiopathies, otherwise this complication alone did not cause major decalcification. Hysterectomy with ovariectomy were manifested by decalcification only in women where the operation was performed during a certain period before the menopause. Neuropathy and retinopathy alone without impaired locomotor activity do not cause deterioration of the bone mineralization in diabetics. Surprisingly good results were achieved also in a group of diabetics with steatosis of the liver but without severe damage of liver function. With a exceptions the number of fractures of vertebral bodies and other bones correlated with the level of their mineralization.
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PMID:[Diabetic osteopathies. 3. The effect of diabetic complications on bone mineralization]. 281 5

Renal ultrasonography was performed on 23 patients with X-linked hypophosphatemic rickets (XLH) and 11 patients with autosomal recessive vitamin D-dependent rickets (ARVDD). A pattern of increased echogenicity of the renal pyramids (ERP) was identified in 11/23 patients with XLH and 3/11 patients with ARVDD; this ultrasonographic finding has previously been associated with medullary nephrocalcinosis. Patients with XLH and ERP had significantly higher mean serum calcium and phosphate concentrations, more frequent episodes of hypercalcemia, and higher doses of oral vitamin D and phosphate during the first 3 years of therapy. Episodes of hypercalcemia were more frequent when patients received higher doses of vitamin D2 (greater than 4000 IU/kg/day) or 1,25-dihydroxycholecalciferol (greater than 40 ng/kg/day). Episodes of hypercalciuria were significantly increased at doses of greater than 20 ng/kg/day 1,25-dihydroxycholecalciferol. In patients with ARVDD, ERP was also correlated with vitamin D dose and frequency of hypercalcemia episodes. ERP was not associated with an elevation of serum creatinine or loss of urinary concentrating ability in either patient group.
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PMID:Nephrocalcinosis and its relationship to treatment of hereditary rickets. 282 87

MC 903 is a novel vitamin D analogue which has been tested for its effects on cell differentiation and cell proliferation in vitro using the human histiocytic lymphoma cell line U937, and on calcium metabolism in rats in vivo. In the present investigation MC 903 was compared to the natural metabolite of vitamin D3, 1 alpha,25-dihydroxycholecalciferol [1,25(OH)2D3] and to its synthetic analogue 1 alpha-hydroxycholecalciferol [1 alpha (OH)D3]. MC 903 was found to be a potent inducer of cell differentiation and to inhibit cell proliferation and DNA-synthesis in concentrations comparable to those observed with 1,25(OH)2D3. 1 alpha (OH)D3, which is only active after metabolic conversion to 1,25(OH)2D3, was more than 100 times less potent. Oral or intraperitoneal administration of MC 903 to rats showed that the compound was at least 100 times less active than 1,25(OH)2D3 and 1 alpha (OH)D3 in causing hypercalciuria, hypercalcemia and bone calcium mobilisation. The low vitamin D activity of MC 903 was further confirmed by administration of the compound to rachitic rats. The strong direct effects of MC 903 on cell proliferation and cell differentiation, coupled with its decreased activity as a classical vitamin D makes this compound an interesting candidate for studies in human proliferative disorders such as psoriasis.
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PMID:Effects of a novel vitamin D analogue MC903 on cell proliferation and differentiation in vitro and on calcium metabolism in vivo. 283 Aug 85

A familial observation of hypophosphatemic rickets with unusual inheritance and evolution, different from that of X linked hypophosphatemia, is reported. The mode of inheritance was autosomal dominant, a father and his son being affected. Severe early signs of rickets and delayed growth were present in both cases. Plasma 1,25 dihydroxyvitamin D and PTH levels were normal. There was no hypercalciuria. Complete cure of rickets and catch-up growth were obtained with the only treatment of vitamin D (40,000 U/day) in the father and of 1 alpha hydroxyvitamin D (1 microgram/day) in the son. This observation is quite similar to the 'autosomal hypophosphatemic bone disease' described by Scriver et al. It illustrates the heterogeneity of familial hypophosphatemia which presently includes 4 different physiopathological entities.
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PMID:[Scriver type autosomal hypophosphatemic rachitis: a family case]. 283 21

In the present study Farnolith (a granular powder consisting of different dietary fibres) was given to normals (n = 6), patients suffering from absorptive hypercalciuria type I (n = 6) and to one patient suffering from renal hypercalciuria. Farnolith binds calcium and reduces the calcium absorption from the intestine. In normals the urine- and serum parameters of calcium metabolism (total- and ionised calcium, parathyroid hormone and vitamin-D-metabolites) remained unchanged. In patients suffering from absorptive hypercalciuria type I a significant reduction of hypercalciuria was found; oxalic acid excretion had decreased as well. Lowered parathyroid hormone values returned to normal, vitamin-D-metabolites remained unaffected. In one patient suffering from renal hypercalciuria parathyroid hormone and 1,25-dihydroxy-vitamin D values increased, calcium excretion had not decreased, though. Our investigation shows that Farnolith is suitable for the treatment of absorptive hypercalciuria. Calcium homoeostasis is returned to normal by Farnolith, at the same time it does not produce secondary hyperoxaluria (as e.g. sodium cellulose phosphate). Patients with primary renal calcium loss should not be treated by Farnolith.
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PMID:Calcium metabolism in normal and in hypercalciuric patients on Farnolith, a dietary fibre preparation. 285 67

Hypercalcemia and hypercalciuria in sarcoidosis are thought to result from the endogenous overproduction of an active vitamin D metabolite. We employed primary cultures of pulmonary alveolar macrophages from two patients with biopsy-proven pulmonary sarcoidosis and a recent or current clinical abnormality in calcium metabolism to synthesize in vitro a 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]-like metabolite from 25-hydroxyvitamin D3 (25OHD3). The macrophage metabolite cochromatographed with [3H]1,25-(OH)2D3 on normal phase and reverse phase high performance liquid chromatography and was bound with high affinity by the chick intestinal receptor for 1,25-(OH)2D3. On UV spectroscopy, the metabolite possessed the carbon-5,7,10 (19) cis-triene chromophore characteristic of a vitamin D sterol. Electron impact mass spectrometry of trimethylsilyl ether derivatives of the metabolite revealed a mass fragmentation pattern similar to that of the trimethylsilyl ether derivative of authentic 1,25-(OH)2D3. The incubation of cultured macrophages from two patients with idiopathic pulmonary fibrosis and two with scleroderma with [3H]25OHD3 did not result in production of a metabolite with the chromatographic identity of 1,25-(OH)2D3. These data indicate that the metabolite of 25OHD3 synthesized by sarcoid macrophages in vitro is 1,25-(OH)2D3 and that the macrophage is a synthetic source of the sterol metabolite in sarcoidosis.
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PMID:Isolation and structural identification of 1,25-dihydroxyvitamin D3 produced by cultured alveolar macrophages in sarcoidosis. 298 38

The circadian rhythm of urinary total hydroxyproline (THP) excretion was determined in matched groups of ten male idiopathic calcium stoneformers and ten normal subjects in order to determine whether enhanced resorption of bone might contribute to hypercalciuria in these patients. THP increased progressively in normal subjects in successive eight-hour urine collections from period 1 (8 AM to 4 PM) to period 3 (12 midnight to 8 AM), the nocturnal high level in period 3 being significantly greater than in period 1 (P less than 0.01) and in period 2 (P less than 0.05). By contrast, no significant circadian rhythm was observed in THP excretion in the stoneformers. Their THP excretion was similar to that of normal subjects in period 3, but was significantly higher than that of normal subjects in period 1 (THP/creatinine ratio(mg/mg): 0.026 +/- 0.003 v 0.017 +/- 0.001; P less than 0.05. Indices of parathyroid hormone activity were not significantly different between stoneformers and normal subjects; mean serum 1,25(OH)2 vitamin D levels were higher in the stoneformers than the normal subjects (44 v 37 pg/mL) but the difference was not significant (P greater than 0.05). These studies suggest that increased bone turnover may contribute to hypercalciuria in these calcium stoneformers.
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PMID:Bone resorption and hypercalciuria in calcium stoneformers. 301 44


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