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

A patient with pseudoxanthoma elasticum was documented to be hyperphosphatemic and mildly hypercalcemic for six years. Complications included metastatic calcification, absorptive hypercalciuria, and renal insufficiency. The 1,25-dihydroxyvitamin D value was elevated, despite normal serum parathyroid hormone values, high serum phosphate levels, and renal insufficiency. Either increased dietary calcium or prednisone seemed to suppress the 1,25-dihydroxyvitamin D value. Nephrolithiasis or abnormalities suggestive of pseudoxanthoma elasticum occurred in the patient's father, daughter, and several siblings, suggesting a distinct familial syndrome in which connective tissue changes are accompanied by abnormalities of phosphorus and vitamin D metabolism that may resemble those in the syndrome of familial tumoral calcinosis. Nine similar cases were described before 1970.
 ...
PMID:Heritable syndrome of pseudoxanthoma elasticum with abnormal phosphorus and vitamin D metabolism. 333 71

Enhanced calcium and phosphorus retention was achieved in 16 very low birth weight infants (birth weight 1117 +/- 42 g, gestation 29 +/- 0.2 weeks) fed a preparation of fortified human milk augmented with calcium lactate and monobasic and dibasic phosphate salts. Measurements of growth and macronutrient utilization were similar to those obtained in a previous study of infants fed a preparation of fortified human milk that contained lower levels of calcium and phosphorus. However, unlike the relative hypophosphatemia, hypophosphaturia, and hypercalciuria noted in the infants in our earlier study, normal serum and urine phosphorus and urine calcium values were observed in this study. Postnatal calcium and phosphorus retentions correlated significantly with respective intakes, the absorption of fat, and the retention of nitrogen. The relationships among calcium and phosphorus intake and retention predict that 160 mg/kg/d and 94 mg/kg/d, respectively, must be fed to achieve retention equivalent to intrauterine estimates. Although postnatal retention of calcium and phosphorus may be increased to levels accumulated by the fetus, technical considerations for the preparation of a formula with sufficiently high levels of calcium and phosphorus must be resolved.
 ...
PMID:Improved mineral balance in very low birth weight infants fed fortified human milk. 334 87

Effects of fixed cation-anion balance on acid-base status and calcium and phosphorus balances were examined. Pregnant and lactating goats were fed a diet of alfalfa hay, concentrate and minerals to vary the cation-anion balance [meq sodium (Na) + meq potassium (K)-meq chloride (Cl)]/100 g diet dry matter (DM) over the range found in ruminant feeds. Small but significant effects on ruminal pH, fermentation and dilution rate were observed. Metabolic acid-base status of pregnant and lactating goats was normal when (Na + K - Cl) balance was 40 to 50 meq/100 g DM. The other treatments drastically altered plasma electrolyte concentrations, causing metabolic acid-base disturbances and profound changes in calcium and phosphorus metabolism. Subclinical hypernatremic, hypochloremic metabolic alkalosis was induced by a dietary fixed cation excess (Na + K - Cl) of greater than 85 meq/100 g DM (typical of buffered, alfalfa diets) and caused hypocalciuria, diminished calcium and phosphorus absorption, and possibly diminished dietary calcium absorption and resorption of calcium from bone. Subclinical hyperchloremic, hyponatremic metabolic acidosis from a diminished dietary fixed cation-anion balance (Na + K - Cl) of less than 10 meq/100 g DM (typical of nonbuffered corn silage or grain diets) caused hypercalciuria, enhanced calcium and phosphorus absorption and apparently enhanced calcium resorption from bone. Apparent effects on absorption and resorption depended on calcium and phosphorus intakes. Alterations in goats performance were not demonstrable. Dietary excesses of fixed cations over anions (meq Na + K - Cl/100 g diet DM greater than 50) cause metabolic alkalosis in ruminants, whereas fixed anion excesses (meq Na + K - Cl/100 g diet DM less than 40) cause metabolic acidosis. Content of electrolytes in diets should be reported in all nutrition trials with ruminants for assessment of metabolic acid-base status.
 ...
PMID:Characterization of acid-base disturbances and effects on calcium and phosphorus balances of dietary fixed ions in pregnant or lactating does. 336 4

Dihydrotachysterol (DHT2) has been a safe and effective treatment for hypocalcemic disorders for many years, but few assays for quantitation of DHT2 have been developed. Thus little is known about its pharmacokinetics. The 2-fold purpose of this study was 1) to develop a practical method for quantitating DHT2 after oral dosing in normal subjects, and 2) to assess changes in serum DHT2 levels and calcium and phosphorus metabolism after DHT2 administration for 8 days. Peak serum DHT2 levels in six normal subjects, assayed by high performance liquid chromatography were achieved 4 h after administration of 0.4-0.8 mg DHT2; at 24 h, levels had declined by 70% whether DHT2 had been given for 1 or 8 days. These data indicate that a standard approach is needed to interpret the results of serum DHT2 measurements in treated patients. Interfering substances were detected in lipemic serum. The major biological effects of DHT2 administration were hypercalciuria in two subjects and a fall in serum 1,25-dihydroxyvitamin D[1,25-(OH)2D] levels, including free levels when measured, in all subjects. Possible explanations for this fall in serum 1,25-(OH)2D levels include decreased 1,25-(OH)2D production because of competition for the 1 alpha-hydroxylase enzyme by a metabolite(s) of DHT or increased metabolic clearance of 1,25-(OH)2D.
 ...
PMID:Serum dihydrotachysterol levels and biological action in normal man. 337 33

Dietary protein exerts a significant calciuretic effect. A twofold increase in protein at constant levels of calcium and phosphorus intakes causes a 50% increase in urinary calcium. The protein-induced hypercalciuria results primarily from decreased fractional renal tubular reabsorption of calcium associated with catabolism of excess sulfur amino acids and the resultant urinary excretion of acid and sulfate. A protein-induced elevation in glomerular filtration rate also contributes to the calciuresis. Dietary phosphorus also modifies the calciuretic effect of proteins, as it increases renal tubular reabsorption of calcium and thereby exerts a hypocalciuretic effect. Consequently, a soy-based diet was able to maintain calcium balance at a calcium intake of 457 mg/day in spite of a protein intake of 90 g, presumably due to the lower level of sulfur amino acids in the soy diet and to the 1450 mg phosphorus which accompanied the soy protein.
 ...
PMID:Calcium utilization: effect of varying level and source of dietary protein. 341 94

The role of hypercalciuria and hyperphosphaturia in the growth retardation of children with diabetes mellitus was investigated in 157 children with diabetes whose mean height was less than that of 37 nondiabetic siblings of similar age (P less than .025). Hyperglycemia, hypercalciuria, and hyperphosphaturia were assessed coincident with the height measurement of each child in a cross-sectional survey. The distribution of height percentiles of the children with diabetes was skewed to the left with 61% at or below the 50th percentile. Eleven percent of the insulin-dependent children with diabetes mellitus were shorter than would be anticipated by a normal distribution of the 157 children. The duration of diabetes (hyperglycemia) had the greatest influence upon the children's height. Children with diabetes were shorter than the nondiabetic subjects by the fourth year of hyperglycemia, and this difference in height became statistically significant after 7 years or more of diabetes. The degree of hypercalciuria and hyperphosphaturia was more closely associated with reduced height in children with diabetes than was the degree of hyperglycemia, although the renal wastage of calcium and phosphorus seemed to be the result of glucosuria. Because hypercalciuria and hyperphosphaturia impair growth in nondiabetic children, they may also play an important role in the poor growth of children with diabetes mellitus.
 ...
PMID:Hypercalciuria, hyperphosphaturia, and growth retardation in children with diabetes mellitus. 348 37

Calcium and phosphorus retention was evaluated in 13 very low birth weight infants who were fed an experimental formula designed to deliver quantities of calcium and phosphorus sufficient to meet the intrauterine accretion rates for these minerals. Retention of calcium and phosphorus in slight excess of these rates was achieved without any apparent difficulties for the infants. Biochemical measurements demonstrated normal serum calcium (9.8 +/- 8 mg/dL) and alkaline phosphatase (242 +/- 51.6 IU) values. However, there was evidence of high tubular reabsorption of phosphate (98.1% +/- 3.3%), hypercalciuria (7.2 +/- 3.8 mg/kg/d), and a relatively low serum phosphorus concentration (5.7 +/- 0.6 mg/dL). This biochemical picture is similar to that seen in phosphorus deficiency except for the low alkaline phosphatase activity. The latter finding, in concert with the high retention of calcium and phosphorus in these balance studies, makes such a diagnosis unlikely. We speculate that this biochemical picture is the result of an inappropriately high calcium/phosphorus ratio.
 ...
PMID:Achievement of in utero retention of calcium and phosphorus accompanied by high calcium excretion in very low birth weight infants fed a fortified formula. 355 9

1,25 dihydroxyvitamin D (1,25(OH)2 D) is the active metabolite of vitamin D and has an essential role in bony metabolism on the regulation of the calcium-phosphorus balance. The circulating level of 1,2(OH)2 D is normally between 25 and 45 pg/ml. Isolation of the fraction to be titrated requires sophisticated purification techniques using high performance chromatography (HPLC). In osteomalacia secondary to a deficiency the mean level of 1,25(OH)2 D is low (14.1 +/- 6.9 pg/ml) because of substratum deficiency. Administration of vitamin D supplements is quickly followed by a supraphysiological increase of the level of active metabolite. The role of the parathyroid hormone on the activity of 1-hydroxylase is illustrated by the results of the titration in parathyroid dysfunctions: decrease of the mean level in hypoparathyroidism (18 +/- 6.9 pg/ml), and on the contrary, a significant increase in hyperparathyroidism (56.6 +/- 15.4 pg/ml) despite of a spread of the individual values. In 18 cases of idiopathic hypercalciuria, we have only observed an increase of 1,25(OH)2 D level, in two cases. Titration of 1,25(OH)2 D complements the calcium-phosphorus evaluation to precise the physiopathogenic mechanism of the disorders observed in various diseases. Its interpretation requires the joint measurement of the substratum level, 25-hydroxyvitamin D, and the evaluation of the parathyroid function.
 ...
PMID:[Serum concentrations of 1,25-dihydroxyvitamin D in cases of osteomalacia, parathyroid dysfunction and idiopathic hypercalciuria]. 356 83

Two patients with extensive tumoral calcinosis were treated with aluminium hydroxide. Initial metabolic studies showed positive calcium and phosphorus balances which became negative with aluminium hydroxide treatment. One subject, who had renal impairment, developed transient hypercalcaemia, parathyroid suppression, low levels of 1,25-dihydroxyvitamin D and calcium malabsorption during treatment with aluminium hydroxide. The second patient developed calcium malabsorption due to vitamin D deficiency. When she was replete with vitamin D there were supranormal levels of 1,25-(OH)2D in the serum and enhanced calcium absorption during treatment with aluminium hydroxide. Both subjects developed hypercalciuria and there was dissolution of many of the calcific tumours. The patient with renal impairment accumulated aluminium in the bone.
 ...
PMID:Tumoral calcinosis: clinical and metabolic response to phosphorus deprivation. 365 64

1. Vitamin-D-deficient pigs were fed on a phytate-phosphorus diet and treated with vitamin D3 (+D) to examine the time-course of adaptative changes in plasma minerals, vitamin D metabolites, parathyroid hormone (PTH) and calcium balance and intestinal Ca-binding protein (CaBP). 2. The 5-week vitamin D repletion (25 micrograms cholecalciferol/kg diet) regimen restored plasma Ca, P and alkaline phosphatase (EC 3.1.3.1) to normal, decreased PTH and markedly and rapidly increased plasma 25-hydroxycholecalciferol (25-OHD, sevenfold after 4 d) and 1,25-dihydroxycholecalciferol (1, 25(OH)2D3, 1.8-fold after 4 d). 3. CaBP concentrations were markedly elevated all along the digestive tract, especially in the distal regions. 4. Ca absorption and retention were enhanced (fourfold and sixfold respectively) by the +D diet. 5. The improved Ca absorption, coupled with increased CaBP and 1,25(OH)2D3 levels, suggest that vitamin D metabolism in phytate-P-fed pigs is sensitive to the depressed Ca availability due to phytate feeding. It also indicates that CaBP may play an important role in the adaptation of Ca absorption. 6. Persistent hypercalciuria indicates that mineral metabolism was still affected by the phytate nature of the dietary P in spite of the vitamin D treatment.
 ...
PMID:Effects of vitamin D on calcium regulation in vitamin-D-deficient pigs given a phytate-phosphorus diet. 367 38


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>