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)

This study confirms that medullary sponge kidney (MSK) has a good prognosis, but there is a considerable morbidity in patients with renal calcification; they suffer renal colic, ureteric obstruction, and frequently need operation. There is a high incidence of urinary infection in women. On follow-up, glomerular function is well maintained, although careful testing shows a mild depression of glomerular filtration rate in at least 40%. Proximal tubular function is normal, but abnormalities of distal tubular function are often seen: acidification defects occur in 24% and are associated with nephrocalcinosis, poor urine concentrating ability, and diminished glomerular function. Urine concentration defects occur in 73% and are probably secondary to nephrocalcinosis. Hypercalciuria was present in 19% and was not related to other defects.
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PMID:Medullary sponge kidney: abnormalities of renal tubular and glomerular function, and their relationship to clinical features. 60 Sep 68

Magnesium absorption was studied in the normal human jejunum and ileum by in vivo intestinal perfusion, using test solutions containing from 0 to 20 mM Mg (as MgCl2). As luminal Mg concentration was increased, the rate of absorption in the jejunum rose progressively with a tendency towards saturation at the higher concentrations. The kinetics and rates of Mg absorption in the ileum were comparable to those in the jejunum, with the exception that at higher luminal concentrations the ileal absorptive process was fully saturated. Using test solutions containing various combinations of Ca and Mg, we found that Ca had little or no influence on Mg absorption, even through Mg depressed Ca absorption to a modest extent. Patients with end-stage renal disease, who had a reduced rate of Ca absorption (presumably due to deficiency of 1,25-dihydroxycholecalciferol) were found to have a severe depression of Mg absorption. On the other hand, patients with absorptive hypercalciuria and nephrolithiasis, who had an increased rate of Ca absorption, were found to absorb Mg normally. These results suggest that Mg absorption in the human is mediated by a transport process different from that which facilitates Ca absorption, and that normal Mg absorption may be dependent on vitamin D. Our results do not establish whether or not the normal intestine can absorb Mg against an electrochemical gradient.
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PMID:Magnesium absorption in the human small intestine. Results in normal subjects, patients with chronic renal disease, and patients with absorptive hypercalciuria. 93 89

The effects of high calcium intake on vitamin D metabolism were investigated. To the normal diet of 14 healthy men, 2 g calcium were added daily for 6-7 weeks. The mean serum concentration of 25-hydroxyvitamin D3 increased from 73 +/- 7 to 94 +/- 6 nmol l-1 (P less than 0.05, Student's unpaired t-test; P less than 0.01, paired t-test) in the subjects receiving calcium, whereas there was only a minimal increase, from 67 +/- 5 to 71 +/- 4 nmol l-1 in a control group on a normal diet. At the end of the study the difference between the test group and the controls was highly significant (P less than 0.005). The calcium loading caused a statistically significant depression of the serum levels of 1,25-dihydroxyvitamin D. The results obtained are in agreement with previous studies in rats and indicate that calcium intake is of some importance for the serum level of 25-hydroxyvitamin D3. The findings are discussed in relation to our previous finding that there is a relationship between high 25-hydroxyvitamin D3 levels and hypercalciuria in renal-stone formers.
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PMID:Effect of calcium intake on serum levels of 25-hydroxyvitamin D3. 313 Feb 59

Monophotonic absorption densitometry of the forearm is an exact method for the evaluation of the bone mineralisation, provided the positioning of the forearm is strictly controlled. It is also able to demonstrate progressive enlargement of the bones with age, up until the ages of about 60 to 70 years. The measurements should be performed in two sites: diaphyseal (cortical bone) and epiphyseal (cortical and trabecular bone). The curves obtained from 1,011 controls are in agreement with the current state of knowledge concerning the variations in bone mass during life in both sexes. In women, the number of pregnancies has no influence on the mineralisation index (MI). The values obtained in 156 osteoporotic patients and in 53 subjects with idiopathic hypercalciuria were appreciably lower than those obtained in age-matched controls. In individual subjects, this method appears to be much more discrimination than the measurement of the trabecular bone volume (TBV) for the diagnosis of osteoporosis and no statistically significant correlation was observed between the MI and the TBV. In male controls, there was a depression of the mean curves around the age of 45 years in all four sites of measurement. This depression was also observed in male subjects with hypercalciuria. They correspond to the generations born between 1930 and 1940. The responsibility of a relative nutritional deficiency affecting growing boys during the 1939-45 war is proposed.
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PMID:[Bone densitometry by monochromatic photon absorption. Study of a normal population and values obtained in various pathological conditions]. 409 71

The renal handling of Ca in response to Na intake was evaluated in 12 patients with hypercalciuria and active kidney stone disease. There was no depression of urinary Ca excretion in response to the hypocalciuric effect of metolazone. Patients were hospitalized and their Ca and Na excretions measured while on a 190-mEq Na, 800-mg Ca, 1200-mg PO4- diet. These measurements were then repeated after Na intake decreased to 35 mEq/day while other variables, including diuretic dose and Ca intake, were unchanged. Two distinct responses were elicited by patients after Na restriction. In group I or the "responders" (n = 4), Ca excretion was reduced from 255 +/- 31 to 62 +/- 6 mg/24 hr. In the control group (n = 4), Ca excretion decreased from 95 +/- 8 to 57 +/- 11 mg/24 hr at similar levels of Na excretion. In group II or the "nonresponders" (n = 8), Ca excretion fell from 317 +/- 31 to 154 +/- 17 mg/24 hr when Na excretion was less than 50 mEq/24 hr. Metolazone with Na restriction normalized urine Ca excretion to the same order as in control subjects in group I. This is indicative of a mild Ca leak or a salt-sensitive leak. Despite diuretic and Na restriction most of the patients with hypercalciuria (group II) did not reabsorb Ca in a normal manner. This is indicative of a severe reabsorptive defect for Ca despite normal Na handling.
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PMID:Renal handling of sodium and calcium in hypercalciuria. 669 41

According to the Subcommittee on Classification and Definition of Sarcoidosis, it is a multisystem granulomatous disorder of unknown etiology. It most commonly affects young adults and presents most frequently with bilateral hilar adenopathy, pulmonary infiltrates, and skin or eye lesions. The diagnosis is established when clinical findings and appropriate x-ray findings are supported by tissue biopsy specimens in which noncaseating epithelioid cell granulomas are found. Immunologic features of the disease include depression of delayed hypersensitivity reactions, suggestive of impaired cell mediated immunity, and increased or abnormal immunoglobulin levels. Hypercalciuria may occur, with or without hypercalcemia. The course and prognosis of the disease correlate with the mode of onset. An acute onset in the presence of erythema nodosum indicates a self-limited course with spontaneous resolution, whereas an insidious onset may be followed by a relentless course. Corticosteroids are useful when therapy is required, as well as to suppress inflammation and the occurrence of granulomatous changes.
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PMID:Sarcoidosis. 675 25

We report 5 cases of renal calculi associated with incomplete type I renal tubular acidosis. The patients presented with a history of recurrent calculi and demonstrated bilateral calculi with corticomedullary junction calcification on x-ray. Stone analysis revealed primarily calcium phosphate stones and metabolic studies demonstrated hypercalciuria, mild depression of serum bicarbonate and inability to lower the pH of a fasting morning urine to less than 5.8. The 24-hour urinary citrate excretion was depressed markedly. The diagnosis was confirmed by an ammonium chloride loading test. Treatment consisted of alkalization of the patients, which corrects the hypercalciuria and increases the urinary citrate level and should decrease the tendency to form stones. The diagnosis of incomplete type I renal tubular acidosis should be considered in patients with recurrent renal calculi.
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PMID:Renal calculi associated with incomplete distal renal tubular acidosis. 717 46

Rapid immobilization after acute spinal cord injury (SCI) leads to increased bone resorption, net calcium efflux from the bone, hypercalciuria, depressed parathormone (PTH) and increased calcitonin release. However, the effects, if any, of long-standing SCI on calcium regulatory system is not well understood. We measured plasma concentrations of 25 hydroxy (OH) vitamin D, 1,25(OH)2 vitamin D (calcitriol), intact PTH molecule, calcitonin, ionized calcium [Ca++] and phosphorus in 40 clinically stable men with long-standing SCI of 3-year to 50-year duration (22 persons with paraplegia and 18 persons with quadriplegia). The results were compared with those obtained in 14 able-bodied control men. Plasma PTH concentration in the SCI group was significantly lower than that found in the able-bodied controls despite virtually identical concentrations of ionized calcium. Likewise, plasma calcitriol concentration in the SCI group was significantly lower than the value found in the able-bodied control group and lower in persons with quadriplegia than in those with paraplegia. In contrast, plasma calcitonin concentration in the quadriplegic group was significantly higher than that in persons with paraplegia and insignificantly higher than that in the control group. No significant difference was noted in serum ionized calcium between the study groups. PTH and calcitriol levels were positively related to one another (r = 0.35, p < .01) and negatively related to the level of injury (r = -0.43, p < .002 and r = -0.54, p < .001, respectively). In conclusion, long-standing SCI is associated with significant depression of calcitriol and PTH concentrations despite normal ionized calcium concentration.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Vitamin D, parathormone, and calcitonin profiles in persons with long-standing spinal cord injury. 802 22

At the origin, idiopathic hypercalciuria has been described as a syndrome consisting of normocalcemia, low plasma phosphate levels and abnormally high urinary calcium excretion. The cause of this syndrome was subject to many investigations throughout the years. Two main pathophysiologic hypotheses have been proposed: a) primary intestinal hyperabsorption of calcium, leading to depression of parathyroid hormone (PTH) secretion ("absorptive" hypercalciuria); and b) primary renal tubular leak of calcium which stimulates PTH secretion (secondary hyperparathyroidism). Most of the published studies indicate that intestinal hyperabsorption of calcium with subsequent relative hypoparathyroidism is the primary event causing idiopathic hypercalciuria, and that this occurs as a consequence of increased production of 1,25(OH)2-vitamin D3 (calcitriol). Fasting hypercalciuria, originally taken as evidence for a "renal leak" of calcium, appears to be, at least in part, the consequence of relative hypoparathyroidism.
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PMID:The tale of parathyroid function in idiopathic hypercalciuria. 831 9

In general, bone loss from glucocorticoid treatment occurs rapidly within the first 6 months of therapy. Glucocorticoids alter bone metabolism by multiple pathways; however, the bone loss is greatest in areas rich in trabecular bone. Preventive measures should be initiated early. It is the author's opinion that all subjects initiating treatment with prednisone at 7.5 mg or greater require calcium supplementation (diet plus supplement) at a dose of 1500 mg and vitamin D at a dose of 400 to 800 IU/d. If the patient is going to remain on this dose of glucocorticoid for more than 4 weeks, an antiresorptive agent should be started (e.g., estrogen, bisphosphonate, raloxifene). If a patient has established osteoporosis and is either initiating glucocorticoid therapy or is chronically treated with prednisone at 5 mg d or greater in addition to calcium and vitamin D supplementation, a potent antiresorptive agent (bisphosphonate) should be started. A bone mineral density measurement of either the lumbar spine or the hip may be helpful is assessing an individual's risk of osteoporosis, may improve compliance with treatment, and can be used to monitor the efficacy of the prescribed therapy. There is no reason to withhold treatment for glucocorticoid-induced bone loss until a bone mass measurement is taken, however. In motivated patients, a weight-bearing and resistance exercise program should be prescribed to help retain muscle strength and prevent depression. If hypercalciuria develops with glucocorticoid use, either thiazide diuretics or sodium restriction may be helpful. In patients who continue to lose bone or experience fracture's despite antiresorptive therapy while on glucocorticoids, bone-building anabolic agents (e.g., hPTH 1-34 or PTH 1-84) may be available someday soon.
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PMID:An update on glucocorticoid-induced osteoporosis. 1128 98


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