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)

Ketoconazole was used to probe the pathogenetic importance of the serum 1,25-dihydroxyvitamin D [1,25-(OH)2D] concentration in 19 patients with well characterized absorptive hypercalciuria (AH). Patients were studied while receiving a constant metabolic diet before and after 2 weeks of ketoconazole administration (600 mg daily). Twelve of the patients were classified as ketoconazole responders, because in conjunction with a reduction of serum 1,25-(OH)2D from 113 +/- 36 to 70 +/- 26 pmol/L, intestinal 47Ca absorption decreased from 76.3 +/- 8.1% to 61.9 +/- 7.7%, and 24-h urinary Ca excretion declined from 7.6 +/- 1.4 to 5.7 +/- 1.1 mmol (P < 0.001 each). In these patients, intestinal 47Ca absorption was directly correlated with serum 1,25-(OH)2D levels and 24-h Ca excretion. In another group of 7 patients, termed ketoconazole nonresponders, despite reduction of 1,25-(OH)2D from 122 +/- 36 to 84 +/- 17 pmol/L (P = 0.015), there was no significant change in intestinal Ca absorption (76.0 +/- 8.2% to 72.1 +/- 10.6%) or 24-h urinary Ca excretion (7.3 +/- 1.3 to 7.2 +/- 1.0 mmol). In these patients, neither intestinal Ca absorption nor urinary Ca excretion was correlated with serum 1,25-(OH)2D levels. It, thus, appears that AH is a heterogeneous disorder comprised of both vitamin D-dependent and vitamin D-independent subsets. Although useful to probe the pathogenesis of AH, chronic treatment with ketoconazole is not recommended because of its generalized effects in inhibiting steroid synthesis.
J Clin Endocrinol Metab 1992 Dec
PMID:Use of ketoconazole to probe the pathogenetic importance of 1,25-dihydroxyvitamin D in absorptive hypercalciuria. 146 46

Dual-energy x-ray absorptiometry and single-photon absorptiometry were used to determine bone density at the lumbar spine and radial shaft in 62 patients with absorptive hypercalciuria, 27 patients with fasting hypercalciuria, and 31 nonhypercalciuric stone formers. Lumbar bone density was significantly lower in patients with absorptive (-10%) as well as in those with fasting hypercalciuria (-12%), with 74 and 92% of patients displaying values below the normal mean, whereas only 48% of the nonhypercalciuric stone formers had bone density values below the normal mean. In contrast, radial bone density was similar in all three groups of renal stone formers investigated. The comparison of urinary chemistry in patients with absorptive hypercalciuria and low normal bone density compared to those with high normal bone density showed a significantly increased 24 h urinary calcium excretion on random diet and a trend toward a higher 24 h urinary uric acid excretion and a higher body mass index in patients with low normal bone density. Moreover, among the patients with absorptive hypercalciuria we found a statistically significant correlation between the spinal bone density and the 24 h sodium and sulfate excretion and the urinary pH. These results gave evidence for an additional role of environmental factors (sodium and animal proteins) in the pathogenesis of bone loss in absorptive hypercalciuria. In conclusion, our data suggest an osteopenia of trabecular-rich bone tissues in patients with fasting and absorptive hypercalciurias.
J Bone Miner Res 1992 Dec
PMID:Reduced vertebral bone density in hypercalciuric nephrolithiasis. 148 24

An open and controlled prospective study was used to assess the preventive efficiency of 1 alpha-hydroxy vitamin D3 (1 alpha (OH) Vit. D3) on post-menopausal vertebral bone loss. Of the 36 patients included in the study, 25 completed two years of treatment with 1 microgram/day of 1 alpha (OH) Vit. D3 and 500 mg of calcium. The vertebral bone mineral density measured by dual photon absorptiometry did not vary in the treated group, whereas it decreased significantly in the control group at the end of the 2 years. At two years, withdrawal of treatment led to a significant bone loss, whereas bone mass remained stable in a subgroup of patients who underwent a third year of treatment with 1 alpha (OH) Vit. D3. Overall, tolerance was satisfactory. However, urinary calcium increased significantly during treatment and one third of the patients developed hypercalciuria > or = 7.5 mmoles/24 h. No variation in either serum calcium or creatinine levels was noted. These results indicate that 1 alpha (OH) Vit. D3 could be useful in preventing post-menopausal bone loss provided it was complemented by regular monitoring of urinary calcium excretion.
Clin Rheumatol 1992 Dec
PMID:Prevention of post-menopausal bone loss with 1 alpha-hydroxy vitamin D3. A three-year prospective study. 148 38

We describe an adult patient who developed persistent hypercalcemia while bedridden for more than three months with pancreatitis and sepsis. On the basis of hypercalciuria, suppressed serum intact PTH, suppressed serum 1,25-dihydroxy vitamin D3 and no clinical evidence of malignancy, the diagnosis of immobilization hypercalcemia was established His hypercalcemia improved during treatment with saline, calcitonin and/or etidronate. With active mobilization and weight-bearing exercises, serum calcium finally normalized. We discuss clinical and laboratory features as well as current modalities of treatment of this rare form of hypercalcemia in adults.
J S C Med Assoc 1992 Dec
PMID:Immobilization hypercalcemia in an adult patient with pancreatitis and sepsis: case report. 148 89

The geminal bisphosphonates are a new class of drugs characterised by a P-C-P bond. Consequently, they are analogues of pyrophosphate, but are resistant to chemical and enzymatic hydrolysis. The bisphosphonates bind strongly to hydroxyapatite crystals and inhibit their formation and dissolution. This physicochemical effect leads in vivo to the prevention of soft tissue calcification and, in some instances, inhibition of normal calcification. The main effect is to inhibit bone resorption, but in contrast to the effect on mineralisation, the mechanism involved is cellular. These various effects vary greatly according to the structure of the individual bisphosphonate. The half-life of circulating bisphosphonates is very brief, in the order of minutes to hours. 20% to 50% of a given dose is taken up by the skeleton, the rest being excreted in the urine. The half-life in bone is far longer and depends upon the turnover rate of the skeleton itself. Bisphosphonates are very well tolerated; the relatively few adverse events that have been associated with their use are specific for each compound. Bisphosphonates have been used to treat various clinical conditions, namely ectopic calcification, ectopic bone formation, Paget's disease, osteoporosis and increased osteolysis of malignant origin. The three compounds commercially available for use in tumour-induced bone disease are in order of increasing potency, etidronate, clodronate and pamidronate. Most data have been obtained with the latter two agents. By inhibiting bone resorption, they correct hypercalcaemia and hypercalciuria, reduce pain, the occurrence of fractures, as well as the development of new osteolytic lesions, and in consequence improve the quality of life. In view of these actions, of their excellent tolerability and of the fact that they are active for relatively long periods, these compounds are, after rehydration, the drugs of choice in tumour-induced bone disease and an excellent auxiliary to the drugs used in oncology.
Drugs 1991 Dec
PMID:Bisphosphonates. Pharmacology and use in the treatment of tumour-induced hypercalcaemic and metastatic bone disease. 172 40

Bone mineral density (BMD) of the 3rd lumbar spine was measured by dual photon absorptiometry (DPA) in 8 patients with primary hyperparathyroidism (PHP) and 39 patients with idiopathic urolithiasis (IU). Of the patients, 15 were classified into idiopathic hypercalciuria (IH) which were further classified into 2 types of IH--renal hypercalciuria (RH) and absorptive hypercalciuria (AH)--by Ca restriction and load test. BMD of the IH patients tended to be lower than patients with normocalciuria, but significantly higher than the PHP patients. BMD of the RH patients was significantly lower than the AH patients. In conclusion, DPA may be a simple method for classifying the types of idiopathic hypercalciuria.
Nihon Hinyokika Gakkai Zasshi 1991 Dec
PMID:[Bone mineral densitometry by dual photon absorptiometry in patients with urolithiasis--on the possibility of the differential diagnosis of idiopathic hypercalciuria]. 177 98

In-vivo microperfusion was used to localize the reabsorptive defect responsible for the hypercalciuria of diabetes mellitus and to investigate possible causative factors. Unidirectional proximal calcium absorption was not significantly different in rats made diabetic with streptozotocin compared with controls, providing evidence against the involvement of this nephron segment in the phenomenon. Calcium absorption by the loop of Henle, was however, significantly (P less than 0.01) lower in diabetic animals (32.1 +/- 1.2 vs 40.4 +/- 0.6 pmol/min). Based on our knowledge of calcium movements within the loop, it is likely that the reabsorptive defect residues within the thick ascending limb. The calcium lesion was found to be independent of acute changes in intraluminal glucose concentration and could not be corrected by acute insulin treatment. The study also provides new information on the relationship between intratubular glucose and fluid movements in the rat nephron. In diabetic rats a proximal perfusate containing 30 mmol glucose/l resulted in fluid absorption comparable with that seen in control rats perfused with 5 mmol glucose/l. However, intraluminal glucose had a stimulatory effect on fluid absorption in the loop of Henle of diabetic rats (10.7 +/- 0.5 vs 7.9 +/- 0.4 nl/min; P less than 0.01).
J Endocrinol 1991 Dec
PMID:Calcium transport in the proximal convoluted tubule and loop of Henle of rats made diabetic with streptozotocin. 178 84

A Ca kinetic study with a four-compartment model being fitted to radioisotope and balance data using the CONSAM (conversational, simulation, analysis, and modeling) computer program was conducted to examine the effects of dietary cation-anion balance, calculated as milliequivalents [(Na + K] - (Cl + S)]. Twelve crossbred wethers were used as eucalcemic control (period 1); then Ca loss during lactation was simulated by continuous infusion of ethylene glycol tetraacetate (period 2). Dietary cation-anion balance was manipulated by supplementation of various mineral salts and was +339, +35, and -127 meq of kg DM-1 during period 1 and +429, +68, and -147 meq of kg DM-1 during period 2 for control and two treatments, respectively. Animals responded to the simulated lactational Ca loss (period 2) by increasing true intestinal absorption of Ca and bone resorption and by reducing Ca accretion by bone. No difference was observed in concentration of total Ca in plasma, but treatments produced increased concentration of plasma ionized Ca during both periods. Both treatments produced hypercalciuria during both periods, and the lowest cation-anion balance increased true intestinal absorption of Ca and reduced bone accretion during period 2. The size of total exchangeable Ca pool did not differ between treatments or periods, but amount of Ca movement between the pools increased with the intermediate cation-anion balance during period 1 and with both treatments during period 2 compared with control. These results indicated that feeding reduced cation-anion balance diets increased Ca flux through the exchangeable Ca pool with no changes in the size of the pool, particularly when Ca demand was increased.
J Dairy Sci 1991 Dec
PMID:Effects of reducing dietary cation-anion balance on calcium kinetics in sheep. 178 93

To test the hypothesis that hyperfiltration in essential hypertension is linked to alterations in calcium metabolism, we studied the relationship between urinary calcium excretion and glomerular filtration rate (GFR, creatinine clearance) in 38 untreated essential hypertensives on a free diet. We also studied the influence of changes in calcium intake on GFR in 30 essential hypertensives (15 with well-defined hypercalciuria and 15 with normal urinary calcium excretion) and in 11 normotensive healthy subjects. In the patients on a free diet, urinary calcium excretion was directly and independently related to GFR (r = 0.56, P less than .001), while serum calcium showed an opposite trend (r = -0.27, P = .12). In patients on fixed calcium diets, GFR was significantly higher (P = .008) at low calcium intake (115 +/- 31 mL/min/1.73 m2) than at high calcium intake (98 +/- 22 mL/min/1.73 m2). Further analysis showed that the hyperfiltering effect of low calcium almost exclusively occurred in hypercalciuric patients and in hypertensive women. In hypercalciuric hypertensives there was a highly significant inverse correlation between GFR and serum calcium (r = -0.51, P = .004) and a similar correlation between GFR and plasma renin activity (r = -0.70, P = .003) in the high calcium phase of the study. Changes in calcium intake had no influence on GFR in normal subjects (Low Ca 103 +/- 22 mL/min/1.73 M2, High Ca 110 +/- 23 mL/min/1.73 m2). The data indicate that alterations in calcium metabolism interfere to an important extent with mechanism(s) regulating GFR in essential hypertension.
Am J Hypertens 1991 Dec
PMID:Hyperfiltration and calcium metabolism in essential hypertension. 181 51

No information exists in the literature about the optimal time for metabolic evaluation of stone patients in relation to extracorporeal shock wave lithotripsy (ESWL) treatment. It is uncertain whether the presence of a stone, ESWL treatment itself or subsequent colic episodes influence the urinary risk factors. A prospective study was performed to determine the optimal period for metabolic evaluation. Two 24-hour urine samples were collected directly before, and 1 week, 1 month and 3 months after therapy in an outpatient setting and tested for total volume, calcium, uric acid, oxalate, citrate and creatinine levels. A total of 66 patients was available for evaluation. Comparison of the 4 subsequent collecting periods showed no statistically significant differences in the excretion values. Also, in subgroups of patients with colic (16%), on a calcium oxalate restricted diet (12%) and with repeated treatments within 3 months (33%) no differences were noted. This means that the presence of a stone, treatment itself or subsequent colic episodes have no adverse effect on the urinary risk factors. For practical reasons metabolic evaluation directly before ESWL treatment seems most attractive. In the pre-ESWL samples hypercalciuria (greater than 7.5 mmol./24 hours), hyperuricosuria (greater than 6 mmol./24 hours), hyperoxaluria (greater than 0.5 mmol./24 hours) and hypocitraturia (less than 2 mmol./24 hours) were found in 31%, 12%, 18% and 27%, respectively, of the patients. It is concluded that metabolic evaluation before ESWL is practical, applicable and reliable.
J Urol 1991 Dec
PMID:Metabolic evaluation in stone patients in relation to extracorporeal shock wave lithotripsy treatment. 194 22


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