Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020437 (hypercalcemia)
 10,293 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Seventeen undialysed adult patients with chronic renal failure took part in a controlled study of the effects of 1,25(OH)2D3 and D3. After a 6-month observation period the patients were allocated at random to two groups for 6 months of treatment with either 1,25(OH)2D3 (mean dose 0.5 microgram daily) or D3 (dose 100 microgram daily). The treatment was then discontinued and the patients were studied for a further 3 months. In the 1,25(OH)2D3 group the mean serum concentration of 1,25(OH)2D rose significantly during treatment, whereas serum concentratins of 25OHD and 24,25(OH)2D remained unchanged. In the D3 group there was a highly significant increase in serum concentrations of 25OHD and 24,25(OH)2D, whereas serum 1,25(OH)2D remained unchanged. There was a significant fall in serum iPTH in both treatment groups. This fall was unrelated to serum calcium in the D3 group unlike the findings in the 1,25(OH)2D3 group. The data support previous experimental evidence that serum iPTH can be suppressed by 24,25(OH)2D3 and suggest that this analogue may be of clinical importance in the treatment of chronic renal failure without inducing hypercalcaemia.
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PMID:A possible direct effect of 24,25-dihydroxycholecalciferol on the parathyroid gland in patients with chronic renal failure. 627 28

Experimental chronic renal failure (CRF) in rats gave rise to azotemia, hyperphosphatemia, reduction in the proportion of the diaphyses, decrease in them of calcium, phosphorus and hydroxyproline, and to the lowering of the calcium content in the epiphyses. Administration to the animals of 0.025 microgram of 1,25-dioxycholecalciferol (1,25(OH)2D3) a day did not make the indicators under consideration return to normal. At the same time 1,25(OH)2D3 enhanced the degree of hyperphosphatemia and demineralization of the epiphyses, provoked moderate hypercalcemia and dramatically enhanced calcinosis in the aorta and in the remainder of the kidney. Administration of 24,25-dioxycholecalciferol (24,25(OH)2D3) in a dose of 0.25 microgram made the majority of the indicators return to normal, increasing the proportion of the diaphyses and the content in them of calcium and phosphorus, reducing the blood phosphorus content and the degree of azotemia. Furthermore, 24,25(OH)2D3 raised the collagen content in the diaphyses and epiphyses. A higher dose of 24,25(OH)2D3 (1.25 microgram) did not appear more effective. In none the doses applied, 24,25(OH)2D3 produced hypercalcemia or calcinosis. Combination of 1,25(OH)2D3 in a dose of 0,025 microgram and 24,25(OH)2D3 in a dose of 1,25 microgram slightly reduced the hypercalcemic, hyperphosphatemic and calcinosis-inducing effects of 1,25(OH)2D3, completely prevented osteoporotic alterations in the diaphyses, but enhanced the demineralization in the epiphyses, which may point to the advisability of reducing the doses of these metabolites on combined use. The data obtained indicate that 24,25(OH)2D3 is a more effective and safer agent for correcting the disturbances of the phosphorus-calcium metabolism and osseous lesions in CRF than 1,25(OH)2D3.
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PMID:[Effect of 24,25-dioxycholecalciferol on calcium-phosphorus metabolism and bone tissue in rats with experimental renal failure]. 633 22

Intense diffuse uptake of Tc-99m-labeled methylene diphosphonate was seen in both lungs of a patient submitted to surgery for a primary parathyroid adenoma. Five scans performed over the 3 yr following the operation showed persistence of lung uptake despite restoration of normal blood calcium concentration. Mild chronic renal failure caused by the hypercalcemia also persisted postoperatively. The present case confirms that pulmonary uptake of bone tracer can occur asymptomatically when both hypercalcemia and renal failure are present. Lung uptake of a bone tracer probably reflects tissue deposition of hydroxyapatite rather than of amorphous structures. Correction of the hypercalcemia failed to resolve the abnormal scan pictures.
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PMID:Pulmonary uptake of Tc-99m-Labeled methylene diphosphonate in a patient with a parathyroid adenoma. 645 36

Over a period of six months all reports in the South Tees Health District of serum calcium levels greater than 2.70 mmol/l were extracted and patient records examined to establish the associated diseases and patterns of management. A total of 235 reports were evaluated, and after exclusion of doubtful cases 196 patients were included in the study. No cause had been identified in 57 (29%). Many of these were elderly females in whom hypercalcaemia may have been due to primary hyperparathyroidism, but parathyroid hormone levels had not been measured. Of those in whom a diagnosis had been made, 62 (45%) were associated with malignancy and 50 (36%) with chronic renal failure. 72% of cases of hypercalcaemia reported to general practitioners and 13% of those reported to hospital doctors were not investigated further. Despite the inclusion of serum calcium estimation on routine biochemical profiles, many cases of hypercalcaemia are being ignored or not investigated further. The study emphasizes the need for a reliable screening test for primary hyperparathyroidism.
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PMID:Hypercalcaemia in Cleveland: a hospital-based survey. 648 55

A 49-year-old woman at recent climacterium was admitted to our hospital for a dyspeptic-type symptomatology, weight loss, bone pain, moderate polyuric-polydipsic syndrome and in a marked astheno-depressive state. Paraclinical explorations revealed constant hypercalcemia with hypophosphoremia, calciuria, chronic renal failure in the polyuric phase with retention of nitric bases. X-ray films showed diffuse osteoporosis, right nephrocalcinosis and diffuse calcifications of the galactophorous ducts in both breasts. Computerized tomography revealed and surgery confirmed the presence of tumoral tissues on the anterior aspect of the trachea. Histopathologic examination revealed a parathyroid adenoma.
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PMID:Primary hyperparathyroidism associated with galactophorous ducts calcification. 649 88

During a four-year period, 27 patients underwent total parathyroidectomy with autotransplantation of parathyroid tissue to the forearm. In order to minimize the risk of persistent or recurrent hyperparathyroidism (HPT), a routine thymic resection and a wide excision of fat tissue around the parathyroids was performed to ensure excision of possible supernumerary glands or rudimentary parathyroid tissue. The indications for operation were HPT secondary to chronic renal failure in 24 patients (22 of whom had hypercalcaemia) and persistent or recurrent primary HPT in 2 cases. One further patient, who had a multiple endocrine neoplasia syndrome type I, underwent this procedure at the primary parathyroid operation. Preoperative hypercalcaemia was reversed in all patients but three during the first postoperative days, concomitantly with a fall in the parathyroid hormone (PTH) level. Fourteen patients showed marked hypocalcaemia postoperatively, necessitating calcium or vitamin D supplementation. This medication could later be discontinued in all of them. Thirteen patients, including two of those with primary HPT, never required any supplemental therapy. Survival of the grafts was documented by several observations. In all patients normal serum calcium values were being maintained without supplemental therapy at follow-up. During induced hypocalcaemia a PTH secretory response was demonstrated in all eight studied patients with a gradient between the grafted and non-grafted arm. In two patients in whom the grafts were examined histologically 19 and 28 months after the transplantation, viable parathyroid tissue was observed. In the initial part of the study excised tissue was cryopreserved. Since persistent hypocalcaemia did not occur in our patients, we have now abandoned this safety precaution. Thus, total parathyroidectomy with autotransplantation of parathyroid tissue is a valuable method for restoring long-term parathyroid function in patients with secondary HPT and uraemia. It also appears of value in selected cases of primary HPT.
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PMID:Parathyroid autotransplantation. An investigation of parathyroid autograft function. 665 65

Parathyroidectomy was carried out in 26 patients over a 14-year period. Excellent results were obtained in patients with severe hyperparathyroidism. Vascular calcification, hypercalcaemia and pruritus did not justify surgery unless associated with unequivocal hyperparathyroidism. 13 patients required intravenous calcium infusion for up to 2 weeks to control post-operative hypocalcaemia. Calcium requirements could be predicted from the pre-operative plasma alkaline phosphatase level. Following operation continued treatment with vitamin D was necessary to prevent hypocalcaemia. Hyperparathyroidism recurred in 1 patient after 8 years and 4 patients developed osteomalacia. Since parathyroid hormone may have toxic effects other than those on bone, maintenance of normal levels should be a long-term objective in the treatment of patients with chronic renal failure. Where large parathyroid glands are present, surgical reduction in gland mass is a logical prelude to long-term suppression of parathyroid hormone with vitamin D and phosphate-binding agents.
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PMID:Parathyroidectomy in chronic renal failure. 668 30

Patients with predialysis chronic renal failure and bone disease were treated with 1 alpha-hydroxy-derivatives of vitamin D. The observation period consisted of 22 patient years. All patients showed histological improvement of renal osteodystrophy after the initial 6 months of treatment. Bone resorption indices improved most strongly. There was also a considerable decrease of non-mineralized osteoid and no change in the total trabecular bone volume. Hypercalcemia occurred 24 times in 9 patients. Although in general the 1,25-(OH)2-vitamin D serum levels were increased at the time of hypercalcemia, as compared to the preceding non-hypercalcemic period, no elevation above the normal range occurred. In cases of hypercalcemia two different groups of patients, with suppressed and non-suppressed levels of iPTH respectively, could be distinguished. In both groups different significant correlations between serum 1,25-(OH)2-vitamin D and serum calcium levels were found. If serum iPTH was not suppressed hypercalcemia was more severe. It is concluded that the occurrence and severity of hypercalcemia in patients with chronic renal failure during treatment with 1 alpha-hydroxy-derivatives of vitamin D is related to the presence of parathyroid hormone.
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PMID:Follow-up of long-term treatment of predialysis renal bone disease with 1-alpha-hydroxy-derivatives of vitamin D. 668 50

The size of the parathyroid gland was evaluated at different functional levels of the gland (control: 216 glands in 54 autopsy cases, chronic renal failure: 74 glands in 21 autopsy cases, hypercalcemia: 16 glands in 15 patients with primary hyperparathyroidism). This study is based on the fact that chronic renal failure causes a hypersecretory state of parathyroid hormone (PTH), and that hypercalcemia suppresses PTH secretion. The size of the parathyroid gland was represented by the largest area cut through the hilum of the gland. Interstitial and fatty tissues were excluded from the measuring. The lower parathyroid glands are larger than the upper glands in the control. Both the upper and the lower glands enlarge with a predominance of the lower glands in size in chronic renal failure. These results suggest that the functional level of the lower glands is higher than that of the upper glands not only in the normal but in a hypersecretory state of PTH. Hypercalcemia has been shown to cause a decrease in size of the lower glands, while the upper glands scarcely decrease in size. This result indicates that the lower glands play a major role in reducing PTH secretion when PTH secretion is suppressed. It is concluded that the lower parathyroid glands play a more important role than the upper glands in the maintenance and regulation of PTH secretion.
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PMID:An evaluation of the size of the parathyroid glands. 674

The state of vitamin D nutrition depends on synthesis in the skin under the influence of sunlight as well as on dietary intake. In European countries that do not fortify milk with vitamin D, reduced sun exposure is the major factor leading to a fall in body stores of vitamin D with age and to a high frequency of hypovitaminosis D in the elderly sick. In the US, because vitamin D is added to milk and the use of vitamin D supplements is more common, the dietary intake of vitamin D is relatively more important than in Europe, and the total vitamin D intake and body stores of vitamin D are generally higher. Nevertheless, body stores of vitamin D probably fall with age in the US as they do in Europe, and it is likely that some sick elderly persons in the US, especially among those confined to institutions, become vitamin D deficient. For several reasons, the vitamin D requirement increases with age, and a total supply of 15 to 20 micrograms/day (600 to 800 IU) from all sources is recommended. Special attention should be paid to persons most likely to need supplementation, such as the housebound, persons with malabsorption, and persons with interruption of the enterohepatic circulation. Osteomalacia, the bone disease produced by severe vitamin D deficiency, is less common in the US than in Europe, but subclinical vitamin D deficiency may contribute to the pathogenesis of hip fractures, both through increased liability to fall and through PTH-mediated bone loss. The extent to which vitamin D deficiency contributes to hip fractures in the US is unknown, and is an important area for future research. Excess intake of vitamin D or of its metabolites may result in hypercalcemia and extra-osseous calcification, particularly in arterial walls and in the kidney, leading to chronic renal failure. The dose of vitamin D that causes significant hypercalcemia is highly variable between individuals but is rarely less than 1000 micrograms/day. Smaller doses can cause hypercalciuria and nephrolithiasis and possibly impaired renal function. Vitamin D administration may raise plasma cholesterol but there is no convincing evidence that the risk of myocardial infarction is increased. The recommended total supply for the elderly of 20 micrograms/day is most unlikely to be harmful, except in patients with sarcoidosis or renal calculi.
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PMID:Vitamin D and bone health in the elderly. 676 68


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