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)

We have prospectively investigated calcium and bone metabolism in 16 patients receiving total parenteral nutrition for periods ranging from 7 to 89 months. In 12 patients, bone biopsies at 6 to 73 months after the start of parenteral nutrition showed osteomalacia. Plasma 25-hydroxyvitamin D levels were normal in all patients. Seven persons developed hypercalcemia, and 10 had hypercalciuria with a negative calcium balance. Serum phosphorus was normal and plasma parathyroid hormone level, normal or decreased. Three patients with the severest form of the disease had vitamin D withdrawn from their solutions. Subsequently, urinary calcium decreased, and serum calcium became normal; two persons reverted to a positive calcium balance. Thus, patients receiving total parenteral nutrition may develop metabolic bone disease characterized by osteomalacia, hypercalcemia, hypercalciuria, and a negative calcium balance. This may be caused by both defective mineralization and increased bone resorption induced by vitamin D, its metabolites, or another unrecognized factor.
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PMID:Metabolic bone disease in patients receiving long-term total parenteral nutrition. 676 94

A 13-year-old boy with primary hyperoxaluria and a successful renal allograft developed symptomatic bone disease, hypercalcemia, and hypercalciuria. Transiliac bone biopsy revealed calcium oxalate crystals in the marrow within mononuclear phagocytes and multinucleated giant cells. Deep resorption bays were seen adjacent to these crystal-cell aggregates. Serum 1,25-(OH)2-vitamin D (calcitriol) and iPTH concentrations were low or normal. We suggest that hypercalcemia results from macrophage-mediated bone resorption initiated by Ca oxalate crystal deposition.
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PMID:Calcium-oxalate-crystal-induced bone disease. 704 38

Enzyme replacement therapy for a severely affected 6-month-old girl with hypophosphatasia was attempted by repeated intravenous infusions of alkaline phosphatase-rich plasma, obtained by plasmapheresis, from two men with Paget bone disease. Circulating Paget AP activity was found to have a half-life (two days) similar to that reported in adults, which did not change during a five-week period of six AP infusions. Normalization of the patient's serum AP activity was followed by better control of her hypercalcemia and hypercalciuria. Sequential radiographic studies revealed arrest of worsening rickets with slight remineralization of metaphyses, although urinary excretion of the AP substrates phosphoethanolamine and inorganic pyrophosphate was unaltered by therapy. Our findings suggest that the infantile form of hypophosphatasia results from defective production of AP rather than from accelerated destruction of circulating enzyme, and that hydrolysis of AP substrates like PEA and PPi occurs primarily in tissue rather than blood. Study of additional cases of hypophosphatasia will be necessary to assess the clinical efficacy of this form of enzyme replacement therapy.
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PMID:Infantile hypophosphatasia: enzyme replacement therapy by intravenous infusion of alkaline phosphatase-rich plasma from patients with Paget bone disease. 710 57

Bone involvement in idiopathic calcium nephrolithiasis is characterized by the following abnormalities: a) the bone density is decreased, the severity of bone loss being dependent upon the existence of hypercalciuria and upon the pathophysiology of this latter: it is inconsistent in the absence of hypercalciuria or when hypercalciuria is of the absorptive type I or II, whereas it is almost constant in fasting hypercalciuria without secondary hyperparathyroidism and constant and severe in the rare true renal hypercalciuria. b) The bone histology (which has been evaluated only in idiopathic hypercalciuric patients) mainly shows a defect in bone formation at the exception of the rare renal hypercalciuria. Osteoclastic hyperresorption is only seen in this latter type of hypercalciuria whereas in the other types of hypercalciuria only an increase of the total or inactive resorption surface is observed. This phenomenon is possibly explained only by a delayed refilling of the resorption lacunae secondary to the decreased bone formation. The osteoid thickness is either normal or decreased despite decrease in mineralization apposition rate which seems therefore to be secondary to the decreased bone formation. c) Symptomatic bone disease in hypercalciuric stone formers is exceptional and always related to a severe long term calcium restriction. d) The biochemical markers of bone resorption tend to be increased in idiopathic hypercalciuria. Hydroxyprolinuria is more often elevated than pyridinolinuria. However pyridinolinuria is negatively correlated to bone density. The contrast between the increase of these bone resorption markers and the usual normality of plasma PTH and of the osteoclastic resorptive surfaces, suggest the role of meat induced acid load which may favor inactive resorption by dissolution of bone buffers. A disturbed profile synthesis of cytokines which induce differentiation and proliferation of the osteoclasts and which modulate the osteoblastic proliferation and function (IL-1, IL-6, TNF-alpha, GM-CSF...) may play a role in the bone loss of calcium stone formers but further studies are necessary to precise its transient or permanent involvement in their bone disease. e) The decrease of bone formation may be explained by the suppressed PTH secretion which may be explained by hypercalcitriolemia. This excess of calcitriol synthesis may be secondary either to monocyte increased synthesis of IL-1 which stimulates the renal 1 alpha-hydroxylase by the mean of an increased PGE2 synthesis or to the relative hypophosphatemia of the calcium stone formers comparatively to healthy controls. Hypercalcitriolemia may originate from the activated monocyte itself. The decrease in bone formation may also be secondary to the action of monokines on the osteoblast differentiation and/or function.
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PMID:[Bone involvement in idiopathic calcium lithiasis]. 756 25

We studied three patients with proximal tubulopathy characterized by defective reabsorption of phosphate, glucose, amino acids, urate, and low molecular weight proteins. This tubulopathy differs from Fanconi syndrome in that the patients had normal plasma bicarbonate and absorptive hypercalciuria associated with increased 1,25-dihydroxyvitamin D levels. The youngest patient was rachitic and may be classified with previously described patients, whereas the other two patients presented with nonrachitic osteopenic bone disease and their tubulopathy started during adult life. Kidney defects appeared sequentially in one of the nonrachitic patients. The two brothers of the youngest patient had similar kidney and bone disturbances. One of the other two patients had a brother with similar kidney reabsorption defects; an additional brother was probably affected and a sister presented with glycosuria, but no other reabsorption defects. The findings in these two families suggest a genetic transmission of proximal tubulopathy. The third case was sporadic. Renal histology of the three patients showed a great number of giant cells in the tubular lumen. We conclude that, at least in our adult patients, tubulopathy may represent a new entity among the proximal tubular dysfunction cases described to date. The features of this proximal defect suggest that it may be caused by a selective alteration of luminal cell membrane transport of phosphate, glucose, amino acids, urate, and proteins in the presence of a normal sodium gradient across the tubular cell membrane.
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PMID:Nonacidotic kidney proximal tubulopathy with absorptive hypercalciuria. 784 48

Phosphate plays a central role in many of the basic processes essential to the cell and organism. In particular, skeletal mineralisation is dependent on the appropriate regulation of phosphate in the body, and any disturbances in phosphate homeostasis can have severe repercussions on the integrity of bone. The kidney regulates the serum levels of phosphate by tubular mechanisms which are not fully understood. Furthermore, the processes involved in regulating renal tubular phosphate reabsorption are complex, and involve a large number of factors. It is not surprising therefore that defects in renal phosphate handling result in a failure of bone mineralisation. There are three well characterised conditions which are associated with renal tubulopathies resulting in a phosphate leak, with consequent bone disease. Two are familial, hypophosphataemic rickets (HYP), and hereditary hypophosphataemic rickets with hypercalciuria (HHRH). The third is acquired via a tumour, oncogenic hypophosphataemic osteomalacia (OHO), and may well have relevance to the inherited hypophosphataemias. Recent advances in molecular genetics are permitting the identification of genes involved in human diseases from their chromosomal location. These approaches are now being applied to the analysis of the hypophosphataemias. The isolation of the genes responsible for the renal tubulopathies will be an important achievement. Ultimately this will help to increase our understanding of the mechanisms involved in the control of phosphate handling in the body.
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PMID:Molecular biology of hypophosphataemic rickets and oncogenic osteomalacia. 795 77

Idiopathic osteoporosis is a syndrome appearing in adult men and women, and is different from idiopathic juvenile osteoporosis which appears in the growth period. It is characterised histomorphometrically by decreased values in bone volume, trabecular thickness, active osteoid surface, mineralization surface and bone formation rate. Hypercalciuria, which appears in many cases, is thought to reflect this depressed metabolic state of the bone. Diagnosis depends on the exclusion of all the primary endocrine disturbances and metabolic bone disease. The presence of subclinical metabolic abnormality should be carefully searched out.
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PMID:[Idiopathic osteoporosis]. 796 87

A patient who had been supported with total parenteral nutrition (TPN) for over 8 years is herein presented, with emphasis on the changes observed in calcium metabolism. The patient was a 31-year-old female, who had undergone a subtotal jejunal and ileal resection for superior mesenteric artery occlusion. TPN was started soon after the surgery. She had been on TPN support for 105 months. Back pain developed at 97 months after the initiation of TPN. During her course, the serum calcium levels were judged to be within the normal ranges, while the 1 alpha, 25(OH)2Vit.D declined. Intermittent hypercalciuria was occasionally observed. Both the serum level of calcium and urinary calcium loss correlated closely to the amount of calcium infused, but they were not influenced by the amount of vitamin D (ergocalciferol) received. The serum level of parathormone and calcitonin were also within the normal ranges. The patient's vertebral bone, which was obtained at autopsy, revealed histopathological changes characteristic of osteoporosis. Based on the above, we conclude that a careful monitoring of the amount of calcium infused is called for to prevent bone disease in patients on long-term parenteral nutrition.
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PMID:Long-term total parenteral nutrition and osteoporosis: report of a case. 829 58

The effects of endocrine disease on bone mass continue to attract attention. Investigations include the effects on the skeleton of thyroid disease, primary hyperparathyroidism, and their treatment. The effect of growth hormone replacement in adults with panhypopituitarism has also been investigated; children with treated growth hormone deficiency appear to reach adulthood with low bone mass. The indications for surgery in asymptomatic primary hyperparathyroidism have recently been reviewed. The associations between autoimmune thyroid disease and connective tissue disease have been investigated. Although patients with Graves' disease are frequently positive for antinuclear antibodies, there appears to be no increased risk of systemic autoimmune disease. The possible pathogenesis of diabetic bone disease via calcium malabsorption, hypercalciuria, reduced bone formation, and collagen abnormalities has been reviewed. A long-term study has clarified the links among diabetic control, limited joint mobility, nephropathy, and retinopathy. The possible mechanisms by which pregnancy may induce remission in rheumatoid arthritis have been discussed.
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PMID:Endocrine disease. 843 94

Burn patients are at risk for bone disease due to aluminum (Al) exposure from use of antacids and albumin, partial immobilization, and increased production of endogenous glucocorticoids. Moreover, severely burned children are growth impaired up to 3 years after the burn. To determine the extent of bone disease, we studied nine men and three women, ages 18-41 years, with greater than 50% body surface area burn. Seven patients underwent iliac crest bone biopsy following double tetracycline labeling, one additional patient expired after a single label, and three others had postmortem specimens obtained for quantitative Al only. Serial serum and urine samples were obtained weekly until biopsy or death. All biopsied patients had reduced bone formation and osteoid area, surface, and width, with mineral apposition rate, osteoblast surface, and osteoclast number with normal eroded surfaces compared to age- and sex-matched normal ambulatory volunteers. Burn patients also had reduced bone formation, mineral apposition rate, osteoid area, and surface compared to age-matched volunteers at short-term bed rest. Serum levels of osteocalcin were low. Most patients had mild hypercalcemia but only a third had hypercalciuria. All patients had elevated Al in blood or urine; urine Al correlated inversely with serum osteocalcin. In 60% significant bone Al was detectable by stain or quantitation. Our data are compatible with burn patients having markedly reduced bone turnover. Al loading, partial immobilization, endogenous corticosteroids, and cytokine production may be among the etiologic factors.
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PMID:Bone disease in burn patients. 845 88


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