Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0005940 (bone disease)
 7,459 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hyperphosphatemia leads to the development of osteitis fibrosa in patients with chronic renal failure. In contrast, crippling osteomalacia may appear in uremic patients who are hypophosphatemic or aluminum intoxicated or who undergo total or subtotal parathyroidectomy. Thus, strict phosphorus control by use of aluminum-containing gels may ameliorate renal osteitis fibrosa, but may potentiate the development of osteomalacia. To evaluate this possibility, we compared the bone histologies of 10 chronic renal hemodialysis patients who consistently maintained predialysis phosphorus levels between 4-5 mg/dl (Strict-P) to those of 46 randomly selected dialysis patients (Random-P). We found that the Strict-P group had lower circulating immunoreactive PTH (P less than 0.02) and alkaline phosphatase (P less than 0.05) levels and, as expected, less evidence of hyperparathyroid bone disease. On the other hand, the Strict-P patients had osteomalacia, as evidenced by moderate osteoid accumulation and reduced capacity of bone to assume a fluorescent tetracycline label. Furthermore, all Strict-P patients had histological evidence of bone aluminum accumulation. We conclude that maintenance of normal serum P levels with aluminum-containing gels in hemodialysis patients prevents severe hyperparathyroid bone disease. Such treatment, however, is also attended by a moderate degree of aluminum-associated osteomalacia.
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PMID:Does strict phosphorus control precipitate renal osteomalacia? 394 54

Two children with chronic renal failure developed aluminum intoxication as a result of long-term ingestion of aluminum hydroxide for the control of hyperphosphatemia. In each child, bone biopsy confirmed severe osteomalacia, the absence of features of hyperparathyroid bone disease, and massive aluminum deposition at the bone-osteoid junction. Radiographs during the period of aluminum intoxication demonstrated osteopenia, pathologic fractures, fraying of the metaphyses of the long bones, and widening of the physis. When aluminum hydroxide therapy was discontinued (each patient) and aluminum was removed with chelation therapy (one patient), radiographs demonstrated a distinctly unusual pattern of healing. Calcification of the long bones began at the most recently formed osteoid and then proceeded toward the diaphysis. This unusual healing pattern created lucent defects and a transient "bone within a bone" appearance, which resolved with further healing.
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PMID:Aluminum bone disease in children: radiographic features from diagnosis to resolution. 402 26

Three cases of pseudohypoparathyroidism with roentgenographic evidence of hyperparathyroid bone disease are described. Renal resistance to exogenous parathyroid hormone (PTH), the hallmark of pseudohypoparathyroidism, was documented by markedly blunted or absent urinary phosphate and cyclic AMP responses to parathyroid extract. At the time of diagnosis all patients were hypocalcemic and hyperphosphatemic with elevated serum alkaline phosphatase levels and subperiosteal resorption noted on skeletal films. Bone biopsy in one patient revealed a histologic appearance consistent with hyperparathyroidism. Serum PTH levels, measured in two patients while they were hypocalcemic, were elevated. None of the patients had short stature, brachydactyly, subcutaneous calcification or mental deficiency. These cases are compared to the 15 well-documented cases previously reported. The presently available information on pseudohypoparathyroidism indicates a variable skeletal response to PTH mediated by several factors extrinsic to bone and suggests that pseudohypoparathyroidism with hyperparathyroid bone disease is one extreme of a clinical spectrum of skeletal responsiveness to PTH. This disorder is part of an expanding clinical picture which makes pseudohypoparathyroidism a diagnostic consideration in any patient with unexplained hypocalcemia, hyperphosphatemia, elevated alkaline phosphatase levels or metabolic bone disease.
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PMID:Skeletal responsiveness in pseudohypoparathyroidism. A spectrum of clinical disease. 624

The objectives of this study were to evaluate the effects of vitamin D(3) (D(3)) and 1,25-dihydroxyvitamin D(3) (1,25-(OH)(2)D(3)) on uremic bone disease independent of their action on the intestine. The histomorphology of tibial metaphyses in uremic (5/6 nephrectomized [5/6 Nx]) rats fed a low-calcium-low-phosphorus (LCLP) diet was compared with sham-operated (SO) rats fed an LCLP diet and 5/6 Nx rats fed an LCLP diet and given 15,000 IU D(3) or 5 units (135 ng) 1,25-(OH)(2)D(3) daily for 7 days. A marked osteomalacia characterized by an increased percentage of active and inactive trabecular osteoid surface and thickened growth plates developed in proximal tibial metaphyses in 5/6 Nx rats given the placebo, compared with SO rats. These bone changes were associated with relative hypophosphatemia, hypophosphaturia, and hypercalciuria in 5/6 Nx rats. In 5/6 Nx rats treated with D(3) or 1,25-(OH)(2)D(3) the growth plates had undergone mineralization and vascular invasion and were markedly reduced in thickness. Other parameters of osteomalacia in trabecular bone were not different from 5/6 Nx rats given the placebo. There was a significant decrease in osteoclasts per millimeter of trabecular surface perimeter in D(3)- and 1,25-(OH)(2)D(3)-treated rats. These bone changes were associated with hypercalcemia, hyperphosphatemia, and hyperphosphaturia, compared with 5/6 Nx rats given the placebo. It was concluded that in uremic rats fed the LCLP diet, shortterm treatment with either pharmacologic levels of D(3) or 1,25-(OH)(2)D(3) corrected only lesions in the growth plate. Osteoid seams were not reduced in treated rats, although the serum calcium-phosphorus product was elevated. The 5/6 Nx rat fed the LCLP diet appears to be a useful model for the rapid induction of uremic osteomalacia in adult animals.
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PMID:Short-term effects of vitamin D3 and 1,25-dihydroxyvitamin D3 on osteomalacia in uremic rats fed a low calcium-low-phosphorus diet. 626 57

Clinical signs of rickets developed in a previously healthy 13-year-old girl with normal features. She had hypocalcemia, hyperphosphatemia, elevated alkaline phosphatase and parathyroid hormone levels, and normal vitamin D metabolite levels, with osteitis fibrosa cystica on bone biopsy specimen. Her renal function was normal. Treatment with 1 microgram of calcitriol each day resulted in symptomatic and clinical relief and improvement of the serum chemical values. This patient probably has pseudohypoparathyroidism type 1, with renal nonresponsiveness and bone responsiveness. This disorder has the clinical features of rickets, but represents hyperparathyroid bone disease.
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PMID:Renal-nonresponsive, bone-responsive pseudohypoparathyroidism. A case with normal vitamin D metabolite levels and clinical features of rickets. 654 1

Fifteen children undergoing continuous ambulatory peritoneal dialysis for 0.3 to 2.4 years were evaluated longitudinally for renal osteodystrophy. Immunoreactive parathyroid hormone, 25-OHD, total and ionized calcium, inorganic phosphate, and alkaline phosphatase levels were measured regularly. Skeletal radiographic studies were performed at the onset and conclusion of CAPD and at six-month intervals during therapy. All children received 1,25(OH)2D3 and aluminum hydroxide, and nine received supplemental calcium. Plasma 25-OHD concentrations were normal to elevated, and calcium increased steadily to high normal levels despite a trend to persistent hyperphosphatemia. The increased calcium levels suppressed parathyroid hormone overactivity in only one patient. At the onset of CAPD, nine patients had hyperparathyroid bone disease seen radiographically, three of whom also had rachitic lesions. At the end of CAPD, the hyperparathyroid lesions had improved in four patients, completely resolved in three, and deteriorated in two. Rachitic lesions had completely healed in two patients and improved in the third. However, among the six children without radiographically evident lesions at onset of CAPD, hyperparathyroid bone lesions developed in two and rachitic lesions in two others during CAPD. Although CAPD and appropriate therapy benefited most patients with renal osteodystrophy, the benefits were not uniform, and bone lesions deteriorated in some.
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PMID:Renal osteodystrophy in children undergoing continuous ambulatory peritoneal dialysis. 663 99

Pseudohypoparathyroidism (PHP) is a condition characterized by hypocalcemia, hyperphosphatemia, and an impaired phosphaturic response to exogenous parathormone (PTH). A minority of patients with PHP have associated bone disease, and in some the radiological appearances have been suggestive of rickets. We report a patient with PHP who had epiphyseal enlargement and bowing of the long bones similar to that seen in rickets. Radiology showed generalized osteomalacia with failure of epiphyseal calcification and several pseudofractures. Bone biopsy showed increased osteoid seams. The phalanges of both hands showed subperiosteal erosions consistent with hyperparathyroidism. Biochemically, he had persistent hypocalcemia, hyperphosphatemia, and an elevated alkaline phosphatase. Plasma calcitonin, magnesium, and 25-hydroxycholecalciferol levels were normal. The 1,25-dihydroxycholecalciferol level was within the normal adult range but was probably inappropriately low for an adolescent. Plasma parathormone was elevated (1.3--1.7 microgram/liter; normal, < 0.73). His diet was not deficient in vitamin D. Gastrointestinal function was normal. Renal function was normal, apart from an increase in the maximum tubular reabsorption of phosphate (46--52.6 mg/liter glomerular filtration rate; normal, 38 +/- 5). Intravenous PTH infusion tests were performed on the patient and a control subject before and 6 months after serum calcium levels had returned to normal. The maximum increases in cAMP excretion in the patient were 0.03 and 0.05 mmol/g creatinine before and after treatment, respectively (control, 0.53 and 0.24); the maximum increases in phosphate excretion in the patient were 0.14 and 0.04 mmol/g creatinine before and after treatment, respectively (control, 0.32 and 0.07). He responded to initial treatment with a high dose of calciferol and later to 1,25-dihydroxycholecalciferol in a dose of 1 microgram/day. It is considered that renal resistance to PTH is his primary abnormality, with the bone disease representing a secondary phenomenon.
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PMID:Pseudohypoparathyroidism presenting with rickets. 741 91

Following four etiologies are considered as the possible reason for secondary hyperparathyroidism in the previous reports. First, a decreased serum concentration of 1,25(OH)2D3 directly stimulates PTH secretion. Second, hypocalcemia directly stimulates PTH secretion which is independent of 1,25(OH)2D3 action. Third, the presence of decreased calcemic response to PTH. Fourth, there is a strong possibility that hyperphosphatemia indirectly and/or directly may stimulate PTH secretion. The treatment of secondary hyperparathyroidism should be modified according to the stage of uremia. Excess suppression of PTH secretion could cause an adynamic bone disease. Early start of the treatment would be beneficial to prevent the bone from the development of PTH resistance.
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PMID:Pathophysiology and treatment of secondary hyperparathyroidism in patients with chronic renal failure. 749 9

To maximize the effects of calcitriol on parathyroid glands and bone without inducing frequent episodes of hypercalcemia, two new therapeutic approaches, intravenous therapy and intermittent pulse oral administration, have been advocated. To date, detailed results of 23 studies have been reported. All clinical trials were prospective; however, none included a placebo-control group, and only one study reported on bone histology. Review of these data indicates that in principle, both intravenous and pulse oral therapy are equally efficient in decreasing serum parathyroid hormone levels. However, both approaches induce relatively frequent episodes of hypercalcemia and, to a lesser degree, hyperphosphatemia, necessitating close monitoring during therapy. In addition, a subset of patients did not respond to either therapy without clearcut characteristics that would allow them to be identified before the start of therapy. More controlled studies that include bone histology are needed to elucidate this question. At this time, it appears that patients with severe predominant hyperparathyroidism can benefit from intravenous or pulse oral therapy, which may allow them to avoid parathyroidectomy. However, further studies are needed in patients with mild to moderate secondary hyperparathyroidism to determine whether intermittent therapies are superior to daily oral therapy in preventing parathyroid gland hyperplasia and renal bone disease.
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PMID:Calcitriol pulse therapy in patients with end-stage renal failure. 788 85

Adynamic (or aplastic) bone disease is a bone histologic pattern characterized by decreased bone formation rate, low cellularity, and normal or decreased osteoid thickness. It was first described in symptomatic patients undergoing dialysis who were overloaded with aluminum because of contaminated dialysate or chronic ingestion of aluminic phosphate binders; the evidence of the overload was extensive coloration (more than 25%) with aurin tricarboxylic acid, whereas the Perls stain coloration for iron was negative. We have, however, reported these histologic changes in asymptomatic patients with uremia who were never exposed to aluminum, in two patients before end-stage renal failure and in six patients undergoing dialysis. The main step in the prevention of adynamic bone disease is the absolute exclusion of aluminum exposition even by so-called "safe doses" of aluminum phosphate binders because in the long term they are never actually safe. Because idiopathic adynamic bone disease may nevertheless occur, parathyroid hormone suppressive treatment by oral calcium taken with meals as phosphate binders (+/- 1 alpha-hydroxyvitamin D3 derivatives) should be carefully monitored by measurements of plasma concentrations of not only calcium and phosphate but also of intact parathyroid hormone levels. In order to have normal bone formation rate levels, patient intact parathyroid hormone levels should be between one and three times the upper limit of the normal level. Although adynamic bone disease may not be a true bone disease when not due to aluminum, it is a risk factor for increased incidence of hypercalcemia and hyperphosphatemia and therefore for metastatic calcifications. Therefore, when hypercalcemia occurs with hyperphosphatemia and normal intact parathyroid hormone in patients treated with 1 alpha-hydroxyvitamin D3, it is proposed that the latter drug should be discontinued first, whereas oral calcium is increased to correct hyperphosphatemia, and calcium concentration is decreased in the dialysate to prevent hypercalcemia, even though plasma parathyroid hormone may increase up to three times the upper limit of the normal level. In patients previously exposed to aluminum, a deferoxamine test should be performed and a deferoxamine treatment started if the test is positive.
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PMID:Adynamic bone disease in patients with uremia. 807 43


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