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)

Tumour cells produce systemic or local factors which can stimulate osteoclast development and activity leading to increased bone resorption. The clinical consequences are bone pain, fractures and hypercalcaemia. Inhibitors of osteoclast-mediated bone resorption, such as the bisphosphonates, are now the treatment of choice for tumour-induced hypercalcaemia. Recent evidence indicates that these compounds, especially the newer ones, reduce skeletal morbidity in patients with metastatic bone disease and improve their quality of life. Better understanding of the mechanisms underlying tumour-induced bone resorption and development of more potent and less toxic bisphosphonates will lead to improved management of patients with malignant diseases involving the skeleton.
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PMID:Modulation of tumour-induced bone resorption by bisphosphonates. 152 54

Parathyroid activity, bone aluminum (Al) metabolism, bone histology, and clinical bone disease were studied in 55 successfully grafted kidney recipients at transplantation (Tx) and after 1 yr of immunosuppression with a low dose corticosteroid and a high dose cyclosporin-A regimen. Symptoms of Al-related bone disease disappeared after Tx. Serum Al and stainable bone Al decreased. The rate of Al removal from the bone surfaces was independent of graft function (creatinine range, 62-415 mumol/L) and bone turnover. Osteoblast activity and bone formation rate increased, while mineralization lag time normalized. Indices of bone resorption remained elevated, indicating persisting hyperparathyroidism. Eighteen percent of the recipients had posttransplant hypercalcemia, most likely caused by incomplete involution of hyperplastic parathyroid glands, while 53% had normocalcemic hyperparathyroidism related to impaired graft function. Cortical thickness decreased, while cancellous bone volume remained stable after Tx; both indices correlated significantly at follow-up with their respective values at Tx. None of 46 radiologically examined recipients had aseptic bone necrosis 1 yr after Tx.
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PMID:Aluminum metabolism and bone histology after kidney transplantation: a one-year follow-up study. 156 61

Breast and prostate carcinomas are the tumors most commonly associated with skeletal metastases, and the skeleton is the most common site of metastatic disease and of first distant relapse in breast cancer. Bone metastases are the source of considerable morbidity, including pain and functional disability, fractures, hypercalcemia, and epidural compression. The classical radionuclide bone scan remains the most effective tool for the screening of metastatic bone disease, but X-rays are more specific and remain the essential tool for the diagnosis and characterization of bone metastases. Computed tomography is much more useful to diagnose early metastatic involvement of bone, particularly of the spine. Patients with exclusive skeletal metastatic involvement are still frequently excluded from classical therapeutic trials because of the difficulties in the assessment of response. Recalcification of osteolytic lesions is indeed required when defining an objective response, but this criterion is insensitive and not quantitative. Moreover, the development of new osteoblastic lesions is often of difficult interpretation. A concomitant bone scan will help, but the absence of quantification of the changes and the "flare" phenomenon limit the usefulness of the technique. Pain and quality of life constitute simple, but frequently neglected, parameters of response to therapy. The clinical utility of tumor markers and of biochemical markers of bone turnover should also be more fully investigated. Neoplastic osteolysis is essentially mediated by the osteoclasts, which seem to be activated, maybe indirectly through the osteoblasts, by some tumor products. Various substances of tumoral origin have been proposed as mediators for this osteoclast activation, such as transforming growth factors, prostaglandins, and, more recently, products of the immune cells or parathyroid hormone-related peptide.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Metastatic bone disease: clinical and therapeutic aspects. 158 Nov 21

Bone and joint pathology in patients undergoing long-term dialysis for end-stage renal failure is presented in the light of typical cases and a brief review of the literature. Osteomalacia with bone pain and fractures is caused mainly by aluminium overload due to enteral uptake from aluminium-containing phosphate binders. This is why calcium acetate or calcium carbonate should be used exclusively to lower enteral phosphate reabsorption. If--due to hypercalcemia--aluminium containing phosphate binders--cannot be entirely avoided, they should never be administered together with citrate (citrate-containing medication, fruit juice, etc.), which chelates aluminium and thereby massively increases enteral aluminium uptake. Secondary hyperparathyroidism with overt radiologically demonstrable bone disease develops in many patients on long-term dialysis despite efforts to maintain plasma calcium within or slightly above the upper normal range and concomitant treatment with calcitriol. Intravenous administration of relatively high-dose calcitriol or 1-alpha-OH-D3 (neither readily available at the present time), as well as the newly developed experimental vitamin D analogs such as 22-oxa-(OH)2-D3, which appear to suppress the parathyroid glands without increasing enteral calcium reabsorption, may in future reduce the high incidence of parathyroidectomy in patients on maintenance dialysis. beta 2-microglobulin amyloidosis is a new disease entity which develops in the majority of long-term dialysis patients. Apart from carpal tunnel syndrome, trigger fingers and tendon ruptures, it is associated with acute and chronic painful erosive arthropathy with joint effusions and fractures, particularly around the hip, due to cystic bone lesions where bone is replaced by nodular amyloid deposits.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Bone and joint problems in long-term dialysis]. 159 6

At start of dialysis most patients have histological bone abnormalities. These can be divided into two groups--high turnover and low turnover bone disease. Low turnover aplastic disease was previously attributed to aluminum accumulation but is now known to occur even in patients with less than 5% surface stainable aluminium. It is characterised by a mineralisation defect, thin osteoid seams, decreased numbers of osteoclasts and osteoblasts and absent aluminium staining. We have avoided aluminium containing phosphate binders (ACPBs) completely, with a combination of oral calcium carbonate and "low calcium" (1.25 mMol/l) dialysis fluid. Phosphate control has been good (mean less than 1.6 mMol/l) and over the first twelve months serum PTH levels have fallen significantly. Transient asymptomatic episodes of hypercalcaemia have occurred but no patient required ACPBs. Bone biopsies at the start of CAPD in 34 patients showed over 50% to have osteitis fibrosa (OF) but in five cases (15.6%) the aplastic lesion was found without aluminium staining. In seven follow-up biopsies OF improved in 3 cases, osteomalacia improved in 1, became aplastic in 1, while aplastic bone worsened in 1 and changed to mild OF in 1. We conclude that the predominant bone lesion in our patients at start of CAPD is OF, but 15% already have aplastic bone. "Low calcium" dialysis fluid enables ACPBs to be avoided in the majority of CAPD patients.
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PMID:Renal osteodystrophy in CAPD. 168 Apr 34

Progressive bone disease in multiple myeloma frequently leads to osteolysis, bone resorption, pathologic fractures, vertebral compression, and hypercalcemia. We conducted a double-blind study in 173 newly diagnosed multiple myeloma patients of etidronate disodium (EHDP), a diphosphonate compound that reduces bone resorption by inhibiting osteoclastic activity. The patients were randomly assigned to receive oral EHDP 5 mg/kg/d or placebo until death or discontinuation due to intolerance or refusal. The extent of vertebral deformity was measured by a vertebral index as well as height. The frequency of pathologic fractures, hypercalcemia, and bone pain was regularly assessed, as well as size and number of osteolytic lesions. All patients received melphalan and prednisone daily for 4 days every 4 weeks as the primary chemotherapy for their disease. Although the repeated measures analysis showed a significant height loss, there was no difference between treatment arms (P = .98). There was no significant difference in bone pain, episodes of hypercalcemia, or development of pathologic fractures. Patients on EHDP showed less deterioration in their vertebral index, but this difference only approached statistical significance (P = .07). We conclude that EHDP therapy used in this dosage schedule does not have a clinically significant impact in multiple myeloma.
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PMID:Effect of daily etidronate on the osteolysis of multiple myeloma. 171 35

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.
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PMID:Bisphosphonates. Pharmacology and use in the treatment of tumour-induced hypercalcaemic and metastatic bone disease. 172 40

Renal transplantation is associated with several abnormalities of function and structure of the musculoskeletal system. Some of these skeletal problems result from incomplete resolution of abnormalities of bone and mineral metabolism present at the time of transplantation. In this regard, persistent hyperparathyroidism, diabetes mellitus type 1, and accumulation of beta 2-microglobulin may lead to residual skeletal effects despite excellent function of the allograft. Persistent hyperparathyroidism may accelerate bone loss and increase the risk for osteonecrosis, as well as cause hypercalcemia and hypophosphatemia; some patients with severe hyperparathyroidism require parathyroid surgery. Osteonecrosis is the most debilitating skeletal complication after transplantation and frequently requires surgical therapy. Although osteomalacia associated with aluminum overload generally resolves after transplantation, bone complications due to dialysis amyloidosis and diabetes mellitus type 1 often fail to improve. Alternatively, skeletal abnormalities can be acquired after transplantation. Most of the new derangements of bone and mineral metabolism are due to the immunosuppressive medications. Toxic effects of glucocorticoids on bone contribute to the pathogenesis of osteonecrosis, increase the risk for fractures by decreasing cancellous bone mass and synthesis of bone matrix, and dampen the linear growth response in pediatric recipients. Whether cyclosporine independently causes appreciable toxic effects on bone metabolism is not yet clear, but use of this drug increases the prevalence of gout and dental problems. Osteonecrosis, osteopenia, and short stature remain important skeletal complications in recipients of renal allografts. Therapeutic efforts should be directed toward alleviating pretransplant bone disease and attenuating bone loss after transplantation.
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PMID:Musculoskeletal complications after renal transplantation: pathogenesis and treatment. 129 May 51

Primary hyperparathyroidism was thought 30 years ago to be a rare disease, and the diagnosis was most often made in patients presenting with either bone disease or kidney stones. Today the minority of patients with hyperparathyroidism present with such symptoms, a fact accounted for by the introduction into general medical practice three decades ago of laboratory technology for efficiently determining the serum concentrations of various blood minerals, including calcium. Hypercalcemia was detected more frequently, and it was realized that most patients with hyperparathyroidism either had minor symptoms, such as constipation, polyuria, tiredness, and muscle weakness, or they were "asymptomatic" and indistinguishable from normal subjects. It was thought that primary hyperparathyroidism was a progressive disease and that sooner or later all patients would become symptomatic and require parathyroidectomy. Since this operation was curative in a high percentage of cases, it was recommended for virtually all patients once the diagnosis was established. In this contribution the long-term benefits of parathyroidectomy in patients with and without symptoms from primary hyperparathyroidism are reviewed. It is concluded that a multicenter prospective randomized trial is needed to resolve the indications for operative and nonoperative management of patients with this disease.
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PMID:Surgical therapy of patients with primary hyperparathyroidism: long-term benefits. 176 66

Over the last 25 years, the perceived clinical spectrum of primary hyperparathyroidism (HPT) has changed dramatically from a disorder characterized by severe bone and renal disease to one typically manifested by few or mild symptoms and little evidence of organ damage. Reasons for this change in spectrum include changing demographics (primary HPT is primarily a disease of the middle-aged and elderly), diffusion of medical knowledge leading to a higher index of suspicion, and improved clinical laboratory technology (especially inexpensive and accurate determination of serum calcium and parathyroid hormone). In the first 343 cases of primary HPT seen at the Massachusetts General Hospital, 57% had renal stones, 23% had hyperparathyroid bone disease, and less than 1% had no symptoms. By contrast, studies dating from the availability of automated serum calcium measurement found renal stones and hyperparathyroid bone disease in less than 5% of cases, and about half of cases had few or no symptoms. Most patients with primary HPT today have mild, nonspecific symptoms, such as weakness, fatigue, and mental depression, and such signs as arterial hypertension and osteopenia, and detection of their hypercalcemia is generally serendipitous. The mildness and slow progression seen in many cases of primary HPT has resulted in much controversy about appropriate management.
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PMID:Clinical spectrum of primary hyperparathyroidism: evolution with changes in medical practice and technology. 176 71


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