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Query: UMLS:C0020437 (hypercalcemia)
 10,293 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To investigate whether conventional criteria suffice to differentiate between hyperparathyroid and aluminum (Al)-related bone disease, we obtained bone biopsies from 7 patients with chronic renal failure (CRF) at the time of PTX and 3.5-36 months later. All had hypercalcemia and elevated mid-region parathyroid hormone levels and 3 had bone pain at PTX. Bone histomorphometry revealed that 5 patients had hyperparathyroid bone disease at PTX, while 2 had osteomalacia and skeletal Al deposits. Retrospective determination of intact PTH showed normal levels at PTX in the latter two. PTX effectively reduced all indices of parathyroid hyperactivity, but the two patients with Al-related bone lesions did not improve clinically nor histologically after PTX. Intact PTH and/or bone biopsy prior to PTX could have deterred surgery in those with Al-related bone disease.
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PMID:Chronic renal failure: diagnostic measures before parathyroidectomy. 781 73

A total of 295 patients with lytic bone metastases from breast cancer were randomized to receive chemotherapy or chemotherapy plus pamidronate (Aredia) 45 mg intravenously every 3 weeks. Primary endpoints were time to progressive bone disease (evaluated by blind extramural review), and improvement in pain (according to a 6-point self-assessment scale). Secondary endpoints included incidence of bone-related complications (pathological fractures, tumor-induced hypercalcemia, need for radiotherapy), sclerotic response of lytic lesions, WHO performance status, and analgesic score. Median time to bone progression was 249 days and 168 days in the pamidronate and control groups respectively (p = 0.02). Marked improvement in bone pain was observed in 44% of patients receiving pamidronate compared to 30% in controls (p = 0.025). With respect to secondary endpoints, pamidronate reduced the need for radiotherapy (66 times vs. 82 times in controls), and median time to radiotherapy was 697 days with pamidronate, 571 in the control arm. No severe adverse reactions or worsening of chemotherapy-induced toxicities were observed during 1598 pamidronate infusions. We conclude that intravenous pamidronate is well tolerated, significantly prolongs time to progressive bone disease, and significantly improves bone pain in patients with osteolytic metastases from breast cancer.
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PMID:Delayed progression of bone metastases with pamidronate therapy in breast cancer patients: a randomized, multicenter phase III trial. 787 61

In 1954, when I gave a talk on calcium homeostasis at the first Gordon Conference on Bones and Teeth, it was recognized that the level of ionic calcium in the plasma and body fluids must be maintained with precision, since it is critically important for a number of vital processes. However, very little was known of the mechanisms involved and I decided to make this the focus of my research career. With the assistance of a number of first-year medical students working during the summer, we developed a precise method for measuring calcium, demonstrated the remarkable constancy of plasma calcium in normal human subjects, and found that normal calcium levels were restored quickly after being artificially raised or lowered. We focussed on parathyroid hormone (PTH), which plays a key role in controlling hypocalcemia by stimulating osteolysis. While studying the control of its secretion in 1961, we discovered a second calcium-regulating hormone (calcitonin) which was released by hypercalcemia and lowered plasma calcium by inhibiting osteolysis. It is a straight-chain peptide with 32 amino acids and a 7-membered disulfide ring at the N terminal. It is produced by C cells which arise from the neural crest and is considered a neuropeptide hormone. It is produced in the thyroid of mammals and the ultimobranchial glands of lower vertebrates. We were involved in the isolation of salmon calcitonin, which is the form most widely used in therapy because of its high potency. In addition to inhibiting bone resorption, it is a powerful analgesic agent with a potency in certain circumstances which is 30-50 times that of morphine. It is widely used clinically for the treatment of Paget's disease, hypercalcemia, osteoporosis, and relief of bone pain. World sales in 1992 exceeded US$900 million, of which 85% was for osteoporosis.
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PMID:Calcitonin: discovery, development, and clinical application. 792 3

X-linked hypophosphatemia, currently one of the most prevalent varieties of familiar rickets, is attributed to renal phosphate wasting secondary to a gene defect localized to X p22 chromosomal region. The proximal tubular phosphate reabsorption defect is associated with blunted 1,25-dihydroxyvitamin D synthesis to hypophosphatemia or parathyroid hormone administration. It is characterized clinically by hypophosphatemia, growth retardation, and rickets especially in male patients. As the affected patients mature, pseudofractures, skeletal deformities, osteomalacic bone pain, progressive ankylosis, and dental caries occur, which may be alleviated and even prevented with adequate medical therapy. Long term treatment combines phosphate supplementation with calcitriol, augmented occasionally by diuretics. Hypercalcemia, hyperparathyroidism, and nephrocalcinosis are potential complications which require careful monitoring and continued investigations. The use of recombinant human growth hormone to augment renal tubular reabsorption of phosphate and to promote linear growth remains to be examined in well controlled, clinical trials.
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PMID:X-linked hypophosphatemia: molecular biology and treatment controversies. 804

This is a retrospective, clinical study evaluating the long-term outcome of subtotal parathyroidectomy (PTX) in 60 patients with chronic renal failure and severe secondary hyperparathyroidism. Patients were 41 +/- 2 years old (mean +/- SE) at the time of PTX, and followed for 69 +/- 6 months since the procedure. At the time of PTX, three patients had chronic renal failure, 53 had been on chronic hemodialysis, and four had received successful kidney transplants. In more than 80 per cent of patients, symptoms of hyperparathyroidism (bone pain and muscle weakness) resolved within weeks, and biochemical signs (hypercalcemia, and high plasma alkaline phosphatase and parathyroid hormone concentrations) returned to normal ranges within a year. Subperiosteal resorption, bone fractures, and soft tissue calcification frequently improved. Osteosclerosis (rugger-jersey spine), cystic bone changes, osteopenia, and vascular calcifications were, however, often unchanged or progressive. Five patients (8%) who had either persistent or recurrent hyperparathyroidism required additional surgical procedures, and two had subsequent improvement. Twelve patients who had aluminum associated bone disease diagnosed later continued to progress with a high incidence of bone fractures and severe osteopenia. Cystic bone changes, especially of the carpal bones, in association with carpal tunnel syndrome, probably representing amyloid bone disease, also did not respond to PTX. In conclusion, PTX is an effective surgical procedure to reverse complications of hyperparathyroidism in patients with end-stage renal disease, provided that other causes of osteodystrophy, such as aluminum or amyloid-associated bone diseases, are adequately excluded. We feel that subtotal PTX, leaving a small remnant in place, is the procedure of choice.
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PMID:Long term results of subtotal parathyroidectomy in patients with end-stage renal disease. 806 33

Tumor-induced hypercalcemia (TIH) and tumor-induced osteolysis (TIO) are essentially due to a marked increase in osteoclast-mediated bone resorption. Parathyroid-hormone-like protein plays an essential role in TIH, and maybe in TIO, but other substances, such as growth factors or cytokines, could contribute to the osteoclast activation and osteoblast inhibition secondary to the neoplastic infiltration of the skeleton. Treatment of TIH essentially consists of volume repletion and administration of potent anti-osteolytic drugs. Intravenous administration of the bisphosphonate clodronate or pamidronate is particularly useful for this. Pamidronate at a dose of 1.0-1.5 mg/kg as a single 4- to 24-h infusion can normalize serum calcium in about 90% of hypercalcemic cancer patients. The apparently low response rate of bone metastases to systemic antineoplastic therapy seems essentially to reflect the relative insensitivity of our current methods for assessing response in TIO. Quantitative evaluation of pain and of newly developed biochemical markers of bone turnover could be particularly useful for early assessment of response. Prolonged administration of oral pamidronate could reduce by almost one-half the complications of TIO, and iterative bisphosphonate infusions could induce a dramatic relief of bone pain in one-third and a sclerosis of lytic lesions in one-fourth of the cases. These data must, however, be confirmed in randomized blind trials and many questions remain unanswered concerning the optimal therapeutic schemes. Despite these limitations, medical therapy of TIO by non-cytotoxic means has already become a reality.
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PMID:Medical treatment of tumor-induced hypercalcemia and tumor-induced osteolysis: challenges for future research. 814 98

The renal involvement in patients with multiple myeloma has been described as a sign of poor prognosis. The influence of renal insufficiency in the clinical patterns and in the prognosis of patients with multiple myeloma was studied retrospectively in 45 patients. Patients with renal insufficiency, at first visit, more often presented weight loss, proteinuria, hypercalcemia. The means of uricemia, ESR, were higher and the hematocritic mean was lower in patients with renal insufficiency. There was no difference in edema, arterial hypertension, fractures and bone pain. The reversibility of renal insufficiency occurred in 47% of the cases, which happened more often in the first months of the follow up. The creatinine mean was lower in patients with reversible renal insufficiency. The median survival was: patients with renal insufficiency: 11 months; patients with normal renal function: 50 months. Among patients with renal insufficiency those with recuperation of renal function showed a higher median survival (24 months) than those with irreversible renal insufficiency (1 month). The renal involvement then is frequent and often reversible. Patients with impaired renal function showed a worse prognosis; normalization of the renal function was associated with a better outcome.
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PMID:[Clinical characteristics and prognostic implications of renal involvement in multiple myeloma]. 822 May 5

The diagnosis of primary hyperparathyroidism most often results from the incidental finding of hypercalcemia. In two recent cases of osteitis fibrosa cystica (OFC), however, patients without adequate access to health care served as graphic reminders that the clinical spectrum of the disease includes bone disease, and that OFC can be the presenting manifestation of long-standing primary hyperparathyroidism. Both patients complained of bone pain and had widespread osteolytic bone lesions in addition to hypercalcemia on a multitest biochemical panel. The presumptive diagnosis of malignancy with bone involvement (metastatic cancer or multiple myeloma) led to random bone marrow trephine biopsies. Examination of the bone marrow biopsy material revealed the characteristic pathology of OFC, leading to appropriate diagnosis and surgical management of large parathyroid adenomas in both patients.
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PMID:Osteitis fibrosa cystica simulating metastatic tumor. An almost-forgotten relationship. 824 19

The principal pathophysiologic alteration in severe hypercalcemia accompanying hyperparathyroidism and malignancy is enhanced osteoclastic bone resorption. Hypercalcemia impairs renal mechanisms that lead to sodium and calcium excretion; PTH and PTHrP acting on renal tubules enhance further calcium reabsorption. Although rehydration is often necessary as an initial therapy of hypercalcemia, the cornerstone of therapy is to inhibit osteoclastic bone resorption. The bisphosphonates, plicamycin, gallium, and calcitonin all inhibit osteoclastic bone resorption. Calcitonin is the most rapidly acting agent. Toxicities of calcitonin are minimal, yet its therapeutic efficacy is limited by lack of potency and tachyphylaxis. The second-generation bisphosphonates such as pamidronate represent a class of compounds that are extremely effective in inhibiting the metabolic function of the osteoclast. Given in a single infusion, a significant majority of patients will have normalization of corrected serum calcium lasting, on average, 1-2 weeks. Therapeutic benefit will be of greater duration because most patients remain only minimally symptomatic until corrected serum calcium rises above 11.5 mg/dL. Side effects of low-grade fever, hypophosphatemia, hypomagnesemia, and hypocalcemia may occur. Gallium nitrate is a potent inhibitor of bone resorption and may be of increased clinical value when more efficient administration protocols can be developed. Plicamycin, available for two decades, has cumulative toxicities and is less potent than the aminobisphosphonates. Renal insufficiency often accompanies severe hypercalcemia. The nephrotoxicity of gallium nitrate and plicamycin should preclude their use when there is moderate impairment of renal function, and amino bisphosphonates become the treatment of choice in these patients. Although several authors have advocated individualized approaches to the management of hypercalcemia, the potency and duration of action of the aminobisphosphonates make them a reasonable treatment choice for most patients with symptomatic hypercalcemia. Most importantly, the most effective therapy for hypercalcemia is to recognize and treat the underlying disease. Acute primary hyperparathyroidism requires surgery. The effective treatment of hypercalcemia of malignancy allows the introduction of tumor-specific therapy, limits morbidity, and shortens and deintensifies hospitalization. At times, the most appropriate and compassionate decision (particularly in patients with malignancy who have exhausted all therapeutic options and have relentless bone pain) is to withhold therapy for hypercalcemia. Future therapies directed at the osteoclast, such as more potent later-generation bisphosphonates; inhibitors of osteoclast attachments and inhibitors of peptides, which stimulate osteoclastic bone resorption, may permit safe, easily administered, outpatient therapies that will improve the quality of life for hypercalcemic patients.
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PMID:Pathophysiology and management of severe hypercalcemia. 832 91

Plasma cell myelomas in horses have been reported infrequently. Data from 10 cases, 9 from the literature and 1 new case, are used to characterize the disease in the horse. Hot-blooded horses (7/10), specifically Quarter Horses (4/10), were most often affected. Median age at diagnosis was 11 years (range, 3 mo-22 yr) and both male (5) and female horses (5) were represented equally. Clinical findings included weight loss (6/8), anorexia (4/8), fever (4/8), limb edema (4/8), pneumonia (3/8), rear leg paresis/ataxia (3/8), epistaxis (3/8), palpable lymphadenopathy (2/8), and bone pain (2/8). Anemia (8/8) was present routinely, and in three horses, RBCs were macrocytic. Leukopenia (2/8), thrombocytopenia (2/8), and circulating plasma cells (3/8) were variable findings. Except for abnormal protein concentrations and hyponatremia (3), abnormal results from serum biochemical analysis including hypocholesterolemia (1), hypercalcemia (1), and azotemia (1) were reported infrequently. Hyperproteinemia (8/9), hypoalbuminemia (7/9), and hyperglobulinemia (8/9) were characteristic but not invariable findings. Monoclonal proteins (7/7) were detected in the alpha 2, beta, or gamma region by serum electrophoresis. The paraprotein's heavy chain, determined in four horses, was a subclass of IgG. Three horses had decreased concentrations of normal immunoglobulins. Variable proteinuria (trace to 4+) was detected by routine urinalysis in four of six horses. Bence Jones proteinuria was detected in one of five horses (heat precipitation) and monoclonal proteins were detected in two of three electrophoresed urine samples. Three of the horses had lytic bone lesions detected radiographically. Bone marrow aspirates were diagnostic in two of five horses.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Plasma cell myeloma in the horse. A case report and literature review. 833 11


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