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

Primary hyperparathyroidism (HPT) is a common disorder that mainly afflicts elderly women. It can be diagnosed in at least 1% of all postmenopausal females and autopsy studies indicate an even higher frequency. Although the widespread use of automated serum calcium analyses has increased the awareness of HPT, only 10% of all cases seem to be identified. The diagnosis relies on the demonstration of an inappropriately elevated serum concentration of parathyroid hormone (PTH) relative to the serum calcium value, which need not be markedly raised. Measurements of intact PTH with immunometric methods have considerably improved the diagnostic precision but it is still difficult to evaluate patients with only marginal hypercalcemia. Few patients with diagnosed HPT are completely without symptoms. Symptoms commonly encountered are psychiatric and neuromuscular disturbances. Subclinical bone disease might be relevant but there is insufficient information about its importance in otherwise asymptomatic individuals. Various cardiovascular risk factors appear more commonly in patients with HPT and untreated disease is associated with an increased risk of premature death.
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PMID:Primary hyperparathyroidism: epidemiology, diagnosis and clinical picture. 176 33

The criteria used in selecting patients with asymptomatic hyperparathyroidism (HPT) for surgery remain controversial. Do patients with asymptomatic HPT have less severe disease (smaller glands and less derangement of biochemistry) than those with symptoms? We studied a consecutive series of 111 patients with HPT surgically treated and compared the symptomatic patients (n = 83) and asymptomatic patients (n = 28). There were no significant differences between the two patient groups with respect to age, serum calcium, PTH (intact 1-84), and excised gland weights (adenomas). Hypercalcemia was cured in all patients. The natural history of mild or asymptomatic HPT is unknown, but we summarize the current knowledge relating to mortality, cardiovascular/renal disease, psychiatric and neuromuscular disorders, and bone disease. Symptoms of HPT do not correlate with the degree of biochemical and pathological derangement. Furthermore clinical assessment does not predict severity of disease and should not be the sole basis of selection for surgery. The results of surgery for primary HPT permit us to advocate a liberal approach to the selection of asymptomatic patients for operation.
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PMID:Asymptomatic primary hyperparathyroidism. 176 38

Progression of hyperparathyroidism and bone disease on CAPD has been noted by several authors. In our CAPD patients we observed that aluminium-containing phosphate binders were often required because administration of CaCO3 was limited by the development of hypercalcaemia particularly in patients concomitantly requiring calcitriol. We propose that CAPD fluids with lower calcium concentration should be evaluated to facilitate control of plasma phosphate and secondary hyperparathyroidism.
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PMID:Is control of secondary hyperparathyroidism optimal with the currently used calcium concentration in the CAPD fluid? 132 80

During the study of parathyroid function in 19 hemodialysis patients with low turnover aluminum bone disease, it was observed that serum parathyroid hormone (PTH) levels were higher during the induction of hypocalcemia than during the recovery from hypocalcemia. This type of PTH response has been termed hysteresis. Hypocalcemia was induced during hemodialysis with a calcium-free dialysate. When the total serum calcium level decreased to 7 mg/dL, the dialysate calcium concentration was changed to 3.5 mEq/L and the dialysis session was completed. One week later, hypercalcemia was induced during hemodialysis with a high-calcium dialysate. The mean basal PTH level was 132 +/- 37 pg/mL (normal, 10 to 65 pg/mL; immunoradiometric (IRMA), Nichols Institute, San Juan Capistrano, CA) and increased to a maximal PTH level of 387 +/- 91 pg/mL during hypocalcemia. For the same ionized calcium concentration, the PTH level was higher during the induction of hypocalcemia than during the recovery from hypocalcemia. Conversely, for the same ionized calcium concentration, the PTH level was greater when hypercalcemia was induced from the nadir of hypocalcemia than when hypercalcemia was induced from basal serum calcium. The set point of calcium (defined as the serum calcium concentration required to reduce maximal PTH by 50%) was greater during the induction of hypocalcemia than during the recovery from hypocalcemia (4.44 +/- 0.10 versus 4.25 +/- 0.09 mg/dL; P = 0.03). The mean basal ionized calcium concentration and the mean ionized calcium concentration at the intersection of the two PTH-calcium curves were the same (4.61 +/- 0.13 versus 4.61 +/- 0.12 mg/dL).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hysteresis of the parathyroid hormone response to hypocalcemia in hemodialysis patients with low turnover aluminum bone disease. 177 94

It is generally accepted that some patients affected by mild asymptomatic primary hyperparathyroidism need not be treated with surgery, but may be medically managed without risk. However, our experience regarding 5 of these cases observed in the last two years, suggests a different approach. These patients, initially diagnosed as having mild hyperparathyroidism based on only moderately elevated serum concentrations of calcium and followed medically for years, were referred to us for a sudden worsening of their clinical course. One 35-year-old man presented hemorrhagic gastritis with severe anemia and type II AV block with syncopal attacks. Three women, aged 51, 64 and 65 years, presented with severe hypercalcemia associated with renal failure in two and with marked bone disease in another. In all these cases parathyroid neoplasms were preoperatively localized (by ultrasonography, CT scan and radioactive 201-Tl 99-Tc scan) and surgically removed. Histological examination showed a parathyroid carcinoma in the male patient and single gland enlargements in the three females. A fifth patient, a 65-year-old woman, was referred to us in critical condition: severe hypercalcemia, osteopenia with femur fracture, myocardial infarction and renal failure. She died in a few days, in spite of intensive medical care. These cases suggest that patients with hyperparathyroidism initially diagnosed as "mild" need close medical observation and preferably, in our opinion, should undergo surgery.
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PMID:Acute complications in the course of "mild" hyperparathyroidism. 180 15

Prevention of bone disease associated with impairment of the renal function is desirable. Attempts at such prevention inevitably also embrace prevention of the extraosseous consequences of autonomous hyperparathyroidism, such as the effects of hypercalcaemia, need for parathyroid surgery, and, perhaps, toxic effects of the parathyroid hormone. Strategies for prevention in early, moderate, and end-stage renal failure are reviewed and discussed with particular reference to dietary phosphorus restriction, use of gut phosphorus binders, control of acidosis, calcium supplementation, use of oral and intravenous calcitriol, and use of synthetic analogues of 1,25-dihydroxyvitamin D3. The onset of severe renal osteodystrophy can be delayed. Early attempts at prevention are logical, but we do not know whether these will reduce the need for parathyroid surgery or will make patients feel better or live longer. The costs of prophylaxis--both financial and in terms of incidence and severity of complications--remain to be defined. An individual approach to each patient with renal impairment seems at present appropriate.
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PMID:Prevention of renal osteodystrophy. 181 86

Bone metastases secondary to myeloma, are characterized by severe bone pain, pathological fractures, hypercalcaemia and hypercalciuria. Histological and biochemical investigations have shown a wide spectrum of abnormalities in bone turnover in patients with multiple myeloma. The increased osteoclast activity caused by various osteoclast activating factors secreted by myeloma cells, is responsible for the diffuse localized osteolytic lesions. These lesions are responsible for the symptoms and respond poorly to standard chemotherapy, justifying the use of a bone-sparing agent. Clodronate is a potent inhibitor of osteoclast activity and does not impair bone mineralization. Several studies have shown that clodronate can normalize serum calcium in hypercalcaemic patients with metastatic bone disease, and a similar response is seen in multiple myeloma. In a long-term (18 months) placebo-controlled study we have shown that clodronate, given orally at a daily dose of 1.6g, can decrease both the incidence of pathological fractures and the activity of osteoclasts, as judged by measurements in iliac crest biopsy. These results, along with those from two other studies, are promising and suggest that clodronate may inhibit the progression of osteolytic lesions in multiple myeloma.
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PMID:The use of clodronate in multiple myeloma. 183 98

We compared the presentation features of three series of patients with multiple myeloma diagnosed between 1960 and 1971 (Kyle R, Mayo Clin Proc, 1975, 50, 29, n = 869), 1972 and 1986 (Clinica Medica, University of Pavia, n = 345) and 1987 and 1990 (Cooperative Group for Study and Treatment of Multiple Myeloma, n = 341). In the most recently diagnosed patients, the percentage of those who had symptoms related to multiple myeloma (i.e. any of bone pain, systemic symptoms, disturbances related to hypercalcemia, neurological involvement and hyperviscosity) was reduced (90 vs. 86 vs. 66%) (P less than 0.001), while the percentage of asymptomatic patients diagnosed by chance was increased (not reported, and 14 vs. 34%). In the most recent series, a lower percentage of spontaneous bone pain (68 vs. 60 vs. 37%, P less than 0.001) paralleled a lower incidence of advanced bone disease (osteolyses and pathological fractures, 60 vs. 64 vs. 34%), and renal failure (serum creatinine greater than 1.2 mg/dl) was also less common (56 vs. 44 vs. 33%, P less than 0.01), at least partially due to a decreased incidence of both hypercalcemia (30 vs. 20 vs. 18%, P less than 0.001) and of hyperuricemia (serum uric acid greater than 7 mg/dl, 47 vs. 32 vs. 26%, P less than 0.01). Systemic symptoms (weakness, infections, fever or weight loss) were reported more seldom by recently diagnosed patients, due to a decreased frequency of anaemia (haemoglobin less than 12 g/dl), leukopenia and thrombocytopenia, as well as of the systemic effects of bone pain and of renal insufficiency. These data indicate that multiple myeloma is diagnosed earlier now than in the past, and this must be taken into account when comparing survival data in treated series.
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PMID:Changing clinical presentation of multiple myeloma. 183 56

In patients with either Paget's disease or hypercalcaemia associated with malignancy (HCM) we have assessed the parathyroid response to pamidronate therapy, both by immunoassay of serum intact parathyroid hormone PTH (1-84) and by measurement of indirect parameters of PTH bioactivity, tubular maximum reabsorption of phosphate (TmPO4/GFR) and nephrogenous cyclic AMP (NcAMP). In 12 patients with Paget's disease, therapy with pamidronate produced a small but significant decrease in adjusted serum calcium within the reference interval which was accompanied by a progressive increase in PTH (1-84) secretion and a corresponding fall in TmPO4/GFR and increase in NcAMP. In 12 patients with HCM pretreatment, PTH (1-84) concentrations were suppressed, whilst mean TmPO4/GFR was reduced and NcAMP was increased, compatible in most patients, with parathyroid hormone-related peptide (PTHrP) driven hypercalcaemia. Therapy with pamidronate produced the expected fall in serum calcium but caused an increase in PTH (1-84) secretion in the presence of absolute hypercalcaemia. The initial subnormal TmPO4/GFR decreased further to a nadir on day 5, and there was a corresponding further increase in NcAMP. By day 7, however, when PTH (1-84) concentrations were maximal, there was a significant paradoxical rise in TmPO4/GFR and a corresponding decrease in NcAMP. These data are consistent with a variable trigger point for PTH (1-84) secretion, one consequence of which is a reduction in the risk of hypocalcaemia following pamidronate. The results have major clinical implications for the interpretation of PTH (1-84) measurements in patients who are being treated or about to be treated for bone disease or for hypercalcaemia of malignancy (HCM).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Direct and indirect assessment of the parathyroid hormone response to pamidronate therapy in Paget's disease of bone and hypercalcaemia of malignancy. 184 62

Hereditary hyperphosphatasia is a rare bone disorder characterized by increased bone turnover, elevated alkaline phosphatase (ALP) and bone deformity. We describe a patient with a mild form of hereditary hyperphosphatasia who was initially hypercalcemic in childhood with remission after puberty. Symptomatic hypercalcemia recurred during lactation after each of two pregnancies, associated with increased bone turnover (rise in ALP, osteocalcin, and urine hydroxyproline excretion) which appeared to be independent of changes in major calcium-regulating hormones. The mechanism for the development of post-partum hypercalcemia remains unclear but may relate to the relative estrogen deficiency of lactation. We postulate that acute estrogen withdrawal may result in hypercalcemia in the presence of markedly increased bone turnover.
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PMID:Post-partum hypercalcemia in hereditary hyperphosphatasia (juvenile Paget's disease). 194 65


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