Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0221002 (primary hyperparathyroidism)
 4,921 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hypercalcaemia is often associated with malignant disease. Causes of elevated serum-calcium levels in the absence of bony metastases include parathyroid-hormone production by the tumour, osteolytic factors made by the tumour, and coexistent primary hyperparathyroidism. By measuring nephrogenous cyclic-A.M.P. excretion to assess parathyroid-hormone function, we have determined the mechanism of such hypercalcaemia in 15 patients. Nephrogenous cyclic A.M.P. ranges from 0.05 to 2.40 mumol/g of creatinine in normal subjects, from 2.27 to 8.45 mumol/g in patients with primary hyperparathyroidism, and from 0.50 to 1.30 mumol/g in patients with proven non-hyperparathyroid hypercalcaemia without malignancy. 9 patients (60%) with hypercalcaemia and malignancy had normal levels of nephrogenous cyclic A.M.P. (range 0.35-2.07 mumol/g creatinine). The other 6 (40%) had elevated nephrogenous cyclic A.M.P. (range 2.70-5.55 mumol/g) consistent with increased parathyroid-hormone secretion. Surgical exploration of the neck in these patients showed that the increased parathyroid-hormone secretion was secondary to primary hyperparathyroidism, not ectopic hyperparathyroidism. Thus, the data indicate that coexistent hyperparathyroidism may be common in patients with hypercalcaemia and malignancy and that the measurement of nephrogenous cyclic A.M.P. is very useful in identifying patients at risk for hyperparathyroidism.
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PMID:Primary hyperparathyroidism in paraneoplastic hypercalcaemia. 7 31

A patient with metastatic islet cell carcinoma of the pancreas, recurrent peptic ulcer disease, and hypergastrinemia (Zollinger-Ellison syndrome) developed symptomatic hypercalcemia and renal insufficiency; she was treated with streptozotocin after parathyroidectomy failed to control her hypercalcemia. Shortly after somewhat less than the usual recommended dose of streptozotocin was administered, the serum calcium concentration fell to near normal with complete resolution of symptoms. Seven months after therapy, mild hypocalcemia, consistent with her degree of renal impairment was noted. However, mild hypercalcemia recurred 13 months after therapy. Shortly after streptozotocin therapy, the mean serum gastrin concentration fell to near normal with radiographic disappearance of the anastomotic ulcer. At 7 and 13 months after therapy, serum gastrin levels were normal. Streptozotocin therapy was accomplished without major complications; specifically, without a detrimental effect on the creatinine clearance. Thus, although hypercalcemia in patients with pancreatic islet cell tumors is often due to associated primary hyperparathyroidism, in some patients it may be due to secretion of a hypercalcemic substance from the tumor and may respond to streptozotocin. Similarly, hypergastrinemia in patients with islet cell tumors may also respond to streptozotocin.
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PMID:Pancreatic islet cell carcinoma with hypercalcemia and hypergastrinemia: response to streptozotocin. 13 70

A test was developed to diagnose various forms of hypercalciuria. A two-hour urine sample after an overnight fast and a four-hour urine sample after 1 g of calcium by mouth were tested for calcium, cyclic AMP and creatinine. The 24 patients with absorptive hypercalciuria had normocalcemia and normal fasting urinary calcium (less than 0.11 mg per milligram of urinary creatnine). Urinary calcium was high (greater than or equal to 0.2 mg per milligram of creatinine) after a calcium load. Of the 28 patients with primary hyperparathyroidism (resorptive hypercalciuria), 25 had hypercalcemia and 21 had high fasting urinary calcium. Urinary cyclic AMP, elevated in 30 per cent of fasting patients, was high (greater than 4.60 mu moles per gram of creatinine) in 82 per cent of cases after calcium load. Six patients with renal hypercalciuria had normocalcemia, high fasting urinary calcium, and high (greater than 6.86 mu moles per gram of creatinine) or high-normal fasting urinary cyclic AMP was normal. This simple test should facilitate the differentiation of various causes of hypercalciuria.
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PMID:A simple test for the diagnosis of absorptive, resorptive and renal hypercalciurias. 16 60

Effects of parathyroidectomy on parathyroid function and calcium (Ca) metabolism were carefully evaluated in 6 patients with primary hyperparathyroidism without symptoms normally attributed to the disease and in 7 with bone disease or nephrolithiasis. Before parathyroidectomy, both groups of patients demonstrated evidence of the sequelae of parathyroid hormone (PTH) excess, since they presented one or more of the following features: low bone density by 125I-photon absorption, hypercalciuria (urinary Ca greater than 200 mg/day on an intake of 400 mg/day), negative Ca balance (absorbed Ca less than urinary Ca), elevated fasting urinary Ca greater than 0.2 mg/mg creatinine for a night-time sample after a 6-hour fast), and decreased renal function (creatinine clearance of less than 65 ml/min). Following parathyroidectomy, most of these deleterious effects were reversed commensurate with the return of immunoreactive serum PTH, serum Ca, and urinary cyclic AMP toward normal. These quantitative non-invasive techniques may be useful for the initial evaluation and follow-up of patients with asymptomatic primary hyperparathyroidism.
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PMID:Metabolic effects of parathyroidectomy in asymptomatic primary hyperparathyroidism. 17 69

The clinical utility of urinary cyclic adenosine-3',5'-monophosphate (cAMP) determinations has been limited by the overlap between hyperparathyroid and normal patients. We evaluated the potential of the parathyroid hormone (PTH)-dependent, nephrogenous cAMP in the diagnosis of hyperparathyroidism. Twenty-three patients with primary hyperparathyroidism and 19 control subjects had two-hour urine collections and blood sampling at midpoint. Nephrogenous cAMP level was calculated as total urinary cAMP excretion minus the amount filtered. The total urinary cAMP excretion (micromols per gram of creatinine) was higher in hyperparathyroid patients (6.8 +/- .5 SE), but overlapped with values obtained in controls (2.9 +/- .15). The level of nephrogenous cAMP (percent of total) was also higher in hyperparathyroid patients (72.5 +/- 1.8) than controls (26.3 +/- 4.1) and clearly separated the groups. Determination of nephrogenous cAMP levels may be useful in the diagnosis of hyperparathyroidism.
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PMID:Nephrogenous cyclic AMP levels in primary hyperparathyroidism. 18 49

Urinary cyclic AMP (UcAMP) appropriate for the serum calcium concentration was determined in normal subjects during the base-line state and during alteration in their serum calcium concentrations by saline and calcium infusions. This was compared to the UcAMP in 76 patients with hypercalcemia and 5 patients with hypocalcemia. In 54 of 56 patients with primary hyperparathyroidism, the UcAMP was inappropriately high for their serum calcium concentration, the 2 exceptions having renal failure. In four patients with vitamin D intoxication, sarcoidosis, milkalkali syndrome, and thiazide-induced hypercalcemia and in five patients with hypocalcemia due to hypoparathyroidism, the UcAMP was appropriately low for their serum calcium concentration. In 16 patients with nonparathyroid neoplasms, 10 had UcAMP levels that were inappropriately high suggesting ectopic parathyroid hormone (PTH)-mediated hypercalcemia and 6 had UcAMP levels that were appropriately low suggesting that their hypercalcemia was due to osteolytic factors other than PTH. Correlations between UcAMP, serum calcium concentration, and carboxyl-terminal immunoreactive PTH suggest that random UcAMP is a sensitive accurate reflection of circulating biologically active PTH. If there is adequate renal function (serum creatinine concentration less than 2.0 mg/dl), a random UcAMP expressed as mumol/g creatinine and analyzed as a function of the serum calcium concentration completely separates patients with PTH and non-PTH-mediated hypercalcemia.
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PMID:Urinary cyclic AMP analyzed as a function of the serum calcium and parathyroid hormone in the idfferential diagnosis of hypercalcemia. 18 21

Plasma hCT levels were less than 50 pg/ml in 50 normal subjects. In 16 patients with medullary carcinoma of the thyroid (MCT), plasma hCT levels were distinctively elevated and they fell significantly after total thyroidectomy, but in 11 of them plasma levels were still high, indicating the presence of metastases. In 74 patients with the other types of malignancy, plasma hCT levels were found to be high in 9 cases (3 oat cell carcinoma of the lung, 4 malignant carcinoids, one malignant pheochromocytoma and one acute myelocytic leukemia). Except for the leukemic case, all these tumors were derived from neural crest. In 12 patients with primary hyperparathyroidism, plasma hCT levels were less than 20 pg/ml. In 13 hypoparathyroid patients, two with pseudohypoparathyroidism and one with pseudoidiopathic hypoparathyroidism, plasma hCT levels were slightly elevated. Some patients with uremia had elevated plasma hCT levels, but there was no relation between plasma levels of hCT and those of PTH, urea nitrogen or creatinine. In response to Ca (4.5 mg/kg/10 min) or tetragastrin (4 mug/kg/5 min) infusion, a marked increase in plasma hCT was observed in all patients with MCT, but not in normal subjects. In 5 hypoparathyroid patients, a significant increase to both stimuli was also observed in all cases. Two patients with pseudopseudohypoparathyroidism responded to the Ca load. These results indicate that the determination of plasma hCT levels especially after a short Ca or tetragastrin infusion is important to study various pathological conditions.
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PMID:Plasma human calcitonin (hCT) levels in normal and pathologic conditions, and their responses to short calcium or tetragastrin infusion. 19 Dec 50

Urinary cyclic AMP excretion per 24 h or per g creatinine in primary hyperparathyroidism (1 degrees HPT) has been evaluated by several authors with conflicting results. In 50 patients with 1 degrees HPT, 25 patients with secondary (2 degrees) HPT and 35 healthy control persons we determined urinary cyclic AMP per 24 h or per g creatinine. These parameters did not satisfactorily discriminate patients from controls, especially when glomerular filtration rate (GFR) as determined by creatinine clearance was reduced. Since urinary cyclic AMP is derived from plasma by glomerular filtration and from kidney by tubular production-the amount of tubules is reflected by GFR-the cyclic nucleotide was related to GFR. In controls urinary cyclic AMP correlated better with GFR than with creatinine excretion. Additionally, in 45 of 50 patients with 1 degrees HPT and in all with 2 degrees HPT, urinary cyclic AMP/GFR was raised. In 1 degrees HPT serum levels of parathyroid hormone correlated closer with urinary cyclic AMP/GFR than with urinary cyclic AMP/g creatinine. The ratio cyclic AMP/GFR decreased to normal or subnormal values after removal of adenomatous or hyperplastic glands in 1 degrees HPT and during infusion of calcium in 2 degrees HPT. In 50 patients with renal lithiasis caused by diseases other than 1 degrees HPT (anatomical variations, pyelonephritis, immobilization after tetraplegia) the ratio cyclic AMP/GFR was not raised. Urinary cyclic AMP/GFR, therefore, reflects parathyroid hormone excess more reliably than cyclic AMP/g creatinine.
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PMID:Hyperparathyoidism: influence of glomerular filtration rate on urinary excretion of cyclic AMP. 19 82

Nephrogenous cyclic AMP (NcAMP), total cyclic AMP excretion (UcAMP), and plasma immunoreactive parathyroid hormone (iPTH), determined with a multivalent antiserum, were prospectively measured in 55 control subjects, 57 patients with primary hyperparathyroidism (1 degrees HPT), and 10 patients with chronic hypoparathyroidism. In the group with 1 degrees HPT, NcAMP was elevated in 52 patients (91%), and similar elevations were noted in subgroups of 26 patients with mild (serum calcium </=10.7 mg/dl) or intermittent hypercalcemia, 19 patients with mild renal insufficiency (mean glomerular filtration rate, 64 ml/min), and 10 patients with moderate renal insufficiency (mean glomerular filtration rate, 43 ml/min). Plasma iPTH was increased in 41 patients (73%). The development of a parametric expression for UcAMP was found to be critically important in the clinical interpretation of results for total cAMP excretion. Because of renal impairment in a large number of patients, the absolute excretion rate of cAMP correlated poorly with the hyperparathyroid state. Expressed as a function of creatinine excretion, UcAMP was elevated in 81% of patients with 1 degrees HPT, but the nonparametric nature of the expression led to a number of interpretive difficulties. The expression of cAMP excretion as a function of glomerular filtration rate was developed on the basis of the unique features of cAMP clearance in man, and this expression, which provided elevated values in 51 (89%) of the patients with 1 degrees HPT, avoided entirely the inadequacies of alternative expressions. Results for NcAMP and UcAMP in nonazotemic and azotemic patients with hypoparathyroidism confirmed the validity of the measurements and the expressions employed.
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PMID:Nephrogenous cyclic adenosine monophosphate as a parathyroid function test. 19 23

The diuresis of cAMP in primary hyperparathyroidism was significantly higher at 7.3 +/- 2.5 mumol/g creatinine X 24 h (P less than 0.005) than that in healthy subjects (3.5 +/- 0.7 mumol/g creatinine X 24 h). After successful operation on the parathyroid gland, cAMP diuresis usually decreased within 24 hours to normal or subnormal values. In primary or secondary hypoparathyroidism subnormal amounts of cAMP (P less than 0.005) were excreted. The method gives false-negative results in functional disorders of the parathyroid glands accompanied or caused by renal failure.
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PMID:[The diuresis of cyclic adenosine-3'5'-monophosphate (cAMP) in primary and secondary disorders of the parathyroid glands]. 20 Apr 7


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