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)

Changes in the excretion of urinary cyclic AMP, calcium and phosphate, and serum calcium, ionized calcium, and magnesium were studied after parathyroidectomy for primary hyperparathyroidism. Urinary cyclic AMP decreased rapidly and 8 of 11 patients had a significant reduction 1 h postoperatively, but changes in serum calcium and ionized calcium were delayed. Serum calcium concentrations closely parallelled those of serum ionized calcium and phosphate excretion returned to normal almost 7 h later than that of cyclic AMP. Excretion of urinary calcium rose rapidly at 4 h after surgery because calcium clearance improved after the reduction in circulating parathyroid hormone. The fall in urinary calcium at about 24 h was due to the subsequent reduction in serum calcium.
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PMID:Changes in cyclic AMP and electrolytes after parathyroidectomy in primary hyperparathyroidism. 630 50

Twenty-seven hypercalcaemic subjects were identified in three generations of a family. There were no clinical complications of chronic hypercalcaemia, but five had had parathyroid surgery which was unsuccessful in four. Twenty of the twenty-seven subjects were compared with twenty-four normocalcaemic controls from the same family and the findings were also compared with those from forty patients with surgically proven primary hyperparathyroidism. The relation between the serum and urinary calcium levels was studied by means of an oral calcium loading test. The ratio of calcium clearance to creatinine clearance was normal in this family (but elevated in the patients with primary hyperparathyroidism) and the concentration of parathyroid hormone was normal, as was the total urinary excretion of cyclic AMP. Thus, there was no evidence of either suppressed or increased parathyroid activity in this familial condition. Basal urinary calcium excretion was normal under steady-state conditions indicating that the hypercalcaemia could not be attributed to either increased bone resorption or increased calcium absorption from the gut. In accordance with this, the serum levels of 1,25-dihydroxycholecalciferol were normal. The hypercalcaemia in this condition can be accounted for in full by an increase in renal tubular reabsorption of calcium, and thus differs from that of primary hyperparathyroidism in which there is increased production of calcium from gut and/or bone as well as an increase in renal tubular reabsorption of calcium. Although the serum phosphate and renal tubular reabsorption of phosphate were both low in patients with familial benign hypercalcaemia, they were not as low as in patients with the same degree of hypercalcaemia due to primary hyperparathyroidism. The changes in phosphate transport in familial benign hypercalcaemia could be explained as a secondary effect of the increased filtered load of calcium in the kidney. The tendency towards hypermagnesaemia in our patients, which contrasts with a tendency towards hypomagnesaemia in primary hyperparathyroidism, could also be explained as a secondary effect of the abnormality of renal tubular reabsorption of calcium. Increased renal tubular calcium reabsorption and persistent normal functioning of the parathyroid glands in the face of hypercalcaemia remain the sole definite abnormalities of the syndrome.
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PMID:Familial benign hypercalcaemia. Study of a large family. 631 Jun 72

Clinical and biochemical evidence of primary hyperparathyroidism (prim. HPT) is reported in an infant with hypotonia, feeding problems and constipation from birth. Following a partial parathyroidectomy at the age of 12 months, the clinical condition improved. In her sister, mother and three other maternal relatives a familial hypocalciuric hypercalcemia (FHH) was subsequently demonstrated. All were clinically healthy in spite of increased total and ionized serum calcium, normal serum parathyroid hormone concentration, low urinary calcium excretion and normal renal excretion of cyclic AMP. Similar findings appeared in our patient after parathyroidectomy. An autosomal dominant inheritance of FHH is suggested. It is thus demonstrated, that a mother with FHH may give birth to healthy children with FHH as well as to infants with prim. HPT associated with FHH.
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PMID:Primary hyperparathyroidism in infancy associated with familial hypocalciuric hypercalcemia. 631 30

Serum vitamin D metabolites, the renal tubular maximum reabsorptive rate for phosphate (TMP/GFR) nephrogenic cyclic AMP (NcAMPI, and CaE (urinary calcium excretion per litre of glomerular filtrate) were measured in 14 adults with familial hypocalciuric hypercalcaemia (FHH). The findings were compared with analyses in 14 patients with surgically proven primary hyperparathyroidism matched for serum calcium, creatinine clearance and vitamin D status (assessed by serum concentrations of 25 hydroxyvitamin D). Vitamin D metabolites were also measured in 16 normocalcaemic relatives of patients with FHH. The serum concentration of 24,25 dihydroxycholecalciferol was appropriate for the prevailing 25 hydroxyvitamin D and no difference was found between groups. The serum concentration of 1,25 dihydroxycholecalciferol was significantly greater in primary hyperparathyroidism (P less than 0.0005) compared with patients with FHH and their normocalcaemic relatives. TMP/GFR was reduced in both primary hyperparathyroidism (0.53 +/- 0.12 mmol/l GF, mean +/- SEM) and FHH (0.86 +/- 0.14 mmol/l GF). Patients with primary hyperparathyroidism showed an increase in NcAMP output in the urine (38.5 +/- 16 mmol/l GF) which was significantly greater (P less than 0.0001) than the normal NcAMP (13.5 +/- 9.2 nmol/l GF) found in FHH. CaE was low in FHH indicating increased renal tubular reabsorption of calcium. It is concluded that there is no abnormality of vitamin D metabolism in FHH comparable with the changes observed in primary hyperparathyroidism. It is suggested that the biochemical abnormalities in FHH cannot be explained solely upon an increased sensitivity of the renal tubules to the effects of endogenous parathyroid hormone.
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PMID:Familial hypocalciuric hypercalcaemia: observations on vitamin D metabolism and parathyroid function. 631 24

Studies were performed in 60 patients with proven primary hyperparathyroidism pre-operatively and in 54 of these patients post-operatively, 22 patients with permanent hypoparathyroidism and 34 normal subjects. Urinary and nephrogenous cyclic AMP excretion were increased in the hyperparathyroid patients with an overlap of values with the normal group of 10 and 9%, respectively. Values fell in all patients post-operatively, and were decreased in those with permanent hypoparathyroidism. TmPO4 /GFR was decreased in the preoperative hyperparathyroid patients and rose postoperatively while it was increased in the hypoparathyroid patients with an overlap of values with the normal group of 9%. Post-operative hypocalcaemia due to bone hunger was associated with continuing normo- or hypophosphataemia and urinary cyclic AMP that exceeded 4.5 nM/dl GF while those who developed permanent hypoparathyroidism had hyperphosphataemia, increased TmPO4 /GFR and urinary cyclic AMP that was less than 3.5 nM/dl GF. Urinary and nephrogenous cyclic AMP were equally effective in characterizing patients with primary hyperparathyroidism and less effective in distinguishing patients with hypoparathyroidism from normal while TmPO4 /GFR estimates were more effective in delineating the hypoparathyroid state.
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PMID:Urinary and nephrogenous cyclic AMP and renal phosphate handling in normal subjects and patients with parathyroid dysfunction. 632 23

The mechanism accounting for normal calcemia in certain cases of primary hyperparathyroidism (HPT) remains unclear and more generally the relative importance of each determinant of calcemia has not been systematically studied so far. 52 primary HPT patients with stable calcemias, ranging from 95 to 137 mg/l, were investigated. They all exhibited identical ionized to total plasma calcium ratios. Values of serum iPTH and nephrogenous cyclic AMP were similarly elevated in all patients, and all displayed similar high values for net bone resorption and intestinal absorption of calcium. Tubular reabsorption of calcium was normal or slightly subnormal in the normocalcemic subgroup, and rose in proportion to the increase in serum calcium in the hypercalcemic subgroup. No correlation was found between tubular reabsorption of calcium on the one hand and serum immunoreactive calcitonin, degree of phosphate depletion, sodium urinary excretion or magnesemia on the other. Plasma acid base equilibrium was normal in all patients. Finally, after surgical removal of adenomas, fasting calciuria and intestinal absorption of calcium returned to normal. It is concluded that (1) the main determinant of plasma calcium value in stable calcemia primary HPT is tubular reabsorption of calcium and (2) the absence of correlation between the tubular reabsorption of calcium and the degree of PTH hypersecretion suggests that as yet undetermined factors interfere with the tubular action of PTH.
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PMID:Normocalcemic primary hyperparathyroidism: resistance to PTH effect on tubular reabsorption of calcium. 649 58

Two cases of familial hypocalciuric hypercalcemia (FHH) are reported with a review of the literature. Both cases had hypercalcemia, hypophosphatemia, variable parathormone (PTH) levels and hypocalciuria. The parathyroid glands were only slightly hyperplastic and subtotal parathyroidectomy did not reduce the hypercalcemia. FHH is an autosomal dominant congenital disease with high penetrance. It is characterised by hypocalcemia. This contradictory biological finding should alert the physician to the diagnosis and initiate a familial enquiry. The serum PTH and urinary cyclical-AMP levels do not distinguish FHH from primary hyperparathyroidism. Surgery is usually contraindicated because it is ineffective and because the disease is usually benign. Semi-quantitative bone histology in a patient with a high PTH level was normal. The value of bone biopsy in these cases is discussed.
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PMID:[Familial hypocalciuric hypercalcemia: two case reports (author's transl)]. 711 60

Outpatient renal stone formers belonging to the established urolithiasis subgroups and controls were examined with respect to urinary and serum citrate (Cit) and several associated variables. Only in the normocalciuric majority of calcium and in uric acid stone formers was Cit in 24-hour urine decreased, but was normal in 2-hour fasting morning, and in 3-hour postprandial urine following a Cit-free test meal. Serum Cit was elevated in normocalciuria, renal and resorptive hypercalciuria. This Cit constellation was associated with either normal (absorptive, renal hypercalciuria) or low (normocalciuria, uric acid stone formers) parathyroid gland function as assessed by serum parathyroid hormone and nephrogenous urinary cyclic AMP, except in patients with primary hyperparathyroidism. In 2-hour morning urine the magnesium/creatinine ratio (normocalciuria) and ammonia excretion (uric acid stone formers) were decreased, while ammonia in 24-hour urine was low in all stone formers. It is suggested that Cit metabolism is altered in renal stone disease in general, and that in normocalciuria, stone inhibitors (Cit; magnesium) may be deficient.
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PMID:Citrate in urine and serum and associated variables in subgroups of urolithiasis. Results from an outpatient stone clinic. 712 65

Between July 89 and June 92, 70 patients with primary hyperparathyroidism underwent adenomectomy by unilateral incision under local anesthesia (Ul/LA), without exploration of the remaining glands. The procedure was carried out with intraoperative monitoring of urinary cyclic AMP (n = 35), Calcemia was measured 6-monthly for one year in every patient. 62 (88.6%) patients were cured after Ul/LA, whereas 5 patients required conversion to bilateral cervicotomy under general anesthesia because of abnormal hormonal levels, thus giving an overall success rate of 97% (67/70). The reasons for treatment failure of Ul/LA included misleading conclusions of cervical ultrasonography (n = 5), agitation of the patient (n = 1) and deep localization of the adenoma (n = 1). When cervical ultrasonography is suggestive of a parathyroid adenoma in expert hands, the probability of a second localization or associated hyperplasia is very low, so that adenomectomy by Ul/LA can be attempted safely, provided that the serum level of intact parathyroid hormone returns to normal values within one hour following resection. In our experience, parathyroidectomy by Ul/LA should not be considered in case of non conclusive ultrasonography, familial history pf hyperparathyroidism of MEN-I, ultrasonic evidence of several enlarged glands or associated thyroid nodule requiring simultaneous treatment.
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PMID:[Surgery of primary hyperparathyroidism by unilateral approach under local anesthesia and intraoperative determination of PTH 1-84]. 785 82

Lithium has proved to be a highly effective preventive measure in mood disorders and an increasing number of patients are receiving long-term lithium carbonate therapy. Among other biologically and clinically important effects of lithium, the possible induction of hyperparathyroidism was first suggested in 1973 by Garfinkel et al. About thirty other case reports have since been described, but they could simply have represented the coincidental occurrence of primary hyperparathyroidism and lithium carbonate treatment in the same patients. Eleven cross-sectional studies of calcium metabolism in patients treated with lithium carbonate have been reported. Evidence of a causal relationship of lithium to hyperparathyroidism can lead to a loss of effectiveness of lithium in controlling the affective symptoms. Interestingly, coexistence with hypothyroidism is not uncommon. Low serum phosphate, high serum chloride are also observed. Bone mineral content may decrease. In addition, several studies have shown that lithium treatment increases serum magnesium level. Unusual metabolic features are associated with hyperparathyroidism and long-term lithium treatment: low urinary calcium excretion, absence of nephrolithiasis, and normal urinary cyclic AMP excretion. Lithium inhibition of PTH sensitive adenylcyclase in the kidney would explain these features. In vitro studies suggested that lithium is a potent inhibitor of several hormone responsive adenylcyclase systems. It is possible that the tissue susceptibility to adenylcyclase inhibition in an individual may decide the nature of endocrine dysfunction seen during lithium treatment. Information about the time course with which abnormalities may develop is derived from longitudinal studies. Several months to several years are needed for lithium inducing primary hyperparathyroidism. In vitro studies provide strong evidence that lithium can induce a shift in the set-point for inhibition of PTH secretion by calcium and a direct stimulation of PTH secretion. The extent to which we can extrapolate these data to the clinical situation is discussed. In vivo data from Shen an Seely are compatible with these two mechanisms. These alterations should cause parathyroid hyperplasia. The possibility that a generalized parathyroid stimulus might lead to formation of a single adenima is not proved. Several recommendations regarding parathyroid function in patients receiving lithium have been suggested. Measurement of total calcium and serum proteins or of serum calcium ion values when available should be performed before therapy is begun. If elevated values are obtained, lithium treatment should be deferred and evaluation for hyperparathyroidism performed. Serum calcium should be monitored periodically during lithium treatment. Sustained hypercalcemia or true hyperparathyroidism require parathyroidectomy. If hypercalcemia is mild without complication and psychiatric symptoms well controlled, perhaps surgery should not be employed.
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PMID:[Hyperparathyroidism with lithium]. 808 38


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