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)

Our previous secretin provocation studies in normal volunteers and unoperated duodenal ulcer patients suggested that the gastrin rise in gastrinoma may be an exaggeration of the normal response rather than paradoxical. We report further studies in various clinical settings having normogastrinemia (normal, n = 17; unoperated duodenal ulcer, n = 13; primary hyperparathyroidism, n = 7) and hypergastrinemia (postvagotomy, n = 5; hypochlorhydria, n = 7; achlorhydria, n = 10; chronic renal failure, n = 10; gastrinoma, n = 5). Under all nongastrinoma conditions, there were similar gastrin rises of 9-19% between 2 and 5 min after bolus intravenous GIH secretin (2 CU/kg), which fell to baseline by 8 min, except for chronic renal failure. In chronic renal failure, gastrin remained elevated from 7 to 30 min and was significantly different (p less than 0.05) at 10-30 min compared to all other nongastrinoma conditions except hyperparathyroidism. Peak rises occurred within 5 min in all entities, but only three gastrinoma patients had positive secretin provocation tests by the predefined criterion of a gastrin rise greater than 200 pg/ml. The results of secretin provocation in various clinical entities with and without hypergastrinemia further support the hypothesis that the gastrin rise in gastrinoma is an exaggeration of the normal response. The prolonged gastrin rise seen in chronic renal failure may be due to altered renal clearance, inasmuch as other hypergastrinemic states had responses similar to normal and duodenal ulcer.
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PMID:Secretin provocation: gastrin results in various clinical situations. 334 35

Management of patients with multiple endocrine neoplasia type I (Wermer's syndrome) who have concurrent hypercalcemia and hypergastrinemia is controversial. The usual therapeutic approach has been to perform parathyroidectomy first before surgery for ulcer disease in an effort to decrease serum calcium concentration and presumably remove one of the stimuli for both gastrin and gastric acid secretion. We present the history of a 48-year-old man with primary hyperparathyroidism and Zollinger-Ellison syndrome who underwent acid secretory studies and secretin stimulation tests before and after parathyroidectomy. We also studied the effect of calcium channel blockade on gastrin and gastric acid secretion, since calcium influx into endocrine cells, such as the gastrinoma cell, is thought to be critical in hormone secretion. Although parathyroidectomy reduced serum calcium and parathormone levels to normal, basal serum gastrin concentration and basal acid output remained unchanged. The peak rise in serum gastrin concentration after secretin injection was less after parathyroidectomy than before parathyroidectomy but was still abnormal. During administration of verapamil, a calcium channel antagonist, no change was seen in the serum gastrin concentration, secretin test response, or acid secretion. Basal acid output was 45.4 mmol/hr before parathyroidectomy or verapamil and 54.0 and 50.4 mmol/hr after parathyroidectomy or verapamil, respectively. In contrast, a small but significant decrease (p less than 0.05) in serum parathormone concentration occurred during treatment with verapamil, an observation that to the best of our knowledge has not been previously reported in humans.
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PMID:Lack of effect of parathyroidectomy or calcium channel blockade on serum gastrin concentration and gastric acid secretion in a patient with hyperparathyroidism and Zollinger-Ellison syndrome. 379 19

In vitro studies have demonstrated that secretin can stimulate the release of parathyroid hormone (PTH), but reports concerning its effects on PTH and calcium in vivo are contradictory. To examine this question further, a bolus injection of secretin (75 IU) was given to 12 normal subjects and 10 patients with primary hyperparathyroidism (HPT). Six of the patients had multiple endocrine neoplasia and five had endocrine pancreatic tumours (EPT). Three normocalcaemic patients with EPT were also included in the study. The mean serum gastrin level rose significantly (from 19 to 40 pmol/l, p less than 0.01) within 15 min of secretin injection in the normal subjects. HPT patients without EPT had a somewhat higher mean basal level of gastrin (39 pmol/l, p less than 0.05 compared with controls), but it did not increase significantly after the secretin bolus. In six EPT patients the gastrin concentrations rose by more than 300 pmol/l. Although secretin had a biological capacity to release gastrin, it had no discernible effects on either serum PTH or serum calcium in any of the groups studied. Nor were any changes in PTH or calcium observed when secretin was given as a continuous infusion (3 IU/kg/h) over 90 min. Thus, our data do not support the concept that secretin, in vivo, is a secretagogue of PTH.
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PMID:Effects of secretin on parathyroid hormone and calcium in normal subjects, patients with hyperparathyroidism and patients with gastrinoma. 399 34

The prevalence of hypergastrinemia was determined in 38 consecutive patients with proved primary hyperparathyroidism. Uncorrected serum calcium levels ranged from 2.6 to 4.0 mmol/L and parathyroid hormone levels from 260 to 8750 ng/L (normal less than 600 ng/L). Preoperative serum gastrin levels were grossly elevated (1000 to 4000 ng/L) in three patients (normal median 63 ng/L; range 30 to 120 ng/L). Two patients were achlorhydric. After parathyroidectomy (adenomatous hyperplasia) in the third patient, the serum gastrin level decreased from 4000 to 3000 ng/L, with a negative response to both a secretin challenge and a meal test. The latter patient was subsequently shown to have an adrenal ganglioneuroma and islet cell hyperplasia, neither containing gastrin, and at 4-year follow-up she still has no symptoms from the hypergastrinemia. Eight patients had a modest hypergastrinemia. Serum gastrin levels returned to normal in three of the four patients after parathyroidectomy. The fourth patient had rheumatoid arthritis, which can be associated with hypergastrinemia. The mean plasma gastrin level before operation (100.3 +/- 26.1 ng/L) was similar to the postoperative value (67.0 +/- 18.5 ng/L). There was no correlation between parathyroid hormone and gastrin levels nor between serum calcium and gastrin levels. The three patients with duodenal ulcers did not have elevated gastrin levels. Therefore it would appear that routine screening of patients with primary hyperparathyroidism adds little to their clinical management.
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PMID:Hyperparathyroidism and hypergastrinemia revisited. 650 67

A sensitive radio-immunoassay for parathyroid hormone (PTH) using the commercially available antisera AS 211/32 and AS 211/41 has been established. The lower limit of sensitivity of the assay is 0,25 ng/ml. Seventy-nine per cent of normal subjects have PTH levels in the measurable range, with a mean of 0,49 ng/ml (SD +/- 0,26 ng/ml). Only 1 of 9 patients with proven primary hyperparathyroidism had a normal serum PTH value. The mean serum PTH value in this group was 3,0 +/- 0,26 ng/ml, which differed significantly from that in the normal group (P < 0,001). The serum PTH level of 33 patients on chronic haemodialysis was uniformly raised, while in 8 patients with hypoparathyroidism PTH levels were undetectable. Patients with malignant disease presented a mixed picture, with raised, normal or undetectable PTH levels. We investigated a possible relationship between the gut hormones, gastrin, secretin and cholecystokinin-pancreozymin (CCK-PK) and PTH secretion in human volunteers. No effect was found, although the investigations were conducted over relatively short time periods.
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PMID:Measurement of human serum parathyroid hormone in disorders of calcium metabolism and during administration of certain gut hormones. 740 29

Thrombosis of the left subclavian vein occurred in a 44-year-old man. It was found to be caused by an atypical thymus carcinoid of the anterior mediastinum without carcinoid syndrome. Primary resection was not possible, but it was removed after three cycles of neoadjuvant chemotherapy with doxorubicin, cisplatin, vincristine and cyclophosphamide. Increased concentrations of alkaline phosphatase and parathormone were then noted. Subtotal parathyroidectomy revealed hyperplastic parathyroids. A gastrinoma was suspected from a history of peptic ulcer for many years which had persisted despite a Billroth II gastric resection 10 years ago. Serum gastrin, analysis of gastric secretion and a secretin-stimulating test confirmed the diagnosis. Recurrent episodes of weakness and syncope, in the presence of low blood sugar levels and a positive C-peptide suppression test, were interpreted as due to an insulinoma. There was no evidence of increased hypophyseal or adrenal function. Finally, in the absence of a family history, multiple endocrine neoplasia type 1 (MEN 1) was diagnosed with co-existing primary hyperparathyroidism, gastrinoma, insulinoma and thymus carcinoid. Somatostatin-receptor scintigraphy provided localization of the MEN 1 with enrichment in the thorax and abdomen.
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PMID:[Thymus carcinoid in multiple endocrine neoplasms type I]. 790 23

About 25% of patients with ZES have MEN-1. Except for diarrhoea, less frequent in patients with ZES MEN-1 than in sporadic ZES, and specific MEN-1-related signs, clinical characteristics are similar in both ZES types. Acid output and gastrin level are also similar whether in the basal state or after secretin. Primary hyperparathyroidism (pHPT) exists in the majority of ZES MEN-1 patients, 30% have pituitary adenoma (prolactinomas for half), 30% adrenal involvement, 25-30% have ECLomas: bronchial and thymic carcinoids have probably been underevaluated. Gastrinomas are multiple predominantly located in the duodenal wall, but also in the pancreas in association with clinically silent endocrine tumours. The spread of the disease metastases to the liver (LM), mediastinum, bones, is evaluated best by Octreoscan. Associated endoscopic ultrasonography evaluates the number, size and anatomical characteristics of gastrinomas. Patients without LM have an excellent prognosis. Surgery never cures ZES, but is necessary in cases of associated life-threatening conditions such as insulinoma. Although the size of the tumour, when located in the pancreas >3 cm, favours metachronous LM occurrence, surgery in our experience has not been able to prevent LM development.
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PMID:Diagnostic and therapeutic criteria in patients with Zollinger-Ellison syndrome and multiple endocrine neoplasia type 1. 968 47

Gastrin levels have been reported to be often increased in patients with primary hyperparathyroidism (PHPT) considered to be caused by hypercalcemia. To determine the prevalence of increased basal gastrin and to investigate its causes, 52 consecutive patients with PHPT were studied prospectively, undergoing a clinical, biochemical, and gastric morphofunctional assessment before any parathyroid surgical procedure. This included evaluation of basal and secretin-stimulated gastrin, basal and pentagastrin-stimulated gastric acid secretion, upper gastrointestinal endoscopy, with histological evaluation for gastritis and Helicobacter pylori infection. Twenty of the 52 PHPT patients (38.5%) had increased fasting gastrin. Further investigation allowed us to clearly demonstrate the causes of hypergastrinemia in 16 of these 20 patients. In 7 of 20 (35%), hypergastrinemia was caused by gastric fundus atrophy; in 3 patients (15%), Zollinger-Ellison syndrome with Multiple Endocrine Neoplasia type I was diagnosed; whereas in another 20% of patients, mild hypergastrinemia was ascribed to Helicobacter pylori gastritis. Finally, in 2 patients, additional clinical history revealed an occasional use of the gastric antisecretory drug omeprazole a few days before the serum gastrin determination. This study shows that the hypercalcemic status per se is not sufficient to produce an increase in fasting gastrin levels. Furthermore, gastric fundus atrophy, and not gastrinoma, is the major cause of relevant (>160 pg/mL) hypergastrinemia.
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PMID:Prevalence and causes of hypergastrinemia in primary hyperparathyroidism: a prospective study. 1059 18

About 25% of patients with ZES have MEN 1. Except diarrhoea, less frequent in patients with ZES-MEN 1 than in sporadic ZES, and specific MEN 1-related signs, clinical characteristics are similar in both ZES types. Acid output and gastrin levels are also similar whether in the basal state or after secretin stimulation. Primary hyperparathyroidism (PHPT) exists in the majority of ZES-MEN 1 patients, 30% have pituitary adenoma (prolactinomas for half), 30% adrenal involvement, 25 to 30% have EC-Lomas; bronchial and thymic carcinoids have probably been underevaluated. Gastrinomas are multiple predominantly located in the duodenal wall, but also in the pancreas in association with clinically silent endocrine tumors. The spread of the disease: metastases to the liver (LM), mediastinum, bones, is evaluated at best by Octreoscan. Endoscopic ultrasonography evaluates the number, size and anatomical characteristics of gastrinomas. Patients without LM have an excellent prognosis. Surgery never cures ZES, but is necessary in case of associated life-threatening condition such as insulinoma and has been advocated to prevent LM development in patients with large pancreatic tumor(s). However although, indeed, the size of the tumor, when located in the pancreas > 3 cm, favours metachronous LM occurrence, surgery, in our experience, has not been able to prevent LM development. Hepatic malignancies remain however the most pejorative prognostic determinant for survival and raise the most difficult therapeutic challenge. Surgery is the best option whenever feasible; specific chemotherapy and chemo-embolisation have not conclusively achieved definite successes. Long-term octreotide treatment, however, has been shown recently to obtain tumour stabilisation. Internal irradiation with 90 Ytrium-labelled octreotide is a new promising option, presently under evaluation (Novartis European trial). Preliminary results are promising.
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PMID:[Diagnostic and therapeutic strategies in Zollinger-Ellison syndrome associated with multiple endocrine neoplasia type I (MEN-I): experience of the Zollinger-Ellison Syndrome Research Group: Bichat 1958-1999]. 1514 2

In summary, ZES is a syndrome caused by gastrinoma, usually located within the gastrinoma triangle and associated with symptoms of peptic ulcer disease, GERD, and diarrhea. The diagnosis of ZES is made by measuring fasting levels of serum gastrin, BAO, and the secretin stimulation test. Because of the high association of ZES and MEN1, HPT must be excluded by obtaining a serum calcium and parathyroid hormone level. Treatment of ZES consists of medical control of symptoms with PPIs and evaluation for potentially curative surgical intervention. Noninvasive imaging studies including SRS, CT, and MRI should be performed initially to evaluate for metastases and identify resectable disease. Invasive imaging modalities such as EUS may be performed to further evaluate primary tumors. IOUS, palpation, and duodenotomy are used for intraoperative localization of gastrinomas. In patients with MEN1, surgical resection should be pursued only if there is an identifiable tumor larger than 2 cm and after surgery for the primary hyperparathyroidism (3 1/2-gland parathyroidectomy). All patients with resectable localized sporadic gastrinoma should undergo surgical exploration, even those with biochemical evidence but negative imaging studies. Tumor is most commonly found in the duodenum, and the cure rate is high. In patients with liver metastases, surgery should be considered if all identifiable tumor can be safely removed. A multidisciplinary approach including surgical and nonsurgical therapies should be taken in patients with advanced disease.
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PMID:Current management of the Zollinger-Ellison syndrome. 2429 44


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