PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Pituitary Function Tests”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources
PubMedDate not supplied

Pituitary atrophy in Korean (epidemic) hemorrhagic fever: CT correlation with pituitary function and visual field.

Eleven patients with Korean (epidemic) hemorrhagic fever were each studied three times with high-resolution CT in order to demonstrate necrosis of the pituitary gland and to correlate the CT findings with the patients' pituitary function and visual fields. Seven of the 11 patients showed varying degrees of progressive decrease in the height of the pituitary gland: one severe, two moderate, and four mild. The visual fields of all the patients were checked at the time of the third (last) follow-up CT. Six of the 11 patients had bitemporal superior quadrantanopsia. In five patients, the decreased height (atrophic change) of the pituitary gland and the visual-field defect were coincidental. The visual-field defects in those patients were not improved on follow-up examination 5 weeks later. Two patients in whom a 1-year follow-up examination was performed showed no interval changes in the defects. Pituitary function tests were performed in nine of the 11 patients (six with atrophic pituitary glands and three without atrophic changes) at the time of the third CT. Five of the six patients with atrophy showed decreased pituitary reserve function for follicle-stimulating hormone, cortisol, or human growth hormone, while only one patient showed decreased reserve function for cortisol among the three patients without atrophic change. The pituitary atrophic changes observed on follow-up sellar CT are thought to be the result of the ischemic necrosis of the gland. The high probability (five of seven) of visual-field defects in those patients with atrophic glands suggests optochiasmatic and pituitary ischemia as the basic pathogenesis.

Adult↗
PubMed1992

Pituitary function before, during, and after chronic gonadotropin-releasing hormone agonist therapy.

OBJECTIVE: To examine possible adverse effects on pituitary function of long-term administration of gonadotropin-releasing hormone agonist (GnRH-a). DESIGN: Prospective analysis of blood sampling before, during, and after GnRH-a therapy. SETTING: Tertiary institutional outpatient care. PATIENTS: Twelve normally ovulatory women with a diagnosis of endometriosis. INTERVENTIONS: Six-month suppression with GnRH-a. MAIN OUTCOME MEASURES: Serum levels of follicle-stimulating hormone, luteinizing hormone, free thyroxin index, cortisol (F), growth hormone (GH), prolactin (PRL), and thyroid-stimulating hormone (TSH). RESULTS: Basal and stimulated values of gonadotropins, PRL, F, TSH, and GH were normal and unchanged by 6 months of GnRH-a after resumption of menses. CONCLUSIONS: Utilizing dynamic pituitary function tests, we were unable to demonstrate an adverse effect of long-term GnRH-a therapy on pituitary function.

Adult↗
PubMed2006

Combining growth hormone releasing hormone-arginine and synacthen testing diminishes the cortisol response.

OBJECTIVES: The GHRH/arginine test and short synacthen test (SST) have been validated as safe alternatives to the insulin tolerance test for the assessment of the GH reserve and hypothalamic-pituitary-adrenal axis integrity, respectively. However, these two tests are usually performed separately. The objective was to see whether the synacthen and GHRH/arginine tests could be combined to save time and blood samples and minimize inconvenience to patients. PATIENTS/METHODS: Twenty-four consecutive patients with adult onset pituitary disease requiring pituitary function testing were randomized to receive sequentially and in random order a SST, a GHRH/arginine test, and a combined SST and GHRH/arginine test on three different visits separated by at least 1 wk. RESULTS: There was no difference in basal cortisol or ACTH values for the SST done alone or during the combined test. However, when GHRH/arginine was given with synacthen, patients had a lower peak cortisol response with a mean difference of 116 nmol/liter (95% confidence interval, 52.54 to 179.37; P < 0.001), and one patient with a normal response on the SST had a subnormal cortisol response in the combined test. Similar lower peak cortisol responses were observed in males and females with combined test. The difference between the peak cortisol responses showed no significant correlation with age (r = 0.123; P = 0.58) or with the body mass index (r = -0.376; P = 0.09). There was no difference in GH measurements between the GHRH/arginine test done alone or in combination with the SST. CONCLUSIONS: Combining the SST and GHRH/arginine test results in a lower cortisol response to synacthen. For this reason, the combined test cannot be recommended to assess the integrity of cortisol and GH reserve using current diagnostic criteria.

Adrenocorticotropic Hormone↗
PubMed1978

Diagnosis of Sheehan's syndrome using a sequential pituitary stimulation test.

Systematic pituitary evaluation was performed in four patients suspected of having Sheehan's syndrome. A sequential pituitary stimulation test, consisting of insulin-induced hypoglycemia followed by stimulation of gonadotropin-(GnRH) and thyroid-releasing hormone (TRH), a metyrapone test, and adrenocorticotropic hormone (ACTH) stimulation test, was performed. All four patients failed to develop a normal increase in serum growth hormone, cortisol, and prolactin (PRL) following insulin-induced hypoglycemia. All patients demonstrated a blunted PRL, follicle-stimulating hormone, and luteinizing hormone response to the combination of GnRH and TRH. Although thyroid stimulating hormone (TSH) response was impaired in all patients, two patients had normal T3 resin uptake and thyroxine, demonstrating minimal TSH reserve maintaining normal baseline free thyroxine index. Metyrapone administration was followed by no increase in 11-deoxycortisol or 17-ketogenic steroids, thereby adding no additional information to the hypoglycemia stimulation. ACTH infusion revealed normal adrenal cortisol response. In conclusion, in patients with suspected postpartum hypopituitarism, a complete pituitary function investigation can be done in a short time by using the described pituitary sequential stimulation test.

Adrenocorticotropic Hormone↗
PubMed1977

Evidence for dopaminergic control of thyrotrophin secretion in man.

After administration of the dopamine-receptor-blocking drug, metoclopramide (10 mg orally), there is significant release of thyrotrophin (T.S.H.) in hypothyroid patients which is not evident in euthyroid subjects. This is not due to spontaneous fluctuation in basal T.S.H. levels, and it indicates inhibitory dopaminergic control of T.S.H. release in man. The lack of significant T.S.H. release in euthyroid subjects may be due to the inhibitory effects of normal circulating levels of T3 and T4 on T.S.H. release. The T.S.H. response in hypothyroidism is significantly correlated with both T3 and T4 levels, suggesting suppression of this inhibitory pathway in increasingly severe hypothyroidism.

Administration, Oral↗
PubMedDate not supplied

[Dwarfism due to familial panhypopituitarism].

Three sisters of 27 7/12, 13 8/12 and 9 1/12 years of age, respectively, with proportionate dwarfism, high pitched voice and lack of sexual development are described. All the patients had very low serum levels of immunoreactive growth hormone (GH), as well as of LH and FSH. Hypoglycemia induced by insulin and arginine infusion failed to increase GH levels, and the administration of the hypothalamic LH-FSH releasing hormone (LH-RH) did not elicit any response in the secretion of gonadotropins. The oldest sister developed hypothyroidism in recent years, since the I131 thyroid uptake was normal ten years before; her serum TSH was low and did not change with TRH stimulation. In addition, a low pituitary ACTH reserve was demonstrated by the hypoglycemia and metirapone tests. Case 2 showed partial pituitary TSH and ACTH reserve, whereas the youngest child only had low TSH pituitary reserve. These patients had all the clinical and laboratory characteristics of familial panhypopituitarism, with normal sella turcica. Genetic transmission in this cases is consistent with the autosomal recessive form, which is the most frequent type of inheritance of this entity. Consanguinity can not be ruled out. The results of the hypothalamic-pituitary functional tests apparently suggest that the primary defect could be located at the pituitary level. It is also possible that the pathological process may have a progressive evolution.

Adolescent↗
PubMed1987

[Results of the GnRH-TRH and arginine-GnRH-TRH test in females with hyperprolactinemic galactorrhea].

In 7 patients aged from 21 to 33 years (average age 24.6 years) with hyperprolactinemic galactorrhea a stimulation test with GnRH-TRH or arginine-GnRH-TRH was performed. The serum levels of LH, FSH, PRL, HGH, TSH and total thyroxine (T4) were determined by RIA, the thyroxine binding capacity (TBC) by radio agent assay. The free thyroxine index (FT4-I) was calculated. An adenoma of the pituitary gland was diagnosed in 3 patients by X-ray of sella turcica. In all patients there were disturbances of the menstrual cycle. Independent of the existence of an adenoma of the pituitary gland in all patients with high basal levels. PRL could not have been shown stimulated by TRH. On the other hand it could be shown that despite of high basal PRL-levels in serum there was a normal stimulation of the gonadotrophs in 5 patients. Out of one patient the stimulation of the thyreotropic cells of pituitary by TRH was normal, too, whereas there was no or an inadaquate stimulation of HGH by arginine in all patients.--T4, TBC and FT4-I showed no deviation from the normal range.

Adenoma↗
PubMed1997

Residual pituitary function after transsphenoidal hypophysectomy in dogs with pituitary-dependent hyperadrenocorticism.

Pituitary function was assessed before and after transsphenoidal hypophysectomy in 39 dogs with pituitary-dependent hyperadrenocorticism (PDH). Anterior pituitary function was investigated using combined administration of four hypophysiotropic releasing hormones (corticotropin-releasing hormone (CRH), GHRH, GnRH, and TRH) with measurements of ACTH, cortisol, GH, LH, prolactin (PRL), and TSH Pars intermedia function was assessed by measurements of basal plasma alpha-MSH concentrations and adrenocortical function by baseline urinary corticoid/creatinine ratios. At eight weeks after hypophysectomy basal plasma ACTH, cortisol, GH, LH, PRL, and TSH concentrations were significantly lower than before surgery. In seven dogs with elevated alpha-MSH concentrations, the values returned to the normal level after surgery. In the combined anterior pituitary function test there were no plasma GH, LH, PRL, and TSH responses to stimulation, whereas plasma ACTH and cortisol responses were small but significant. Remission of hyperadrenocorticism was obtained in 35 dogs and recurrences occurred in 3 of these within 16 months postoperatively. At 8 weeks after hypophysectomy, these 3 dogs were not discernible, with respect to residual pituitary and adrenocortical function, from the 32 dogs with persisting remission. Urinary corticoid/creatinine ratios in the latter group of dogs did not increase during 22 months after hypophysectomy. In contrast to the presurgical findings, at 8 weeks after hypophysectomy there were significant positive correlations between baseline urinary corticoid/creatinine ratios and basal levels and responses for ACTH, indicating return to normal function of the pituitary-adrenocortical axis. It is concluded that among the adenohypophyseal cells present in the sella turcica after hypophysectomy, the corticotropes have a distinct behavior. Much more so than the other cell types, the unaffected corticotropes tend to remain functional, or a repressed reserve fraction of corticotropes may become functional. This may be due to the removal of the hypothalamic influence of a postulated corticotropin-release inhibiting factor or a diminished inhibitory influence of a postulated paracrine factor. The corticotropes may maintain normocorticism, but may also lead to mild recurrence after relatively long periods of remission.

Adrenocortical Hyperfunction↗
PubMed1977

Serum prolactin in patients with "functionless" chromophobe adenomas before and after therapy.

The immunoreactive serum human prolactin (PRL) level was measured before and after intravenous administration of 500 mug of thyrotrophin-releasing hormone (TRH) in 11 patients with "functionless" chromophobe adenomas before and after surgery and after radiotherapy in 6 of these patients. The results were compared to other pituitary function tests. Two of the patients studied had recurrent disease after previous pituitary surgery and radiotherapy. Five patients had pituitary surgery through the transfrontal route, while 6 had adenoma removal via the transnasal transsplenoidal route. Before surgery, the serum PRL concentration was abnormally high in 4 patients, before and after TRH administration. It was normal in 6 and subnormal in 1 patient who had had previous therapy. Two of the patients studied showed high serum thyroid-stimulating hormone (TSH) levels in the presence of low serum T3 and T4 suggesting primary hypothyroidism with a secondary TSH-producing pituitary tumour. After surgery all patients showed a significant decrease of the serum PRL level. This contrasts with more variable results in the measurements of other pituitary hormones. Post-operative radiotherapy produced no significant additional change in serum PRL levels in 5 of the 6 patients measured 6 months to 4 years after radiotherapy. Five of the 6 patients who had adenoma removed via the transsphenoidal route required no cortisol replacement and 4 remained euthyroid, whereas all 5 patients after transfrontal surgery required both cortisol and thyroid hormone replacement. These results indicate: (1) that measurement of serum PRL levels at basal and after TRH administration in patients with "functionless" chromophobe adenomas before and after treatment may be the best index for evaluating the effect of therapy; (2) that adenoma removal may be followed by preservation of normal pituitary function, but this is more likely to occur if the transsphenoidal approach is used; and (3) that primary thyroid insufficiency may be associated with a pituitary adenoma.

Adenoma, Chromophobe↗
PubMed2000

Corticotropin- and thyrotropin-secreting pituitary microadenomas: detection by dynamic magnetic resonance imaging.

Hormone-secreting pituitary microadenomas are often not visible on magnetic resonance imaging (MRI). Diagnosis requires confirmatory endocrine test results and often an invasive procedure, inferior petrosal sinus sampling (IPSS). Improved pituitary imaging may eliminate the need for IPSS in some patients, as shown in the 2 women in this report. The first patient with hirsutism, weight gain, and hypertension had intermittent elevations of urinary free cortisol, abnormal results on a low-dose dexamethasone suppression test, and positive results on a dexamethasone-suppressed ovine corticotropin-releasing hormone test (corticotropin, increase of 122%; cortisol, increase of 118%). Gadolinium-enhanced MRI showed no focal lesion, but dynamic MRI (sequential images beginning immediately after contrast injection) revealed a right-sided 5-mm microadenoma, confirmed by transsphenoidal surgery. The second patient had a goiter, anxiety, increased free thyroxine and triiodothyronine levels, and a normal thyrotropin value with no response to thyrotropin-releasing hormone. Magnetic resonance imaging showed no lesion, but dynamic MRI detected an 8-mm microadenoma. Although about 8% to 10% of healthy persons have incidental pituitary lesions that are 3 mm or larger on MRI, identification of a distinct lesion and positive results on a dexamethasone-suppressed ovine corticotropin-releasing hormone test should decrease the probability of a false-positive result on an imaging study. We recommend that dynamic MRI be performed in any patient with a suspected microadenoma, before IPSS is performed.

Adenoma↗