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 631 records · Page 35Linked to original sources

Gigantism in sibling unrelated to multiple endocrine neoplasia: case report.

The cases of gigantism sisters with somatotroph adenomas unrelated to multiple endocrine neoplasia (MEN) Type 1 are reported. The sisters grew rapidly since they were 5 or 6 years old and were diagnosed to have gigantism with pituitary adenoma by computed tomographic scan and magnetic resonance imaging. A serum endocrinological examination showed the elevated growth hormone values. After thyroxine-releasing hormone stimulation, growth hormone values exhibited a paradoxical rise. They were supposed to be unrelated to MEN Type 1, because analysis of the 11th chromosomes and the other endocrine functions were normal. They were operated on by the transphenoidal method. Immunohistochemical staining of both tumor specimens confirmed somatotroph adenomas. Pituitary adenoma associated with MEN Type 1 is a well-recognized entity. However, the sporadic occurrence of pituitary adenoma unrelated to MEN Type 1, especially in siblings, is extremely rare. Fifteen cases of pituitary adenomas in siblings were described in the literature. As for gigantism, only two brothers were reported. Our case of gigantism sisters is the second sporadic case. In our review of the isolated cases of pituitary adenoma in siblings described in the literature, 12 (70%) of 17 cases including ours are acromegaly or gigantism. This incidence is much higher than that of MEN Type 1 patients with pituitary adenomas. The cause of the familial occurrence of pituitary adenomas is still unclear, although autosomal recessive inheritance has been suggested. It has been stated that point mutations in codon 201 or 227 of the Gs alpha gene located in chromosome 20 were found in about 35 to 40% of somatotroph adenomas.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗

Surgical treatment of craniopharyngiomas: an evaluation of the transsphenoidal and pterional approaches.

Fifty-seven patients with craniopharyngiomas underwent a total of 64 operations. Their clinical follow-up ranged from 2.5 to 15.5 years, with a mean follow-up of 6.5 years. A transsphenoidal approach was used in 35 patients (61%), whereas 22 (39%) were operated on using a pterional approach (in 16 patients, the tumor was found in the suprasellar cisterns, and in 6, the tumor was found in the third ventricle and was removed passing through the lamina terminalis). Total removal of the tumor was achieved in 43 patients (75%). In six patients (11%), fragments of the capsule remained attached to the hypothalamus (subtotal removal), and, in eight patients (14%), the tumor was partially removed. No recurrence occurred in those patients in whom removal was total. Regrowth was observed in two patients (33%) in whom removal was subtotal and in two (25%) in whom removal was partial. Three of them underwent subsequent operations, and a total removal with good clinical outcome was achieved. All patients except two had good postoperative recovery. Twenty patients (35%) required hormonal replacement therapy. When transsphenoidal surgery was used, a total removal of the tumors was achieved in 23 (66%) of the patients. Good clinical outcome was seen in all 35 patients. Six patients (17%) required hormonal replacement therapy. When the pterional approach was used for tumors in the suprasellar cisterns, we achieved total removal of tumors in 15 patients (94%). Good clinical outcome was seen in 20 patients (91%). Eleven patients (50%) required hormonal replacement therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Radiation tolerance of functioning pituitary tissue in gamma knife surgery for pituitary adenomas.

OBJECTIVE: This study is intended to contribute to a determination of the sensitivity of preserved hypophyseal function to focal radiation in pituitary adenomas. METHODS: We compared two subgroups of patients followed up for a median of 5 years after gamma knife surgery (GKS). Subgroup 1 (n = 30) showed postirradiation hypopituitarism. Subgroup 2 (n = 33) was continually eupituitary. These subgroups were taken from a previously published study relating to a larger group of 163 patients with pituitary adenomas treated by GKS and evaluated after a median follow-up period of 2 years. A relatively high treatment dose was used in this larger group (median, 20 Gy to the tumor margin for growth control in nonfunctioning adenomas; median, 35 Gy for hypersecreting adenomas). Early results approached those of microsurgery, and there were only a few side effects. In the present study, we compared 16 different variables in the same two subgroups to discover the relationships that caused a delayed appearance of postirradiation hypopituitarism. The main pretreatment and treatment parameters were measured on reconstructed treatment plans. This database was used for statistical evaluation. RESULTS: The relationship between the mean dose and the volume of functioning hypophysis was stronger in terms of worsening of pituitary function than that of the spot dose to different intrasellar structures. We found that for our group of patients, the safe mean dose of radiation to the hypophysis was 15 Gy for gonadotropic and thyrotropic functions and 18 Gy for adrenocorticotropic function. The worsening of pituitary function was also significantly dependent on the dose to different anatomic levels of the infundibulum, but we did not succeed in fully characterizing this relationship. In addition, we discovered significant levels of dependency of postirradiation pituitary damage to different pretreatment and treatment variables. CONCLUSION: Knowledge of the radiation tolerance of functioning pituitary structures subjected to GKS can ensure better preservation of pituitary function after irradiation. This is valid for the group of patients we studied. Our study's findings can be used as a guideline for GKS treatment of new patients with pituitary adenomas, and it can serve for comparison with the experience of other gamma knife centers.

Adenoma↗

Panhypopituitarism caused by solitary parasellar metastasis from lung cancer.

Clinical panhypopituitarism caused by cancer with parasellar metastasis and hypothalamic invasion is very rare. This report concerns a lung cancer patient who had solitary parasellar metastasis with diabetes insipidus and panhypopituitarism as an initial manifestation, which was documented by contrast-enhanced computed tomographic scan, Gd-DTPA-enhanced magnetic resonance imaging, and endocrinologic studies.

Adenocarcinoma↗

[A study on the regulatory mechanism of hypothalamo-hypophyseo-ovarian system in estrous cycles of rats: Changes in responsiveness of the anterior pituitary gland to synthetic LH-RH (author's transl)].

It is generally accepted that the sexual cycle in mammals is accomplished by the systematic coupling of components of the hypothalamo-hypophyseo-gonadal system. However, how these components are related to each other to develop the sexual cyclicity has not yet been clearly established. A gonadotropin releasing factor (GnRF), which has been extracted and purified from porcine hypothalamus and whose molecular structure was determined in 1971, has been synthesized in many laboratories. The synthetic GnRF, named LRF or LH-RH, has gonadotropin releasing activity for many species of mammals, including humans. The debut of the synthetic LRF has given us a pure material and a direct means of stimulating, relatively easily, the gonadotroph cells in the anterior pituitary glands. In the present study, variations in the gonadotropin releasing activity of the pituitary gland in relation to synthetic LRF was investigated throughout the sexual cycle of rats. The relationship between pituitary sensitivity and levels of steroid hormones in the blood is discussed.

Animals↗

[Dopaminergic control of gonadotropin secretion in male senescence].

To verify the role of the dopaminergic mechanism in the control of gonadotropin secretion and aging of this mechanism in men, we studied serum gonadotropin response to LH-RH (100 micrograms i.v.) in basal condition and during dopamine infusion (DA 4 micrograms/kg/min). Seven young males (24-29yr.) and twenty aged males (50-80yr.) without endocrinological diseases were included in the present study. Aged male subjects were divided into hyperresponders, in whom maximal LH response to LH-RH without DA infusion exceeded 153.5mIU/ml (mean + 2SD of young male subjects), and non-hyperresponders, in whom maximal LH responses to LH-RH without DA infusion were less than 153.5mIU/ml. In hyperresponders, serum LH response at 30 minutes after LH-RH administration was significantly (p less than 0.05) suppressed by DA infusion. In non-hyperresponders and young male subjects, however, serum LH response to LH-RH was not affected by DA infusion. Basal levels of serum LH and FSH in hyperresponders tended to be higher than that of non-hyperresponders. Total serum testosterone, free testosterone and estradiol levels of hyper and non-hyperresponders failed to reveal any significant differences. These observations suggest that 1) DA directly suppresses gonadotroph responsiveness to LH-RH, 2) in aging men, inhibitory tone imposed on gonadotrophs by DA is decreased, and 3) this decline of DA system can cause hypergonadotropism in aging men, independent of serum sex steroids levels.

Adult↗

Manifestation of subclinical diabetes insipidus due to pituitary tumor during pregnancy.

We describe a case of diabetes insipidus (DI) due to a pituitary tumor in a 33-year-old pregnant woman who developed a sudden onset of polyuria (over 8 l/day) and polydipsia at 30 weeks of gestation. Her plasma concentration of vasopressin (AVP) was low compared with high serum osmolality (298 mOsm/kg), and her urine output was well controlled by treatment with desmopressin acetate (DDAVP). Cranial magnetic resonance imaging (MRI) demonstrated a 1.8 x 1.2-cm pituitary tumor, but she did not have any disturbance in the release of anterior pituitary hormones. The serum concentration of cystine aminopeptidase (CAP) was within the normal range for a woman at 34 weeks of gestation. After an uncomplicated delivery of a healthy girl, her polyuria gradually resolved. The size of the pituitary tumor gradually decreased in parallel to a reduction in her urine output, but a silent hemorrhage was detected in her pituitary gland 4 weeks after the delivery. Although pregnancy is sometimes associated with central DI, the occurrence of DI due to pituitary tumor under pregnancy is rare. The basal AVP recovered to within the normal range, but the low response of AVP secretion to high osmolality persisted. In this case, pregnancy may affect the manifestation of subclinical DI. This case may therefore enhance our understanding of the mechanisms of DI during pregnancy.

Adenoma↗

A case of lymphocytic infundibuloneurohypophysitis showing diabetes insipidus followed by anterior hypopituitarism associated with thrombasthenia.

We report a case of a 42-year old male patient with diabetes insipidus followed by anterior hypopituitarism associated with thrombasthenia. The patient had been diagnosed with thrombasthenia since the age of 19. He was admitted and diagnosed as diabetes insipidus in 1995. Although T1-weighted image of magnetic resonance imaging (MRI) showed empty sella and partial pituitary stalk hypertrophy, the anterior pituitary functions were normal at that time. Three years later, he was re-admitted after an episode of general malaise and impotence in 1998. Endocrinological studies revealed adrenal insufficiency, hypothyroidism and hypogonadism. T1-weighted image of MRI demonstrated the thickening of pituitary stalk and neurohypophysis. Analysis of anti-pituitary antibodies by immunoblotting identified a major band at 61.5 kDa. The diabetes insipidus was controlled by desmopressin acetate and the shrinkage of pituitary stalk was seen after hormonal replacement therapy including glucocorticoid and thyroid hormone. We suggested that this case represented lymphocytic infundibuloneurohypophysitis, in which a chronic inflammatory process occurred in infundibulum and/or neurohypophysis and that hypopituitarism developed possibly due to damage to the pituitary portal vessels caused by a thickened pituitary stalk, although a pituitary biopsy was not done because of the risk of bleeding in thrombasthenia. The pituitary autoantibodies in sera from patients with hypopituitarism may be helpful to characterize the patient with lymphocytic hypophysitis.

Adult↗

Correlation between the pituitary size and function in patients with asthenia.

To explore the relationship between pituitary morphology and function, we performed mid-sagittal MRI and endocrinological evaluation in 38 patients with asthenia. Six patients were diagnosed as having complete empty sella (ES) and 16 patients partial empty sella (PES). BMI, blood pressure, serum Na, ACTH, cortisol, TSH and T(4) were lower in ES group and PES group than in the group with normal pituitary size. Age in the patients with ES was oldest. Multiple regression analysis revealed that serum cortisol level was independently correlated with the size of the pituitary (beta = 0.586, p = 0.0069). Other variables, including age, BMI, blood pressure, serum Na, ACTH, TSH and T(4), were not correlated with the pituitary size when multivariate analysis was employed. In conclusion, there is a close relationship between the reduction of size of pituitary gland and the degree of adrenocortical dysfunction in asthenic patients. It is suggested that the pituitary-adrenal axis is especially vulnerable in empty sella syndrome, and therefore, meticulous evaluation of the hypophysial adrenal axis is recommended in subjects with reduced pituitary size even in elderly population.

Adrenal Insufficiency↗

Longitudinal study of patients with idiopathic isolated TSH deficiency: possible progression of pituitary dysfunction in lymphocytic adenohypophysitis.

The relationship between isolated TSH deficiency and hypophysitis was studied. Six patients (five women and one man) with idiopathic isolated TSH deficiency were longitudinally investigated with an interval of 31 to 60 months. Clinical symptoms, laboratory results and endocrine function were investigated as well as pituitary magnetic resonance imaging (MRI) at the start and the end of the study. Clinically, initial symptoms due to hypothyroidism were ameliorated by the thyroid hormone replacement in all patients. Oligomenorrhea newly appeared during the study in three patients, although no other symptoms appeared. Serum fT3 and fT4 levels were within the reference ranges, and serum TSH level and its response to TRH stimulation remained low in all patients. Peak plasma GH level during GRH stimulation was significantly (p<0.03) decreased, at the end of the study as compared with the start. Peak plasma FSH level to LHRH stimulation was significantly (p<0.03) decreased as well as basal FSH level. In contrast, peak of prolactin during TRH stimulation was significantly (p<0.03) increased at the end of the study as compared with the start as well as basal prolactin level. Endocrine features at the end of the study were compatible with those of lymphocytic adenohypophysitis (LAH). MRI of the pituitary gland showed empty sella in one patient and slight swelling in two patients. These findings remained unchanged during the study period. One patient underwent pituitary biopsy, with histological examination showing atypical form of LAH. LAH can cause idiopathic isolated TSH deficiency and can functionally progress to combine dysfunction of the pituitary gland.

Adult↗

Interstitial pituitary irradiation with 90Y for the treatment of acromegaly. A reappraisal.

The management of 54 acromegalics referred to us between 1974 and 1978 has been analysed. Twenty-two patients were treated with pituitary implants of yttrium-90 (90Y). Eleven are in complete remission (mean growth hormone (GH) less than 11 mIU/l), 8 had improved (mean GH 11-20 mIU/l or 50% less than preoperatively) and 3 were poor responders. Two patients had temporary 6th nerve paresis. Seven patients are on replacement therapy. Thirty-one patients were not implanted for the following reasons with a number of patients having more than one: extension of the tumour into the sphenoid sinus 10, or above the sella 3, partially empty sella 9, internal carotids too close to midline 2, invisible landmarks 1, mild acromegaly 6, poor general health 3, declined investigations or operation 6. It is concluded that pituitary implant of yttrium is an effective and safe form of treatment in carefully selected patients.

Acromegaly↗

Probable ACTH-secreting pituitary tumour in association with Addison's disease.

A 61 year old Japanese man with a diagnosis of Addison's disease was admitted to Kyushu University Hospital for further investigation of high ACTH levels and hyperpigmentation which 37.5 mg of cortisone acetate failed to alleviate. The basal level of plasma ACTH was 700-1000 pg/ml, and following 25-37.5 mg cortisone acetate or 1 mg dexamethasone the levels were 300-600 pg/ml. The general pigmentation showed little improvement with such medication. Radiographic studies revealed a double floor of the sella turcica and cisternal herniation. These observations suggested the existence of a pituitary ACTH-secreting tumour. Plasma ACTH showed a circadian rhythm ranging from 440 to 1570 pg/ml and it was not suppressed to a normal range by oral administration of dexamethasone, 8 mg/day or by continuous infusion of dexamethasone, 1.25 mg/h for 2 h. Plasma ACTH responses of 80% above basal level to lysine-vasopressin (LVP), and 12% above basal to synthetic ovine corticotrophin releasing factor (CRF) were observed. FK 33-824, a methionine-enkephalin analogue, suppressed plasma ACTH to 85% of basal level, while bromocriptine (CB-154) caused no significant change. These findings led to a diagnosis of pituitary ACTH-secreting adenoma (corticotropinoma) in association with Addison's disease. The persistent circadian rhythm of plasma ACTH suggested that this adenoma may not be completely free from regulation by the central nervous system. This case may be clinically significant for investigation of the pathogenesis of pituitary adenoma, particularly in Nelson's syndrome.

Addison Disease↗

Primary hypophysitis: clinical-pathological correlations.

OBJECTIVE: Primary hypophysitis comprises of three distinct histomorphological entities: lymphocytic, granulomatous and xanthomatous. Clinical features of the three subtypes for diagnostic and treatment strategies have yet not been well characterized. METHODS: Endocrine function, visual fields and acuity as well as magnetic resonance imaging characteristics were assessed before and after transphenoidal surgery in the largest series of 31 patients with primary hypophysitis (21 lymphocytic, 6 granulomatous, and 4 xanthomatous cases). RESULTS: Only lymphocytic hypophysitis occurred during pregnancy (30%) and was associated with other autoimmune diseases (24%). Visual fields and acuity abnormalities were not seen in xanthomatous hypophysitis. Lymphocytic and granulomatous hypophysitis most often resulted in severe dysfunction of the adrenal, gonadal and thyroidal axes as well as diabetes insipidus. For patients presenting with xanthomatous hypophysitis most often, mild anterior pituitary axis failure was documented and posterior pituitary involvement was hardly found. The outcome after transphenoidal biopsy was generally favorable. Pre- or postsurgical glucocorticoid treatment was very effective in 75% of the lymphocytic form in reducing the pituitary size. In contrast, glucocorticoid therapy was less effective in granulomatous or xanthomatous hypophysitis. CONCLUSION: Diffuse destruction of the complete pituitary gland including the infundibulum has to be considered in lymphocytic and granulomatous hypophysitis, whereas in xanthomatous, a circumscribed anterior pituitary lesion leading to compression of the pituitary gland without alteration of the pituitary stalk and optic chiasm can be assumed.

Adult↗