1/71. Clinical and morphological features of undifferentiated monomorphous GH/TSH-secreting pituitary adenoma.A 41-year-old male presented with progressive visual defects, acromegaly and hyperthyroidism. After clinical evaluation a giant GH/TSH-secreting pituitary adenoma was diagnosed. Administration of the somatostatin analog octreotide at doses of 150 microg s.c. per day inhibited the secretion of both GH and TSH. A three-week treatment with octreotide prior to surgery led to slight visual improvement and CT scan showed some new necrotic areas within the tumor mass. Transcranial surgery was performed. By immunohistochemical analyses of the adenoma tissue GH, prolactin and beta-chorionic gonadotropin were detected; TSH was negative. Electron microscopy revealed an undifferentiated, monomorphous adenoma with morphological features of an acidophil stem cell adenoma such as the presence of misplaced exocytoses, fibrous bodies and mitochondrial gigantism. However, the tumor cells contained small secretory granules (up to 250 nm) accumulated along the cell membrane characteristic of thyrotrope cells. Furthermore, some adenoma cells were fusiform with long cytoplasmic processes resembling thyrotropes. Two months after the operation CT scan revealed a large residual tumor. serum GH and TSH levels had increased again and the TSH level was even higher than before the treatment. The patient died suddenly, most probably of lethal arrhythmia. Specimens of the adenoma tissue obtained at autopsy confirmed the previous findings with the exception of positive immunostaining for TSH which was found in less than 1% of the adenoma cells. This undifferentiated, monomorphous GH/TSH-secreting pituitary adenoma represents an entity that is unusual both in its ultrastructural features and clinical manifestations suggesting a cytogenesis from an early, undifferentiated stem cell.- - - - - - - - - - ranking = 1keywords = rhythm (Clic here for more details about this article) |
2/71. Receptor imaging with 111In-pentreotide and 123I-methoxybenzamide, and inhibition tests with octreotide and bromocriptine of mixed growth hormone/prolactin-secreting pituitary tumors.We have performed pituitary scintigraphy with 111In-pentreotide (OCT), a somatostatin analogue, and with metoxybenzamide (IBZM) by 123I-IBZM in two patients affected by mixed growth hormone/prolactin-secreting pituitary tumors. Short-term growth hormone (GH) inhibition by a single injection of OCT (100 micrograms s.c.), and short-term prolactin (PRL) inhibition by oral administration of 2.5 mg of bromocriptine (BCR), were also performed in both patients. The first patient, a 26 year old man, showed intense tumor uptake of 123I-IBZM scintigraphy, whereas 111In-OCT scintigraphy showed moderate tumor uptake. Five hours after the BCR inhibition test, a fall of 83% in PRL plasma levels (from 8,336 micrograms/L to 1,417 micrograms/L), and of 91.6% in GH plasma levels (from 39.5 micrograms/L to 3.3 micrograms/L) were observed. OCT inhibition test suppressed GH plasma levels from 36 micrograms/L to 3.5 micrograms/L. The patient was submitted to treatment with BCR and OCT. A dramatic shrinkage of the tumor was seen after six months of therapy. The lesion disappeared one year after the start of therapy. The second patient, a 64 year old man, showed intense uptake at 111In-OCT scintigraphy, while 123I-IBZM uptake was not observed. A test dose of BCR resulted in an acute fall of PRL (from 145 micrograms/L to 118 micrograms/L), but not of GH. A test dose of OCT decreased the GH plasma level from 61 micrograms/L to 4.5 micrograms/L. The patient was submitted to treatment with BCR and OCT that resulted in a computed tomography and magnetic resonance imaging decrease of 45% of tumor volume one year after the start of therapy. Our results suggest that both suppression tests with OCT and BCR, and scintigraphic studies in vivo with 123I-IBZM and 111In-OCT can be predictive for the effectiveness of therapies with dopamine agonists and/or SS-analogs in patients with mixed PRL/GH-secreting pituitary tumors. Further studies are required to evaluate the role of suppressive tests in selecting patients for appropriate clinical treatments.- - - - - - - - - - ranking = 0.0029205909971152keywords = hour (Clic here for more details about this article) |
3/71. High molecular weight corticotropin measured with immunoradiometric assay in a patient with asymptomatic pituitary corticotropinoma.A 57-yr-old female with corticotropinoma showing no Cushingoid stigmata is reported. Basal plasma levels of ACTH measured with immunoradiometric assay and beta-endorphin were high, 12.6-15.9 pmol/l and 3.5 pmol/l, respectively. plasma cortisol level and urinary free cortisol excretion were normal, 303-359 nmol/l and 171-226 nmol/day, respectively. plasma ACTH markedly increased to 70.5 pmol/l with intravenous administration of 100 microg CRH. Diurnal rhythm of plasma ACTH was seen, but its level in the night was still high. plasma ACTH suppression with dexamethasone was insufficient. CRH stimulation after dexamethasone suppression increased plasma ACTH level from 4.4 to 13.7 pmol/l. Intravenous administration of 4 microg desmopressin increased plasma ACTH from 15.6 to 19.6 pmol/l. Oral administration of 16 mg lepramide insufficiently decreased plasma ACTH from 7.3 to 5.3 pmol/l. However, plasma cortisol responses in these conditions were normal. Postoperative pathological study revealed subtype 1 corticotropinoma immunohistochemically and electron-microscopically. Postoperative basal plasma ACTH decreased to 3.9 pmol/l, although plasma cortisol did not change. Diurnal rhythm and dexamethasone suppressibility of plasma ACTH became normal. plasma sample was chromatographed on a Sephadex G-75 column. The elution profile showed two peaks of ACTH, one of which was compatible with 1-39 ACTH and another with higher molecular weight ACTH which was probably secreted from corticotropinoma. Anomaly in processing of proopiomelanocortin was suspected.- - - - - - - - - - ranking = 2keywords = rhythm (Clic here for more details about this article) |
4/71. pituitary apoplexy probably due to TRH and GnRH stimulation tests in a patient with acromegaly.pituitary apoplexy is the most serious and life-threatening complication of pituitary adenomas. Most of the cases occur spontaneously but it may occur also after a number of events such as the pituitary stimulation tests. We report a case of acromegaly due to a giant pituitary adenoma in which pituitary apoplexy developed 88 hours after TRH/GnRH stimulation test. The patient had severe headaches, nausea, vomiting, visual disturbance and mental alteration and the computed tomography (CT) scans revealed intratumoral and intraventricular bleeding. The pituitary mass was removed by transsphenoidal approach. The patient developed pneumonia and died on the 9th postoperative day. pituitary apoplexy was confirmed at surgery and on histological examination. Immunohistochemical staining was positive for GH and PRL. This case indicates that pituitary apoplexy may develop several days after TRH/GnRH stimulation test.- - - - - - - - - - ranking = 0.0029205909971152keywords = hour (Clic here for more details about this article) |
5/71. Transient headache and impaired vision after intravenous thyrotropin-releasing hormone in a patient with pituitary macroadenoma.We report a case of transient headache and impaired vision following administration of intravenous thyrotropin-releasing hormone (TRH) to a woman with a non-functioning pituitary macroadenoma, visual field defect, and elevated thyroid-stimulating hormone (TSH). The symptoms lasted for two hours and then resolved without known sequelae. There are a few other reported cases of similar adverse reactions to neuroendocrine manipulation in patients with pituitary macroadenomas. This is the second reported case of such adverse reactions to TRH alone and the first in which the patient had prior elevation of TSH.- - - - - - - - - - ranking = 0.0029205909971152keywords = hour (Clic here for more details about this article) |
6/71. gonadotropin-releasing hormone-induced partial empty sella clinically mimicking pituitary apoplexy in a woman with a suspected non-secreting macroadenoma.pituitary apoplexy has been reported as a rare complication of dynamic testing used for the study of pituitary functional reserve. In 1993, a diagnosis of non-secreting macroadenoma with moderate functional hyperprolactinaemia was made in a 43-year-old woman. Soon after the start of therapy with bromocriptine up to 5 mg/die, the patient complained of nausea and postural hypotension. As the symptoms persisted even when the dose was reduced to 2.5 mg/die, the patient was transferred to therapy with quinagolide at the dosage of 37.5 microg/die. PRL levels quickly normalized (range 1.4-5.7 ng/ml) as well as menstrual cycles, and no side-effect was reported. In 1995 a sellar magnetic resonance imaging (MRI) showed no shrinkage of the known macroadenoma. In 1996, few hours after a gonadotropin-releasing-hormone (GnRH) test, which showed normal LH and FSH response and with baseline PRL levels in the normal range, the patient started complaining of severe frontal headache, nausea and vomiting. No gross visual defects were present. An emergency computed tomography (CT) showed no evident hemorrhagic infarction in the macroadenoma. The symptoms completely resolved in few days with steroidal and antiemetic therapy. A new MRI performed in 1998 showed a partial empty sella and PRL levels were in the normal range under dopaminergic treatment. The pituitary functional reserve proved normal on dynamic testing. The temporal association between the onset of symptoms and the GnRH test strongly suggests an association between the two events. No evident signs of pituitary apoplexy (either on emergency CT or hormonal evaluation) were detected. The authors suggest that GnRH can cause severe side-effects that mimic pituitary apoplexy without related morphological evidence and that, in our particular case, it can have caused the gradual disappearance of the non-secreting macroadenoma. Moreover, a causal role of the chronic dopaminergic treatment cannot be completely ruled out.- - - - - - - - - - ranking = 0.0029205909971152keywords = hour (Clic here for more details about this article) |
7/71. octreotide improved ventricular arrhythmia in an acromegalic patient.We saw a remarkable effect of octreotide, the long-acting somatostatin analogue, in reducing the number of ventricular premature complexes (VPCs) in a 59-year-old woman with acromegaly. Her basal GH and IGF-1 levels were up to 22.9 ng/ml and 934.9 ng/ml respectively. MRI revealed a 14 x 12 x 10 mm mass lesion in the pituitary gland. She had hypertension and echocardiography showed an increase in left ventricular wall thickness. Electric cardiography showed the presence of frequent VPCs and 24-h Holter monitoring revealed 24,277 beats of multifocal VPCs/24 h. She was treated with 300 microg/day of octreotide for four weeks before transsphenoidal surgery. After octreotide treatment, GH and IGF-1 were suppressed to 1.8 ng/ml and 145.3 ng/ml respectively, and the tumor size was remarkably reduced. Furthermore, the number of VPCs was also dramatically reduced to 2062 VPCs/24-h (8.5% of pretreatment) with 24-h Holter monitoring. This case shows that VPCs of acromegalic patients can be controlled by suppressing GH and IGF-1 with octreotide, and this agent is useful for reducing both tumor size and frequency of VPCs prior to surgery.- - - - - - - - - - ranking = 4keywords = rhythm (Clic here for more details about this article) |
8/71. Apoplexy of pituitary macroadenoma after combined test of anterior pituitary function.pituitary apoplexy has been reported as a very rare complication of combined tests of anterior pituitary function and of TRH or gonadotropin-releasing hormone (GnRH) administration in pituitary tumor. A 34-year-old man with a GH-secreting pituitary macroadenoma and diabetes mellitus received an injection of 400 microg TRH, 100 microg GnRH, and 0.15 U/Kg regular insulin. Twenty minutes later, he complained of a severe headache and vomited. visual acuity and visual field did not change and his headache was persistent during the next 24 hours of conservative management. magnetic resonance imaging (MRI) of the sella turcica done the day after the event showed definitive elevation of the optic chiasm and slight enlargement of tumor and focal areas of mixed high signal and low signal intensities in the macroadenoma on noncontrast T1-weighted images. headache subsided markedly within a day of octreotide therapy. Transsphenoidal removal of the pituitary tumor was performed 9 days after the hormone study. Ischemic necrosis and hemorrhage were confirmed in the acidophilic adenoma with positive immunostaining for GH. Postoperative course was uneventful and his serum insulin-like growth factor-1 (IGF-1) level and blood glucose levels were normalized. Three months after the surgery the dynamic test was repeated without adverse effects. To our knowledge, this is a very rare case of apoplexy of GH-secreting pituitary adenoma after a combined stimulation test of anterior pituitary function.- - - - - - - - - - ranking = 0.0029205909971152keywords = hour (Clic here for more details about this article) |
9/71. Perioperative management of central diabetes insipidus in kidney transplantation.Central diabetes insipidus is clinically masked in dialysis patients. We report a 12-year-old girl receiving a living-related donor graft for renal failure from Alport syndrome, in whom a craniopharyngioma had been resected 6 months before transplantation. Pretransplant evaluation had documented central hypothyroidism, growth hormone deficiency, and presumptive hypogonadotropic hypogonadism. The corticotropin-releasing factor test had been normal. Four hours after transplantation, urine output exceeded 1,000 ml/h without diuretic therapy. serum sodium concentration was 155 mmol/l, serum osmolality 333 mmol/kg, and plasma antidiuretic hormone 4.9 ng/l, while urine osmolality was 233 mmol/kg. Desmopressin acetate was started by continuous intravenous infusion at 1 microgram/day. serum electrolytes rapidly normalized, urine output stabilized at 2 l/day. The patient was discharged 4 weeks after transplantation with good allograft function, receiving intranasal desmopressin acetate 10 micrograms twice daily. Pre-existing central diabetes insipidus is unmasked after successful kidney transplantation, leading to rapid dehydration and hypernatremia, which can be prevented by prompt institution of desmopressin therapy.- - - - - - - - - - ranking = 0.0029205909971152keywords = hour (Clic here for more details about this article) |
10/71. Significant gene expression of insulin-like growth factor ii and proliferating cell nuclear antigen in a rapidly growing recurrent pituitary acth-secreting adenoma.BACKGROUND: We quantified the expression of various growth-related factors in an adrenocorticotropic hormone (ACTH)-secreting adenoma that had recurred very rapidly as invasive macroadenoma. methods/RESULTS: A 43-year-old woman underwent successful transsphenoidal surgery for Cushing's disease. Seven years later, she was admitted to our ward for further endocrine examinations. In spite of a very high plasma ACTH level, the serum cortisol level was normal. Discrepancies between ACTH and cortisol levels were detected on the basis of diurnal rhythms, dexamethasone suppression tests, and corticotropin-releasing hormone test. The patient showed no clinical features of Cushing's disease. magnetic resonance imaging of the pituitary showed an almost empty sella, and no microadenoma was found. These results, along with those of Sephadex column gel filtration and high-performance liquid chromatography of plasma-immunoreactive ACTH, suggested that the patient's residual corticotrophs secreted biologically inactive ACTH. Two years later, the patient suddenly developed diplopia and right abducens nerve palsy. She was slightly moonfaced and centrally obese. Her plasma ACTH and serum and urinary free cortisol levels were elevated, although discrepancies between ACTH and cortisol still existed. magnetic resonance imaging revealed a large pituitary mass with suprasellar and cavernous sinus extensions. The tumor was excised, and the proopiomelanocortin gene and the expression of growth-related factors were analyzed. No mutations were found in the ACTH-coding region of the proopiomelanocortin gene. A significant expression of insulin-like growth factor II and proliferating cell nuclear antigen mRNAs was demonstrated. A high MIB-1 antibody labeling index was also detected in the adenoma tissue, suggesting high Ki-67 expression. CONCLUSION: These growth- and proliferation-related factors might be involved in the rapid growth and aggressiveness of this patient's pituitary adenoma.- - - - - - - - - - ranking = 1keywords = rhythm (Clic here for more details about this article) |
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