ABSTRACT
Although thyrotropin-secreting pituitary tumors are rather exceptional, the authors have studied 5 new cases from 1982 to 1988. This apparently growing pattern is due to a more accurate diagnosis because of new laboratory measurements: --Immunoradiometric assay (IRMA) of ultra-sensitive thyrotropin (TSH); --Radioimmunoassay (RIA) of free alpha subunit of TSH; --Molar ratio of free alpha subunit/TSH before and after TRH stimulation; --Morphologic assessment of pituitary adenoma by computed tomographic scanning and nuclear magnetic resonance imaging; --Characterization of thyrotropin-secreting cells by immunohistochemical technics and identification of secretion products in cultured cells. The authors illustrate these new topics with a case report harboring a partial resistance to thyroid hormones. A 6-month treatment with somatostatin analogue (SMS 201.995) is reported, before transphenoidal ablation of the adenoma.
Subject(s)
Adenoma/diagnosis , Hyperthyroidism/etiology , Pituitary Neoplasms/diagnosis , Thyrotropin/metabolism , Adenoma/complications , Adenoma/drug therapy , Adenoma/metabolism , Adult , Humans , Male , Octreotide/therapeutic use , Pituitary Neoplasms/complications , Pituitary Neoplasms/drug therapy , Pituitary Neoplasms/metabolismABSTRACT
Known since 1967 and usually familial, the syndrome of tissue resistance to thyroid hormones may take one of two different forms, depending on the receptors involved. When resistance affects both peripheral and pituitary receptors, plasma thyroid hormone levels are high despite the lack of thyrotoxicosis, thyroxine and triiodothyronine are ineffective, even in high dosage, and plasma TSH increases to explode under TRH. When resistance only affects pituitary receptors, there is moderate thyrotoxicosis with paradoxical and inappropriate TSH increase. Contrary to expectations, nuclear receptors to triiodothyronine are perturbed in only a few cases. Reduction of thyrotropic hyperfunction, which is the primary purpose of treatment, can be achieved with D-forms of thyroid hormones or with somatostatin and its derivatives.
Subject(s)
Receptors, Thyroid Hormone/metabolism , Thyroid Diseases/metabolism , Thyroid Hormones/metabolism , Humans , Somatostatin/therapeutic use , Syndrome , Thyroid Diseases/blood , Thyroid Diseases/drug therapy , Thyroid Diseases/genetics , Thyroid Diseases/physiopathology , Thyroid Hormones/blood , Thyrotropin/metabolism , Thyroxine-Binding Proteins/metabolismSubject(s)
Hyperthyroidism/diagnosis , Evaluation Studies as Topic , Humans , Methods , Thyroid Hormones/bloodABSTRACT
Ten months following a severe head injury, a 26-year-old man developed a syndrome of inappropriate secretion of antidiuretic hormone (ADH) with a grand mal seizure occurring after an increased intake of non alcoholic beverages. The water loading test was negative but the sorbitol infusion test was positive. In the basal state, plasma concentration of ADH was inappropriate to plasma osmolality. ADH has also been measured during dynamic tests (infusions of sorbitol and of normal saline; complete and partial water restriction; propranolol and diphenylhydantoin treatments). In spite of the poor sensitivity of these measurements when ADH concentrations are low, our results indicate that the plasma osmolality threshold at which ADH secretion is inhibited was probably reset at a level lower than normal.
Subject(s)
Craniocerebral Trauma/complications , Hyponatremia/etiology , Adult , Humans , Inappropriate ADH Syndrome/etiology , Inappropriate ADH Syndrome/physiopathology , Male , Seizures/etiology , Time FactorsABSTRACT
Plasma arginine-vasopressin (AVP) levels were measured by radioimmunoassay in 26 untreated myxoedematous patients and 27 healthy subjects. In 22 patients, in spite low osmolality AVP values were not significantly different from those found in controls, but they were considerably increased in 4 patients with severe myxoedema and very low osmolality. Statistical analysis showed negative correlation between AVP values and osmolality in the patients. On the other hand, no correlation was found between AVP values and aldosterone or plasma renin activity values. These results suggest inappropriate secretion of antidiuretic hormone in myxoedema.
Subject(s)
Arginine Vasopressin/blood , Hypothyroidism/blood , Aged , Aldosterone/blood , Female , Humans , Hyponatremia/etiology , Inappropriate ADH Syndrome/blood , Male , Middle Aged , Myxedema/blood , Osmolar Concentration , Radioimmunoassay , Renin/blood , Sodium/blood , Thyroid Hormones , Thyrotropin/bloodABSTRACT
24 Addisonian patients were compared to 27 healthy subjects. Radioimmunoassay of plasma antidiuretic hormone showed higher concentrations of Arginine-vasopressin (AVP) in Addisonians than in normals, in spite of lower natremia and plasma osmolality. Statistical analysis showed a negative correlation between AVP and osmolality in Addisonian patients. On the other hand, no correlation was found between AVP and cortisol, or AVP and PRA. These results suggested an inadequate secretion of antidiuretic hormone in Addison disease. Under substitutive treatment, glucocorticoids alone didn't completely lower AVP concentration which was only normalized after administration of mineralocorticoids.
Subject(s)
Addison Disease/blood , Arginine Vasopressin/blood , Addison Disease/metabolism , Adolescent , Adult , Aged , Female , Humans , Hydrocortisone/blood , Male , Middle Aged , Osmolar Concentration , Renin/bloodSubject(s)
Autoimmune Diseases , Hypothyroidism/immunology , Adult , Aged , Female , Humans , Male , Middle AgedABSTRACT
The signs of Sjögren's syndrome were systematically researched in 36 patients with hypothyroidism (myxoedema with atrophic thyroiditis in 32 cases, Hashimoto's thyroiditis in 4). In a quarter of these patients were noted separately submaxillary glands and/or parotids enlarged, buccal and/or lacrymal sicca syndromes, and antisalivaryy ducts antibodies. The histologic analysis of minor salivar glands revealed foci of lymphocytes and plasmocytes (grades 3 and 4 of Chisholm's classification) in 6 subjects. Similarities between the Sjögren's syndrome and the autoimmune thyroiditis were specified; their association in the same patients might be explained considering the genetic predisposition to these affections.
Subject(s)
Hypothyroidism/complications , Sjogren's Syndrome/complications , Adult , Aged , Female , Humans , Male , Middle Aged , Sjogren's Syndrome/diagnosis , Thyroiditis/diagnosis , Thyroiditis/immunologyABSTRACT
Diabetic ketoacidosis is an extremely rare manifestation of glucagonoma. We report such a case in a 72-year-old woman known to be diabetic for seven years. The patient was admitted with diabetic ketoacidosis and associated necrolytic migratory erythrema which suggested the diagnosis of glucagonoma. Plasma glucagon levels were increased (569 to 2298 pg/ml). A vascular tumor of the head of the pancreas without obvious hepatic metastases was visualised by angiography. Duodeno-pancreatectomy including the head of the pancreas led to complete recovery of the mucocutaneous lesions and the plasma glucagon level fell (229 pg/ml). The tumor had several histological characteristics suggesting malignancy and a high glucagon content on extraction. Electron microscopy showed multiple A cells and a few isolated B cells. Most of the cells showed immunoreactivity with anti-glucagon and anti-glicentine antibodies. Three months after surgery, the diabetes was again required treatment with insulin. Plasma glucagon level was again increased and chemotherapy with dimethyltriazenimidazolecarboxamide was undertaken.
Subject(s)
Adenoma, Islet Cell/complications , Diabetic Ketoacidosis/complications , Glucagonoma/complications , Pancreatic Neoplasms/complications , Aged , Blood Glucose/metabolism , C-Peptide/blood , Female , Glucagon/blood , Glucagonoma/surgery , Humans , Pancreatic Neoplasms/surgerySubject(s)
Fasting , Obesity/metabolism , Thyroid Hormones/metabolism , Adult , Female , Humans , Male , Middle Aged , Thyroid Hormones/bloodABSTRACT
Computed tomography, a non-invasive procedure, is a major contribution for morphological exploration of pituitary adenomas extending into the suprasellar region, while, as the authors have demonstrated, it is still difficult to detect intrasellar adenomas, particularly microadenomas.