RESUMEN
There has been accumulating evidence that pituitary adenomas which cause Cushing's disease are located not only in sella turcica but also in various extrasellar and intracranial regions. We describe a case of Cushing's disease caused by a supra- and extrasellar ACTH-producing microadenoma, which originated in the anterior pituitary and extended upward without connecting to the stalk. The pituitary microadenoma was identified and removed by transsphenoidal microsurgery. After the surgery the patient experienced complete remission. This type of pituitary microadenoma is considered to be rare, but in order to accomplish successful surgical treatment, it is necessary to consider that pituitary adenomas which cause Cushing's disease may be located in such an unusual position.
Asunto(s)
Adenoma/complicaciones , Síndrome de Cushing/etiología , Neoplasias Hipofisarias/complicaciones , Adenoma/diagnóstico , Adenoma/cirugía , Hormona Adrenocorticotrópica/análisis , Adulto , Síndrome de Cushing/sangre , Femenino , Humanos , Inmunohistoquímica , Imagen por Resonancia Magnética , Microcirugia/métodos , Invasividad Neoplásica , Adenohipófisis , Neoplasias Hipofisarias/diagnóstico , Neoplasias Hipofisarias/cirugía , ReoperaciónRESUMEN
Vasopressin (VP) hypersecretion is known to occur in diabetes mellitus. Using magnetic resonance (MR) imaging, we evaluated the VP content of the posterior lobe of the pituitary gland in 22 patients with uncontrolled noninsulin-dependent diabetes mellitus. The mean VP level and hemoglobin A1c value were elevated; 6.8 +/- 6.8 pg/mL (normal, 0.3-3.5) and 11.7 +/- 2.1% (normal, < 6%). The signal intensity ratio of the posterior lobe to the pons was calculated on a MR T1-weighted image where the signal intensity reflects VP content and the posterior lobe has a characteristic hyperintense signal under normal conditions. The mean signal intensity ratio (1.34 +/- 0.22) was lower than that in 20 healthy subjects (1.56 +/- 0.13; P < 0.01). In 7 cases, the signal intensity ration was markedly decreased, and the hyperintense signal was absent. The hyperintense signal appeared after diabetic control in all 6 subjects who underwent follow-up MR examinations within 1-2 months. The VP content in the posterior lobe was decreased in patients with uncontrolled diabetes mellitus, which was thought to be caused by persistent VP hypersecretion. The persistent elevation of plasma VP might have some role in the initiation and progression of diabetic complications.
Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Neurohipófisis/metabolismo , Vasopresinas/sangre , Vasopresinas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Diabetes Mellitus Tipo 2/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neurohipófisis/patología , Valores de ReferenciaRESUMEN
We treated a diabetic patient with familial multiple endocrine neoplasia type 1 (MEN 1) who had undergone total pancreatoduodenectomy. The patient received insulin and showed signs of symptomatic primary hyperparathyroidism (PHPT). The insulin requirement to control blood glucose before and after parathyroidectomy was compared by using an artificial pancreas. The insulin infusion rate during the day and at night was reduced to about one-third and half, respectively, after parathyroidectomy with autotransplantation of parathyroid tissues into the forearm. The daily insulin dose was reduced from 36 units to 14 units 2 weeks after surgery, and glycemic control showed further improvement 2 months after surgery with the same dose of insulin for up to 6 months. These observations suggest that insulin sensitivity increases after surgical correction of PHPT.
Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus/tratamiento farmacológico , Insulina/farmacología , Neoplasia Endocrina Múltiple Tipo 1/cirugía , Paratiroidectomía , Adulto , Complicaciones de la Diabetes , Diabetes Mellitus/sangre , Femenino , Humanos , Insulina/administración & dosificación , Insulina/uso terapéutico , Sistemas de Infusión de Insulina , Neoplasia Endocrina Múltiple Tipo 1/sangre , Neoplasia Endocrina Múltiple Tipo 1/complicaciones , PancreaticoduodenectomíaAsunto(s)
Ácido 4,4'-Diisotiocianostilbeno-2,2'-Disulfónico/análogos & derivados , Proteína 1 de Intercambio de Anión de Eritrocito/fisiología , Cloruros/metabolismo , Sulfatos/metabolismo , Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-disulfónico/análogos & derivados , Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-disulfónico/farmacología , Animales , Proteína 1 de Intercambio de Anión de Eritrocito/antagonistas & inhibidores , Proteína 1 de Intercambio de Anión de Eritrocito/genética , Transporte Biológico Activo/efectos de los fármacos , Transporte Biológico Activo/fisiología , Cloruros/farmacología , Relación Dosis-Respuesta a Droga , Eritrocitos/metabolismo , Expresión Génica , Ratones , Oocitos/metabolismo , Xenopus laevisRESUMEN
Three types of cloned cDNA sequences for rat low molecular weight prekininogens were isolated and determined by molecular cloning and sequence analysis. The deduced amino acid sequences indicated that one, termed K-prekininogen, represents the counterpart of the known low molecular weight prekininogen present in other mammals, while the other two, called T-prekininogens, contain a novel T-kinin sequence which was recently identified from rat plasma. Although T- and K-prekininogens are highly homologous with each other, both of the T-prekininogens contain methionine, instead of arginine or lysine, as an amino acid preceding T-kinin and exhibit two consecutive amino acid deletions in the preceding region of T-kinin as compared with K-prekininogen. The former finding accounts for the previous observation of strong resistance of T-kininogens to cleavage with trypsin or kallikreins, while the latter finding has been explained by the structural analysis of genomic clones in which T-kinin-coding exon is contracted at its intron junction. A partial nucleotide sequence reported recently for the rat major acute phase protein (alpha 1-MAP) mRNA was found to be extremely related to the corresponding portion of the rat T-prekininogen mRNA. Furthermore, consistent with the previous report of the structural identity of major acute phase protein and alpha 1-cysteine proteinase inhibitor, kininogen closely resembles not only the former but also the latter in the amino acid compositions. The interrelationship among the triad of these proteins has been discussed.