rav endocrinology pituitary- mksat

* Hypothalamic causes of pituitary dysfunction should be suspected when hypopituitarism is accompanied by diabetes insipidus or hyperprolactinemia.
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Hypopituitarism is commonly seen in patients after various brain injuries or insults, including traumatic brain injury, subarachnoid hemorrhage, neurosurgery, and cranial irradiation.

* Lymphocytic hypophysitis, which usually occurs during or after pregnancy, causes hypopituitarism, possible symptoms of a mass lesion, and often adrenocorticotropic hormone insufficiency.
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Adults with growth hormone deficiency have decreased muscle mass, increased fat mass, and decreased bone mineral density; many also have decreased strength, endurance, and well-being.

* A growth hormone stimulation test is necessary to diagnose growth hormone deficiency.
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In addition to prolactinomas, possible causes of hyperprolactinemia include medications, suprasellar lesions, hypothyroidism, renal failure, hypothalamic disease, and pregnancy.
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Hyperprolactinemia also may be due to decreased clearance of prolactin because of chronic renal failure and the presence of macroprolactin.
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Dopamine agonists, in particular cabergoline, are the primary treatment for patients with prolactinomas.

* Acromegaly carries a two- to threefold increased risk of mortality when levels of growth hormone and insulin-like growth factor 1 are not normalized.
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Long-acting preparations of the somatostatin analogues octreotide and lanreotide have been shown to reduce growth hormone and insulin-like growth factor 1 levels to normal in approximately 60% of patients with acromegaly but result in only modest reductions in tumor size.
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* Somatostatin analogues are effective as adjunctive treatment of patients with thyroid-stimulating hormone–secreting adenomas.
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Treatment of central diabetes insipidus includes desmopressin, which can be administered either orally via a metered nasal spray or subcutaneously by injection.
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Cushing syndrome during pregnancy is associated with a substantially increased risk of prematurity and stillbirth.

Causes of Hypopituitarism
Genetic defects
Hypothalamic hormone gene defects
Hypothalamic hormone receptor gene defects
Pituitary hormone gene defects
Pituitary hormone receptor gene defects
Transcription factor gene defects (affecting multiple pituitary hormones)

Embryopathies
Anencephaly
Midline cleft defects
Pituitary aplasia
Kallmann syndrome (anosmin gene defect)

Acquired defects
Tumors (pituitary adenomas, craniopharyngiomas, dysgerminomas, meningiomas, gliomas, metastatic tumors, Rathke cleft cysts)
Irradiation
Trauma (neurosurgery, external blunt trauma)
Infiltrative disease (sarcoidosis, Langerhans cell histiocytosis, tuberculosis)
Empty sella syndrome
Vascular (apoplexy, Sheehan syndrome, subarachnoid hemorrhage)
Lymphocytic hypophysitis
Metabolic causes (hemochromatosis, critical illness, malnutrition, anorexia nervosa, psychosocial deprivation)
Idiopathic causes