Internal Medicine Flashcards
pituitary adenomas
microadenoma
hyperprolactinemia definition
excess prolactin release results in galactorrhea-amenorrhea syndrome
hyperprolactinemia etiology
physiologic causes: pregnancy, early nursing, hypoglycemia, seizure, exercise, stress, sleep, nipple stimulation; prolactinoma; block of pituitary stalk and dopamine by tumors, cranippharyngioma, meningioma, dysgerminoma, empty sella, trauma; pharmacologic causes: dopamine synthesis blockers (phenothiazines, metoclopramide), dopamine-depleting agents (methyldopa, reserpine), tricyclics, narcotics, cocaine, SSRIs, risperidone; also high TRH due to primary hypothyroidism stimulates prolactin (always check TSH)
hyperprolactinemia clinical presentation
women: galactorrhea, menstrual abnormalities, osteoposoris, osteopenia, infertility, gynecomastia
hyperprolactinemia diagnosis
exclude pregnancy, lactation, hypothyroidism and medications
hyperprolactinemia management
1st line: cabergolide or bromocriptine (reduces prolactin to <10% of pre-treatment levels)
acromegaly etiology
GH-secreting pituitary adenomas (75% are macroadenomas); rarely ectopic GH or GHRH-secreting tumors
acromegaly clinical presentation
enlargement of hands and feet, coarse facial features, thick skin folds; shoe, hat, glove, ring size increase; prognathism and separation of teeth; deeper voice; increased sweating; obstructive sleep apnea; visceromegaly, osteoarthritis, entrapment neuropathy; menstrual problems (prolactin is co-secreted); 30% get cardiac pathologies (cardiomyopathy, hypertension, arrythmia, hypertrophy, diastolic dysfunction, premature atherosclerosis); impaired glucose tolerance (80%), diabetes (13-20%), hypertension (33%), joint disease (articular cartilage proliferation)
acromegaly diagnosis
Initial test: IGF-1 levels
acromegaly management
1st line –> surgery
acromegaly complications
tumor pressure or rupture into brain or sinuses
hypopituitarism etiology
Tumors:
hypopituitarism presentation
defficiencies in order
hypopituitarism diagnosis
measure hormones:
hypopituitarism management
treat underlying cause; hormone replacement therapy specially cortisol
Empty sella syndrome (ESS)
herniation of suprasellar subarachnoid space through diaphragm; no pituitary seen on MRI or CT; can be idiopathic or secondary to trauma or radiotherapy; presentation: obesity, multiparoous women, headeache and 30% will have hypertension; therapy is reassurance.
diabetes insipidus definition
disorder of the neurohypophyseal system (hypothalamus or neurohypophisis) results in ADH deficiency (central DI); or renal resistance to the action of ADH (nephrogenic DI)
central diabetes insipidus etiology
neoplastic/infiltrative lessions in hypothalamus or pituitary (60% have adenohypophisis deficiency):
nephrogenic diabetes insipidus etiology
Demeclocycline
diabetes insipidus presentation
polyuria, polydipsia, hypernatremia, urine specific gravity <1,010, severe dehydration, weakness, fever, altered mental state, prostration, nocturia
diabetes insipidus diagnosis
plasma/urine osmolarity ratio falls to the right of shaded area
diabetes insipidus differential
primary polydipsia
diabetes insipidus management
CDI: ADH hormone replacement or ADH secretion stimulators (chlorpropamide, clofibrate, carbamazepine)
SIADH etiology
cancer: small cell lung CA, pancreas CA, ectopic ADH secretion
