Acromegaly and prolactinoma Flashcards
Why does acromegaly cause amenorrhea and galactorrhea
- GH stimulates prolactin R (Jak/stat)
- GH adenoma may cosecrete prolactin
- acromegalic tumor mass pushes on pit stalk and blocks dopamine
causes of carpel tunel
MEDIAN TRAP M-myxedema edema DM infiltration amyloid neoplasms trauma RA acromegaly pregnancy
acanthrosis nigricans
d/t stimulation of IGF1
what is a normal glucose suppression test
must suppress GH to less then 1ng/mL
or less then /4 with ultrasensitive GH assays
GH on meta
lipolysis
gluconeogenesis
lactate -> glycerol -> glucose
GH is a slow acting counter regulatory hormone like cortisol
what syndromes are associated with acromegaly
MEN 1
Carney complex
MuCune-albright syndrome
MEN1
parathyroid hyperplastic -> hypercalcemia
pituitary adenoma -> GH and/or pancreatic endocrine tumor -> ZE syndrome
Carney complex
mutation in tumor suppressor gene for protein kinase A GH secreting pituitary tumor spotty skin myxomas testicular tumors
associated complications with GH secreting adenoma
mass effects additional hormones (PRL, TSH) interference with other hormones (decreased ACTH, TSH)
goals of acromegaly Tx
GH <.4
increased PRL
decreases GNRH -> decreases LH which decreases E -> decreased sex hormone binding globulin-> increased free T -> hirsutism and acne
endocrine causes of hyperprolactinemia
pituitary adenoma
hypothalamic disese
hypothyroidism
pregnanacy
drugs which can cause hyperprolactinemia
CNS acting meds (hydroxyzine) anti HTNs (verapamil) sex hormones certain H2 blockers metoclopromide protease inhibiotrs opiates
other causes of hyperprolactinemia
cirrhoiss exercise macroporlactinemia (IgG binding) nipple stimulation REM sleep renal failure SLE stress
HIGH PROLACTINS
HTN meds infiltrative disease GH hypothyroidism, H2 blockers pregnant/postpartum, PIs, macroProlactinemia renal failure, reglan oral contraceptives, opiates liver disease adenoma of pit, empty sella craniophayrngiomas tranquilizers, tricclics, truama, tumor idiopathic nipple stimulation stress, sleep, seizures, surgery, SSRIs, SLE, MS, sexercise
type IV RTA
loss of aldosterone effect on kidney
hyperchloremic, hyperkalemic, acidosis
normal to mild elevation of anion gap
PRL >200
look for prolactinoma
what are the symptoms of prolactinomas in males
loss of libido
impotence
bitemporal hemianopsia
macroprolactinemia
patients have PRL >200, with neg MRI and no symptoms
precipitate IgGs with polyethylene glycol, then remeasure PRL
PPCM
prolactin mediated postpartum cardiomyopathy
what order are hormones lost in pituitary insufficiency
GH
GN
TSH
ACTH
GH loss
fine wrinkling of skin
decreased libido
hair loss
queen annes sign
alopecia due to TSH loss
loss of sex hair
d/t loss of ACTH
cuases of ant pituitary failure
vindicated Vascular infection or infiltrative neoplastic disorders degenerative or deficiency states idiopathic congenital allergic or autoimmune trauma endocrine disorders
vascular causes of ant pit failure
pituitary apoplexy sheehans carotid aneurysms strokes SM
infectious causes of ant pit failure
syphilis TB abscess fungal parasite
infiltrative causes of ant pit failure
sarcoid langerhas cell histiocytosis wegners leukemia lymphoma hemochromatosis amyloid
neoplastic disorders which cause ant pit failure
adenoma mets menigioma optic glioma craniopharyngioma pineal dysgerminoma
congenital causes of ant pit failure
kallman syndrome-GNRH stays in nose
PROP 1 mutation
Dax-1 mutation
prader-willi
allergic or autoimmune causes of ant pit failure
lymphocytic hypophysitis
endocrine disorder causes of ant pit failure
hypothalamic or pit disease
MEN1
if 2 pit hormones are low and IGF-1 is low what can you assume
that GH is also low
8AM cortisol
should be >3ug/dl
ACTH sitmulation
cortisol should be <18ug/dl in 45min
what happens to ADH in hypopituitarism
low thyroixine and low coritsol -> decrease CO -> increased ADH
cortisol usually inhibits ADH as well and is missing
become hyponatremic, but hypotensive bc of low epi
Uosm in SIADH
150-200
how does hypothyroidism cuase hypotonic euvolemic hyponatremia
decreased CO and decreased ECV
psychogenic polydipsia Uosm
<100
idiopathic hyponatremia of elderly Uosm
<100
how does hypopituitarism cause hypoglycemia
loss of hormones which counter insulin:
Epi
cortisol
GH
if you replace cortisol and patient develops polyuria…
panhypopituitarism
did not realize pt had DI b/c GFR was too low d/t loss of cortisol
with replacement of cortisol GFR normalizes and DI becomes apparent
causes of polyuria
C-DRIPPED cortisol excess DI recovery from renal failure ions (hyper Ca, hypo K) Parkinsons PP enzyme- vasopressinase (autoimmune DI) Drugs
serum UA
excreted d/t ADH binding V1 Rs
so high serum UA -> low/absent ADH
desmopressin
resistant to vasopressinade
can cause serious depression and suicide