CABS- Endocrine HTN Flashcards
3 main adrenal gland causes of HTN
pheochromocytoma
primary aldosteronism (Conn’s)
cushing syndrome
thyroid causes of HTN
hyperthyroidism
pituitary causes of HTN
acromegaly
cushing disease
tumor that arises from Chromaffin cells of adrenal medulla
pheochromocytoma
pt presents with HA, sweating, palpitations, HTN, anxiety, feeling of impending death
pheochromocytoma
first 2 steps to diagnose pheochromocytoma
urine metanephrine
plasma metanephrine
MRI w/ I-MIBG +/or Ga-DOTATE scan to diagnose what (adrenal or extradrenal)
pheochromocytoma
first line to treat pheochromocytoma (alpha blocker)
phenoxybenzamine
2nd line to treat pheochromocytoma
metoprolol
how to definitively treat pheochromocytoma
surgery
end product of epi and NE
VMA
epi into _____ by MAO enzyme
metanephrine
NE into ___ by MAO enzyme
normetanephrine
why epinephrine-secreting pheochromocytomas are almost exclusively localized to adrenal medulla?
b/c adrenal medulla is only tissue to normally produce large amounts of epi due to presence of PNMT
crucial enzyme for turning norepinephrine into epinephrine
PNMT
not used as initial antihypertensive agent in pheochromocytoma b/c it can cause intraoperative HTN
Labetolol
more of a beta blocker than alpha blocker
Labetolol
____ can increase blood glucose by inhibiting insulin secretion via alpha2 agonism in beta cells
catecholamines
too much cortisol in Cushing saturates ______ which then allows it to bind and create apparent mineralocorticoid excess (causing hypokalemia and hypernatremia)
11beta-HSD2
normal plasma ____ at 8AM is 5-23 microgram/mL
cortisol
increase in ACTH and cortisol and responds to dexamethasone
Cushing Disease (ACTH-producing pituitary adenoma)
increase in CRH, ACTH, and cortisol
pseudo-Cushing (depression/anxiety)
increase in cortisol and decrease in ACTH; has little effect from dexamethasone
adrenal tumor
increase in ACTH and cortisol; doesn’t respond to dexamethasone
ectopic ACTH/CRH
urine free cortisol>3x above normal
cushing
midnight plasma cortisol>7.5
cushing
overnight high dose dexamethasone; cortisol at 8 AM >1.8
cushing syndrome
synthetic steroid that reduces cortisol levels by binding to same receptor as cortisol and decreases amount of ACTH released by pituitary gland
dexamethasone
______ works at high doses to suppress ACTH producing pituitary adenoma
dexamethasone
stress will ______ secretion of CRH from cell to stimulate ACTH and then cortisol
increase
normal or increased ACTH when measured (what differentials)
Cushing disease (ACTH-producing pituitary adenoma)
pseudo-Cushing
ectopic ACTH/CRH
decreased ACTH when measured (what differentials)
adrenal tumor
iatrogenic cushing
CRH and high dose DST +
Cushing Disease
CRH and high dose DST -
Ectopic ACTH/CRH
HTN + hypokalemia + metabolic alkalosis
Primary Aldosteronism (Conn’s)
to measure and diagnose Conn’s
increased PAC (aldosterone)
decreased PRA (renin)
to measure and diagnose secondary hyperaldosteronism
elevated PAC and PRA
confirmatory test for primary aldosteronism (Conn’s)
oral salt loading (NaCl); increased NaCl, decreased renin, increased aldosterone
24 hour urinary aldosterone excretion >12micrograms
Conn’s
vitamin deficiency in pt with pheochromocytoma
vitamin C (dopamine into NE; tryptophan into serotonin)
in MEN I, the most common secretory product of pancreatic and duodenal endocrine lesions
gastrin
blocks alpha1 in VSMC
blocks beta1 in juxtaglomerular cells (inhibits renin)
blocks beta1 in SA node
Labetolol
