Adrenal Flashcards
What’s function of aldosterone?
NA retention, K excretion
What’s hormonal workup for adrenal mass?
Urine metanephrine/VMA/catecholamine, urinary hydroxycorticosteroids, serum K w plasma renin/aldosterone, look for primaries
What are suggestive of benign adrenal mass?
<4 cm, smooth, <10 HU, >60% washout on 15 minute delay phase, simple cyst, myelolipoma
What is the cortisol regulatory axis?
CRH (Hypothalamus) -> ↑ACTH (ant pituitary) -> ↑Cortisol -> ↓CRH
What mneumonic for congenital adrenal hyperplasia?
C A T
2 1 _ up
1 7 up _
1 1 up up
A: aldosterone
T: sex hormone
How do you diagnose hyperaldosteronism?
Salt load suppression test (urine aldosterone remains high)
Plasma aldosterone:renin >20 (AR)
How do you treat hyperaldosteronism?
Adenoma: adrenalectomy
Hyperplasia: spironolactone (suppresses aldosterone), CCB (nifedipine), K replace
Refractory: Bilateral adrenalectomy (give fludrocortisone postop)
How do you workup low cortisol level?
Cosyntropin test (ACTH) to check for adrenal insufficiency
How do you workup high cortisol level?
24H urine cortisol test (verify hypercortisolism) and ACTH
IF ACTH low: patient has a cortisol secreting lesion (adrenal hyperplasia/adenoma)
IF ACTH high, perform high dose dexamethasone suppression test
- If urine cortisol suppressed: pituitary adenoma
- If urine cortisol is not suppressed: ectopic ACTH
How do you treat adrenal hyperplasia?
Metryrapone (11B hydroxylase inhibitor -> ↓cortisol synthesis), aminoglutethimide (inhibit steroid production), bilateral adrenalectomy if refractory
What’s chemo agent for adrenal cancer? When is it used?
Mitotane. High grade (Ki67>10, >20 mitosis/50HPF, intraoperative tumor spillage, capsular invasion, recurrent/metastatic disease
What’s the rate limiting step of catecholamine production?
Tyrosine hydroxylase
What converts norepinephrine to epinephrine?
PNMT
What is a notable point of extraadrenal neural crest tissue?
Organ of Zuckerkandl at aortic bifuration
Which side if pheo more common in?
Right
How do you test for pheo?
Screening with plasma metanephrine. Confirm with 24H urine metanephrine. Can also do urine VMA, MIBG scan, clonidine suppression test (clonidine will not suppress catecholamine secretion)
What are critical periop element of pheo?
IVF, alpha-blocker (phenoxybenzamine, prazosin), beta-block once tachycardic or getting arrhythmia, metyrosine (tyrosine hydroxylase inhibitor)
Have nitroprusside, neosynephrine, antiarrhythmic agents available
What hormones does posterior pituitary secrete?
ADH, oxytocin
What’s blood supply for anterior pituitary?
portal venous supple from posterior pituitary
What’s indication for treating prolactinoma? What’s the treatment?
Symptomatic or macroadenoma >10 mm.
Bromocriptine (safe in pregnancy), cabergoline
If failure/hemorrhage/visual loss/desiring pregnancy/CSF leak:
Transsphenoidal resection
What’s Bromocriptine/Cabergoline’s mechanism?
Dopamine agonist
What’s Conn’s? What’s Addison’s?”
Addison: hypoaldosterone
Conn: Hyperaldosterone
