Chem path 6 - Adrenals Flashcards
What are wasted adrenal glands likely to be due to?
Addison’s disease or prolonged steroid use
What may hyperplastic adrenal glands be due to?
Cushing’s disease
Ectopic ACTH
Is cortisol more abundant or aldosterone?
CORTISOL (measured in nanomoles whereas aldosterone measured in picomoles)
Waterhouse-Friedrichsen syndrome
Adrenal failure due to bleeding in to the adrenals commonly caused by severe bacterial infection (neisseria meningitides)
Blood supply of adrenals
Many arteries but only 1 vein
Left adrenal: INTO THE RENAL VEIN
Right adrenal: INTO IVC
What is Schmidt’s syndrome?
Co-existence of primary hypothyroidism + Addison’s
What is another name for Schmidt’s syndrome?
Polyglandular autoimmune syndrome type II
What is the 1st line investigation for suspected Addison’s?
Short synACTHen test - if cortisol <550nM after 30 and 60 mins = Addison’s
Management of Addison’s
IV 0.9% Saline (1L/hr) + IV hydrocortisone
32yo with HTN + adrenal mass, what are the 3 differential diagnoses?
Phaeo
Conn’s
Cushing’s
Adrenaline vs noradrenaline
Adrenaline = adrenal catecholamine Norad= peripheral catecholamine
What is the test for phaeo?
Urinary catecholamines
Management of phaeo
MEDICAL EMERGENCY
1) Alpha blockade (phenoxybenzamine) –> reflex tachycardia –> step 2
2) beta blockade
3) surgery (high dose alpha and beta blockade in the days leading up to op)
What are the genetic links with phaeo?
Men2
VHL
NF1
VHL features
Phaeo
Renal call carcinoma
Renal cysts
Haemangioblastomas
NF1
Cafe au lait
Peripheral/spinal neurofibromas etc
Phaeo
MEN2 features
Phaeo
Parathyroid tumour
MTC
(Men 2b = marfanoid)
MEN 1 (3 Ps)
Pituitary
Parathyroid
Pancreatic
How do you treat Conn’s?
Aldosterone antagonists/potassium sparing diuretics: spironalactone/eplerenone/amiloride
What is pseudo-cushing’s syndrome?
Obestiy can change your metabolism of cortisol and produce a clinical picture that looks like Cushing’s (no mx required)
What is the commonest cause of Cushing’s syndrome?
Steroids
What are the tests for Cushing’s?
9am cortisol
Midnight cortisol (if this is LOW then definitiely NOT cushing’s)
LDDST
How is a LDDST preformed?
measure cortisol and ACTH at start, then administer 0.5mg dexamethasone every 6 hours for 48 hours then measure cortisol 9am.
If a pt fails to suppress cortisol after LDDST, what is the next step?
IPSS (INFERIOR PETROSAL SINUS SAMPLING)
