Adrenal glands Flashcards
Cushing most frequent type
Iatrogen by steroid medication
2 main types of Cushing
ACTH dependant :
- ACTH producing hypophysis adenoma (m. Cushing, 70%)
- Ectopic ACTH production
ACTH independant
- adrenocortical adenoma
- adrenocortical carcinoma
Cushing Work Up
Dexamethasone stress test (1mg Dexamethasone midnight, Cortisol serum at 8am)
if < 140nm/l = no cushing
If above Head MRI
Cushing treatment
Neurosurgical
Adrenalectomy only als ultima ratio and for adrenal origin
Cushing post op
The healthy side is in hypo.
Substitute with cortisol post operatively.
Conn syndrome
Primary hyperaldosteronism
Conn Syndrome (clinic)
High blood pressure because of hypervolemia
Hypokaliemia and Metabolic alcalosis
Conn Syndrome mechanism
Aldosterone acts mainly on kidney Stimulation of ENaC and ROMK channels increases sodium resorption increases potassium excretion chloride follows sodium Also acts on apical Proton ATPase and causes secretion that acidifies urine and alkalises extracellular fluid
Why renin decrease ?
Elevated blood pressure
- > increased glomerular filtration rate
- > drop in renin (granular cells of the juxtaglomerular apparatus)
Conn main types
idiopathic bilateral 72%
unilateral adenome 28%
adrenal carcinoma seldom
Diagnosis
serum aldosteron concentration (high)
plasma renin activity (low)
Captopril test
Sodium loading test
Fludrocortisone suppression test
CT
Noriodocholesterol scintigraphy
Sampling of venous adrenal veins (gold standard)
Captopril suppression test
Captpril (ACE inhibitor) supresses renin angiotension aldosterone system
Normally, aldosterone should drop and therefore ARR should be lower. In Conn, stays high.
Differential of Conn
Liddle Syndrome (ENAC Mutation) Licorice, pastis (glycyrrhizin)
What to do by IHA
Medication, no surgery
Localised Conn Adenoma
generally less than 2cm
lap adrenalectomy
can go out of BP meds in 60% of cases
