Adrenal nodules
What layer of the adrenal cortex is responsible for corticosteroid synthesis?
Zona fasciculata
What unique adverse effect can dopamine agonists (Cabergoline, Bromocriptine) cause?
Impulse control issues, gambling, hypersexuality
What is the size difference between macroadenoma and microadenoma?
microadenoma < 1 cm
What layer of the adrenal cortex is responsible for production of mineralocorticoids?
Zona Glomerulosa
What region of the adrenal is responsible for production of epinephrine and norepinephrine?
A non-contrast CT scan of the adrenal glands shows a left sided 2cm adrenal nodule. Below what Hounsfield unit (HU) value would be suggestive of a lipid rich benign adenoma?
Less than 10 HU
What is the initial lab test to check for acromegaly?
IGF-1
What is the most common class of medications that cause hyperprolactinemia?
antipsychotics
True or false: The majority of cases of primary hyperaldosteronism do not present with hypokalemia
TRUE
What class of medications do you want to start prior to surgery for a Pheochromocytoma?
Alpha Adrenergic Blockers - Phenoxybenzamine / Prazosin
A 1.8cm adrenal adenoma (4HU) found incidentally on a non-enhanced CT scan of the abdomen. Hormonal evaluation was unremarkable. When would you repeat imaging and hormonal testing?
1) No repeat imaging needed
2) No strong evidence to support repeat biochemical testing- unless there is suspicion/clinical evidence of hormonal excess.
What pituitary hormone is critical to sustaining life especially in severe illness?
ACTH
What is the confirmatory test for acromegaly?
2 hour OGTT with GH measurements
Three screening tests for hypercortisolism:
24-hr urine free cortisol
Low dose (1mg) overnight Dexamethasone Suppression
Late Night Salivary Cortisol (x2)
Familial syndromes associated with Pheochromocytomas?
1. MEN2
2. VHL
3. NF1
When would you consider biopsy of an adrenal nodule?
Can consider if there is concern for metastatic disease to the adrenal gland
What syndrome is the patient at risk for after bilateral adrenalectomy for Cushing's?
Nelson Syndrome
What is an indication for transsphenoidal resection of non-functioning macroadenoma?
presence of abnormalities of VF or vision or signs of tumor compression of optic chiasm
The most common cause of primary hyperaldosteronism?
Bilateral Idiopathic Hyperaldosteronism
Which of these medications can cause false positive catecholamine level?
A. Alcohol
B. TCAs
C. Cocaine
All of them!
Screening for hormonal excess, abnormal values are as follows:
1) 1mg dexamethasone suppression test
2) Aldosterone / renin
3) Plasma/Urinary fractionated urinary metanephrines
Nonfunctional: ≤1.8 μg/dL
1) Possibly functional: 1.9-5 μg/dL
Autonomous hypercortisolism: >5.0 μg/dL
2) Aldosterone >20, ARR >20-30, low renin
3) Urinary/plasma metanephrines Greater than 2- to 4-fold higher than the upper limit of the reference range
What are the 3 stages, in order, of the triphasic response?
Diabetes insipidus, SIADH, Diabetes insipidus
What is the gold standard test to differentiate pituitary from non-pituitary ACTH-dependant Cushing syndrome?
When would you not need to proceed with confirmatory testing for hyperaldosteronism (example: Saline suppression testing)
No need if aldo >15 with low renin AND spontaneous hypokalemia
No need if aldo >20
Name of the cell pheochromocytoma develop from in the adrenal gland?
Chromaffin cells