Adrenal Flashcards
Classically, CAH results from a mutation in which enzyme?
CYP21A2
CAH presents how in infants?
Virilisation of females and precocious puberty in males
Classical symptoms for Cushing’s Disease include (8)
1) Acne
2) Cushingoid face
3) Hirsutism
4) Abdominal striae
5) Osteoporosis
6) Hypertension
7) Impaired glucose tolerance
8) Erectile Dysfunction
The most common cause of Cushing’s Disease is….
Tumour of the corticotroph cells in anterior pituitary (70% of Cushing’s)
The vast majority of tumours in Cushing’s are micro/ macro-adenomas?
Micro-adenomas
Causes of ACTH-independent Cushing’s Syndrome include (2)
1) Adrenal adenoma / carcinoma
2) Bilateral macronodular adrenal hyperplasia
What’s the formal diagnostic test for Cushing’s?
Low-dose dexamethasone suppression test
If ACTH is low in a dexamethasone suppression test, what is the likely cause of the Cushing’s Syndrome?
Likely adrenal origin (as the body has lowered ACTH due to excess dexamethasone which resembles cortisol)
If an ACTH is raised in a dexamethasone suppression test, what origins need to be considered?
Pituitary (CD) & ectopic ACTH production - the body has not responded to the test at all
Which test can be used to differentiate ectopic from pituitary Cushing’s? How does it work?
High dose - it should suppress the pituitary somewhat but will have no effect on the ectopic production
A rise in cortisol & ACTH on a CRH test indicates which source for Cushing’s?
Pituitary (an ectopic source wouldn’t be stimulated by CRH test as it isn’t on this axis)
Cushing’s Disease leads to excessive androgens, true or false?
True
How does Cushing’s lead to hypertension?
There are excessive mineralocorticoids (e.g. aldosterone)
What’s the 1st line treatment in Cushing’s Disease?
Hypophysectomy and radiotherapy if recurrence
Medical treatments for Cushing’s Disease include (2)
1) Ketoconazole (hepatotoxic)
2) Somatostatin analogues
If Cushing’s is pituitary in origin, a low dose test will have what effect on ACTH?
None recognisable
In a high-dose dexamethasone test, what effect will there be on ACTH production in pituitary Cushing’s?
ACTH will be reduced
If ACTH production is not altered by high or low dose suppression testing, what is the likely source?
Ectopic
What effect does high-dose dexamethasone have on adrenal-origin ACTH?
None (c.f. pituitary which is suppressed)
Chronic Adrenal Insufficiency is also known as
Addison’s Disease
Acute-hypofunction of the adrenal gland due to ischaemia is termed
Waterhouse-Friderichsen Syndrome
Adenocortical carcinoma is rare and likely to be non-functional, T/F?
False - they are rare but are usually functional
Primary Hyperaldosteronism is termed
Conn’s Syndrome
Spironolactone bodies is a codeword for which condition?
Primary hyperaldosteronism
Pigmentation changes is characteristic of which adrenal condition?
Addison’s Disease (ACTH contains MSH code)
Addison’s Disease tends to only present when which % of gland is destroyed?
> 90%
The neuroendocrine chromaffin cells secrete what?
Catecholamines (such as adrenaline)
Phaeochromocytoma is a tumour which occurs where in the adrenal gland & secretes what?
Adrenal medulla & secretes catecholamines
The 3 most common causes of Addison’s (3)
1) Autoimmune adrenalitis
2) Infections
3) Metastatic malignancy
Phaeochromocytoma is often referred to as the 10% tumour - what does this mean? (5)
1) 10% are extra-adrenal
2) 10% are bilateral
3) 10% are malignant
4) 10% are NOT associated with hypertension
5) 25% familial (because why not)
Phaeochromocytoma is especially associated with which genetic condition?
MEN2A (RET oncogene mutation)
The 3 distinct zones of the adrenal gland are:
1) Zona glomerulosa
2) Zona fasciculata
3) Zona reticularis
Name the areas of the adrenal gland & what they secrete (6)
1) Zona glomerulosa -> mineralocorticoids (e.g. aldosterone)
2) Zona fasciculata -> Glucorticoids (e.g. cortisol)
3) Zona reticularis -> Sex steroids + glucorticoids.
4) Medulla = adrenaline
“Go, Find Rex, Make Good Sex, it’s Magic”
Aldosterone is regulated by which system?
Renin-Angiotensin (in response to low BP)
