Chempath 15: Adrenal Disease

Question 1

What are the 3 zones of the adrenal cortex ?

Answer 1

Zona glomerulosa
Zona Fasciculata
Zona Reticularis

Question 2

In which zone of the adrenal cortex is aldosterone produced ?

Answer 2

Zona Glomerulosa

Question 3

In which zone of the adrenal cortex is cortisol produced ?

Answer 3

Zona fasciculata

Question 4

In which zone of the adrenal cortex are androgens such as DHEA produced ?

Answer 4

Zona reticularis

DHEA (dehydroepiandosterone) is a precursor to male and female sex hormones including oestrogen and testosterone

Question 5

Where is adrenaline produced ?

Answer 5

Adrenal Medulla

Question 6

List 2 potential causes of hyperplastic Adrenal glands ?

Answer 6

Cushing’s disease 
Ectopic ACTH (e.g lung tumour)

Question 7

Where does the Right adrenal gland drain into ?

Answer 7

Inferior vena cava (IVC)

Question 8

Where does the left adrenal gland drain into ?

Answer 8

Left renal vein

Question 9

What is schmidt’s syndrome ?

Answer 9

A syndrome of co-existing hypothyroidism and Addison’s disease due to autoantibodies against both the thyroid and the adrenals

Hyponatraemia + hyperkalaemia (mineralocorticoid deficiency)
Hypoglycaemia (glucocorticoid (cortisol) deficiency)
low T4 high TSH (Primary hypoparathyroidism)

Question 10

Which test is used to diagnose Addison’s disease ?

Answer 10

Short synACTHen test

Question 11

Explain how the short synACTHen test works and what results you would expect in Addison’s disease ?

Answer 11

1)- measure initial cortisol +ACTH
2)- Administer synthetic ACTH by IM injection
3)- check cortisol at 30 and 60 mins
In normal people cortisol should be able get to >550 nM

In Addison’s disease Cortisol does increase after synthetic ACTH and stays <10nM

Question 12

Which test is used to diagnose phaeochromocytoma ?

Answer 12

Urine catecholamines - high = phaeochromocytoma

Question 13

What is a phaeochromocytoma ?

Answer 13

An adrenal medullary tumour that secretes adrenaline causing hypertension, arrhythmias, sweating, impending sense of doom

Question 14

List 3 genetic conditions in which phaeochromocytoma is seen ?

Answer 14

MEN2
Von Hippel Lindau syndrome
Neurofibromatosis type 1

Question 15

List 3 features of MEN2a?

Answer 15

Parathyroid tumours
Medullary thyroid cancer
Phaeochromocytoma

Question 16

List 4 features of Von Hippel Lindau syndrome ?

Answer 16

Phaeochromocytoma
Renal cell carcinoma
Renal cysts
Retinal/CNS haemangioblastomas

Question 17

List up to 6 features of Neurofibromatosis type 1

Answer 17

Peripheral and spinal neurofibromas 
Cafe au lait spots
Axillary freckling 
Lisch nodules on iris 
Phaeochromocytoma 
Renal artery stenosis

Question 18

What is Conn’s syndrome ?

Answer 18

Primary hyperaldosteronism causing hypertension, hypokalaemia and inhibition of renin secretion

Question 19

Which test can be done to diagnose Conn’s syndrome ?

Answer 19

Serum aldosterone: renin levels

Conn’s: high Aldosterone:renin ratio

Question 20

How can you test for Cushing’s ?

Answer 20

9am cortisol
12pm midnight cortisol (if low then very strong negative predictive value that it is not Cushing’s)
Low dose dexamethasone suppression test ( if cortisol not suppressed then Cushing’s)

Question 21

Which tests can help differentiate Cushing’s syndrome from Cushing’s disease?

Answer 21

High dose Dexamethasone suppression test- pituitary tumour secreting ACTH shows some suppression in cortisol. Adrenal ACTH tumours are not suppressed.

Inter petrosal sinus sampling (IPSS)- sampling of the pituitary for an ACTH secreting tumour

Question 22

Why is IPSS preferred to High dose dexamethasone suppression test?

Answer 22

High dose dexamethasone test has a 20% false positive rate

Question 23

List 3 features of MEN2b ?

Answer 23

Phaeochromocytoma
Medullary thyroid cancer
G.I tract mucocutaenous neuromas