Adrenal

Question 1

What are the anatomical layers of the adrenal cortex and associated hormone excreted?

Answer 1

Zona glomerulosa - mineracorticoids (aldosterone)
Zona fasiculata - glucocorticoids (cortisol)
Zona reticularis- androgen

Question 2

What are the hormones excreted by the adrenal medulla?

Answer 2

Adrenaline
Noradrenaline
Dopamine

Question 3

What is Cushing’s syndrome?

Answer 3

Excess circulating glucocorticoids

Question 4

List clinical features of Cushing syndrome

Answer 4

Obesity
Moon face
Plethora
Thin skin
Hirsuitism
Menstrual irregularity
Easy bruising
Proximal weakness (wasting of proximal thigh muscles)
Osteopenia/fracture
Nephrolithiasis

Question 5

List the potential causes of Cushing syndrome for the subset categories

1) ACTH dependent
2) ACTH independent

Answer 5

1)
a) Pituitary adenoma
b) Ectopic ACTH

2)
a) Adrenal adenoma
b) Adrenal carcinoma
c) Bilateral adrenal hyperplasia

Question 6

Sources of ectopic ACTH

Answer 6

small cell lung cancer
medullary thyroid cancer
carcinoid
Pancreatic cell islet tutor

Question 7

Biochemical tests for Cushing’s syndrome

Answer 7

Screening test:
-low dose overnight dexamethasone suppression test
-urinary free cortisol
Confirmatory test
-48 hour low dose dexamethasone suppression test
Localisation test:
-plasma ACTH
-48 hour high dose dexamethasone suppression test

Question 8

MEN1
hint: 3”P”

Answer 8

3Ps:
Parathyroid hyperplasia
Pancreatic endocrine tumor
Pituitary adenoma

Question 9

MEN2A
hint: 2P1M

Answer 9

2P1M:
Medullary thyroid cancer
Phaechromocytoma
Parathyroidhyperplasia

Question 10

MEN2B
hint: 3M1P

Answer 10

Phaechromocytoma
Medullary thyroid cancer
Mucocutaneous neuroma
Marfanoid habitus

Question 11

Familial syndromes for Phaechromocytoma

Answer 11

MEN2
NF1
VHL syndrome

Question 12

Arterial supply of adrenal glands

Answer 12

Direct branch of aorta
Superior adrenal artery from inferior phrenic artery
Inferior adrenal artery from renal artery

Question 13

Venous supply of adrenal

Answer 13

right adrenal to IVC
left adrenal to left renal vein

Question 14

Where are the adrenal glands situated

Answer 14

Right : superior aspect of kidney
Left: medial aspect of kidney

Question 15

What are the biochemical tests for primary hyperaldosteronism?

Answer 15

Screening test:
RFT: hyperNa, hypoK
BG: hypokalemic alkalosis
Spot plasma aldosteronone to renin ratio
Confirmatory tests: Sodium loading test
Localization test: Contrast CT +/- Adrenal venous sampling

Question 16

What are the biochemical tests for phaechromocytoma?

Answer 16

24 hour urine catecholamine
24 hour urine metanephrine
Plasma free metanephrine

Question 17

What is Addison’s disease?

Answer 17

Primary adrenal insufficiency, with failure to secrete glucocorticoids and mineralcorticoids

Question 18

Biochemical tests to confirm Addison;s disease?

Answer 18

Short synacthen test (ACTH)

Question 19

Phenoxybenzamine, why used for alpha blockade?

Answer 19

• non-selective
• alpha 1 and 2
• irreversible

Question 20

What is the formula for lateralization index?

Answer 20

[aldosterone] / [cortisol] of dominant AV

– – —————————————————–

[aldosterone]/[cortisol] non-dominant AV

Question 21

How to calculate the selectivity index?

Answer 21

[cortisol] of adrenal vein / [cortisol] of IVC

Question 22

What does the selectivity index indicate?

Answer 22

Whether the adrenal vein was successfully cannulate, requires SI of ≥3

Question 23

Spot ARR for Conn’s syndrome

Answer 23

≥ 750pmol/L per ng/ml/hr

Question 24

Possible confirmatory tests for Conn’s syndrome

Answer 24

• Oral salt loading test
• Saline infusion test
• Fludrocortisone suppression test
• Captopril challenge test

Question 25

What is the effect of aldosterone?

Answer 25

Increase open sodium channels in cortical collecting tubules → increase sodium and water retention