PBL 4

Question 1

How doe she shape of the right adrenal gland differ form the left?

Answer 1

Right: pyramidal in shape
Left: semi-lunar in shape

Question 2

what separates the adrenal gland from the kidneys?

Answer 2

perirenal fat

Question 3

what lies anterior and posterior to the right adrenal gland?

Answer 3

Anterior: IVC, Right lobe fo liver
Posterior: Right crus of diaphragm

Question 4

what lies anterior and posterior to the left adrenal gland?

Answer 4

Anterior: Stomach, pancreas, spleen
Posterior: left crus of diaphragm

Question 5

where does the superior adrenal artery arise from?

Answer 5

inferior phrenic artery

Question 6

where does the middle adrenal artery arise from?

Answer 6

form the abdominal aorta

Question 7

where does the inferior adrenal artery arise from?

Answer 7

from the renal arteries

Question 8

list the tests used to diagnose adrenal insufficiency and what biochemistry signs will also be seen

Answer 8

Biochemistry: High Na, Low K – lack of aldosterone
SHORT SYNACTHEN TEST: Measure plasma cortisol before and 30 minutes after iv ACTH injection (IF AA = low cortisol)
ACTH levels - SHOULD BE HIGH if +ve as adrenal cortex trying to compensate
High renin and low aldosterone levels
Presence of Adrenal autoantibodies – against 21- hydroxylase

Question 9

what is the difference between primary and secondary adrenal insufficiency?

Answer 9

In primary adrenall insufficiency, glucocorticoid and mineralocorticoid properties are lost

In secondary adrenal insufficiency, mineralocorticoid function is preserved

Question 10

Outline investigations used to investigate possible cortisol excess

Answer 10

step 1: establish cortisol excess by giving exogenous steroids to suppress ACTH and cortisol production

step 2: measure ACTH, if undetectable = adrenal tumour

if normal/high = CRH stimulation test: if no change in ACTH = ectopic ACTH in lung, if exaggerated rise = pituitary adenoma

Question 11

how can iatrogenic and endogenous cortisol excess be distinguished biochemically?

Answer 11

In those with iatrogenic cortisol excess, their ACTH production will be suppressed and there will be adrenal atrophy

Question 12

describe the management of adrenal insufficiency and what patients must be educated about?

Answer 12

Hydrocortisone as cortisol replacement
Fludrocortisone as aldosterone replacement

Need education:
‘sick day rules’ – double dosage
Cannot stop steroids suddenly
Need to wear identification