Endocrinology 2 - Cushing's Syndrome

Question 1

Give all 12-14 features of Cushing’s syndrome

Answer 1

round moon face
central obesity 
abdominal striae 
buffalo hump on back 
proximal limb muscle wasting 
hypertension 
cardiac hypertrophy
hyperglycaemia
type 2 diabetes
depression 
insomnia 
osteoporosis 
easy bruising
poor healing/immunity

Question 2

4 causes of Cushing’s syndrome

Answer 2

iatrogenic - taking steroids
pituitary adenoma (‘disease’)
adrenal adenoma
ectopic ACTH

Question 3

describe low vs high dose dexamethasone suppression test

Answer 3

1mg vs 8mg

low dose identifies whether Cushing’s syndrome is present, high dose identifies the cause

Question 4

give the different outcomes with low and high dose dexa suppression tests (pit adenoma, adrenal adenoma, ectopic ACTH)

Answer 4

low dose - all fail to have cortisol levels suppressed

high dose
PitAdenoma (both C + ACTH suppressed)
AdrAdenoma (only ACTH suppressed)
ectopic (neither suppressed)

Question 5

what is the usual cause of ectopic ACTH?

Answer 5

small cell lung cancer

Question 6

suggest a panel of investigations for the different causes of Cushing’s syndrome

Answer 6

FBC, U+Es
MRI for pituitary
CT abdo for adrenal
CT chest for ectopic

Question 7

how do you treat Cushing’s syndrome?

Answer 7

remove the cause

either stop the drugs or remove the secretor

if can’t remove the direct trigger, can remove both adrenals and replace

Question 8

what surgical approach is used for pituitary surgery

Answer 8

trans-sphenoidal