Adrenal Gland Disorders

Question 1

what is adrenal insufficiency

Answer 1

inadequate adrenocortical function

Question 2

causes of primary adrenal deficiency

Answer 2

Addisons disease
Congenital adrenal hyperplasia
Adrenal TB/malignancy

Question 3

causes of secondary adrenal insufficiency

Answer 3

Lack of ACTH stimulation
Iatrogenic (excess exogenous steroid)
Pituitary/hypothalmic disorders

Question 4

what is the most common cause of primary adrenal insufficiency

Answer 4

Addisons disease

Question 5

how much of the adrenal cortex must be destroyed to show symptoms in Addisons disease

Answer 5

90%

Question 6

what is Addisons disease

Answer 6

autoimmune destruction of the adrenal cortex

Question 7

what are some clinical features of Addisons

Answer 7

anorexia, weight loss 
fatigue/lethargy 
Dizziness and low BP 
Abdominal pain, vomiting, diarrhoea 
Skin pigmentation

Question 8

how do you diagnose adrenal insufficiency

Answer 8

Biochemistry (low Na, high K, hypoglycaemia)
Short SynACTHen test (give loads of ACTH and see if adrenals respond)
ACTH levels
Renin/aldosterone levels
Imaging

Question 9

why does ACTH rise so much in Addisons

Answer 9

because no cortisol is produced to have a negative feedback response

Question 10

how do you treat adrenal insufficiency

Answer 10

Hydrocortisone as cortisol replacement

Fludrocortisone as aldosterone replacement

Question 11

what is secondary adrenal insufficiency

Answer 11

adrenal insufficiency caused by a lack of CRH/ACTH

Question 12

what causes secondary adrenal insufficiency

Answer 12

pituitary/hypothalamic disease tumours

exogenous steroid use (Most common cause)

Question 13

how does exogenous steroid use cause secondary adrenal insufficiency

Answer 13

Exogenous steroid has negative feedback on CRH and ACTH stopping it from producing natural cortisol

Question 14

what are the clinical features of secondary adrenal insufficiency

Answer 14

similar to Addisons however:

• paler as no build up of ACTH
• Aldosterone production in tact (regulated by RAS)

Question 15

treatment for secondary adrenal insufficiency

Answer 15

Treat with hydrocortisone replacement

Question 16

What is Cushing’s syndrome

Answer 16

excess cortisol secretion

Question 17

clinical features of Cushing’s

Answer 17

common in women aged 20-40 
easy bruising 
facial plethora 
stria 
proximal myopathy 
osteoporosis 
hyperglycaemia 
increased appetite 
increased abdominal fat 
skin thinning 
buffalo hump 
benign inter cranial hypertension

Question 18

what are some ACTH dependent causes of Cushing’s syndrome

Answer 18

pituitary adenoma (Cushings disease)
Ectopic ACTH production from a tumour
Ectopic CRH production from a tumour

Question 19

what are some ACTH independent causes of Cushing’s syndrome

Answer 19

adrenal adenoma
adrenal carcinoma
nodule hyperplasia

Question 20

how to diagnose Cushing’s syndrome

Answer 20

establish theres a cortisol excess by:

overnight dexamethasone suppression test (giving high dose dexamethasone should suppress cortisol production)
24 hour free cortisol
late night salivary cortisol

low dose dexamethasone suppression test

Question 21

what is the screening test for cushings

Answer 21

low dose dexamethasone test can be done in an outpatient clinic

1mg of dexamethasone is given to see if it surpasses cortisol production

repeat to confirm

Question 22

what is the most common cause of cortisol excess

Answer 22

Iatrogenic Cushing’s syndrome from prolonged use of high dose steroid therapy

leads to chronic suppression of pituitary ACTH production and adrenal atrophy

Question 23

what are the negative implications of adrenal cortex atrophy

Answer 23

unable to produce steroids so:

unable to respond to stress (illness/surgery)
need extra doses of steroid when ill
cannot stop steroid replacement treatment suddenly - gradual withdraw needed

Question 24

What is primary aldosteronism

Answer 24

Too much aldosterone due to autonomous production independent of it’s regulators (angiotensin II/potassium)

Question 25

what causes primary aldosteronism

Answer 25

Adrenal adenoma (Conn's adenoma) Bilateral adrenal hyperplasia (most common cause) rarer causes - genetic mutation - unilateral hyperplasia

Question 26

what are the normal cardiovascular actions of aldosterone

Answer 26

altered endothelial function (increased pressor response) increased sympathetic outflow increased cardiac collagen cytokinesis and ROS synthesis sodium retention

Question 27

Clinical features of primary aldosteronism

Answer 27

significant hypertension hypokalaemia alkalosis

Question 28

how do you diagnose primary aldosterone

Answer 28

1. confirm aldosterone excess - measure plasma aldosterone and renin as a ration - if the ratio is raised then do saline suppression test (increasing blood volume should inhibit aldosterone release) 2. confirm subtype - adrenal CT for Aden,a - sometimes adrenal vein sampling can confirm if adenoma is the true source

Question 29

how do you manage primary aldosteronism

Answer 29

Surgically -unilateral laparoscopic adrenalectomy (only if adrenal adenoma) medically - used in adrenal hyperplasia - use mineralocorticoid receptor antagonists (spirolactone)