Adrenal Disorders

Question 1

What does the adrenal cortex produce?

Answer 1

1. Glucocorticoids (cortisol) - affect carbohydrate, lipid and protein metabolism
2. Mineralocorticoids (aldosterone) - control sodium and potassium levels
3. Androgens - sex hormones

Question 2

What is Cushing’s syndrome?

Answer 2

The clinical state produced by chronic exposure to high cortisol levels

Question 3

What are the clinical features of cushing’s syndrome?

Answer 3

Round plethoric face, acne, skin thinning, bruising, hirsutism, central obesity, buffalo hump, proximal muscle weakness, mood disturbances, hypokalemia

Question 4

What causes cushings syndrome?

Answer 4

Endogenous:
- ACTH dependent) - increased ACTH due to cushings disease (pituitary adenoma) or other cancer
- ACTH independent - adrenal adenoma, nodular hyperplasia
Exogenous:
- Steroid use

Question 5

What is the first line investigation of Cushing’s?

Answer 5

24 hour urinary free cortisol excretion AND
Overnight dexamethasone suppression test

If tumour is suspected, do CT/MRI to investigate

Question 6

What causes hypoadrenalism?

Answer 6

Primary - autoimmune (addisons), TB, HIV

Secondary - Prolonged exogenous steroids, pituitary lesions

Question 7

What is Addison’s disease?

Answer 7

Adrenal insufficiency due to autoimmune destruction of the adrenal gland

Question 8

What are the symptoms and signs of Addison’s disease?

Answer 8

Lean, TANNED, tired, tearful, dizzy, faints, mood disorders - very non-specific

Question 9

How can hypoaldrenalism be investigated?

Answer 9

Short synacthen test:

• Do baseline bloods for cortisol and acth
• Give 250 mcgrams synacthen IM (corticotrophic agent)
• Measure cortisol at 0, 30, 60 minutes

Those with hypoadrenalism will have only small rises in cortisol

Question 10

How can hypoaldrenalism be treated?

Answer 10

Glucocorticoid replacement (hydrocortisone, prednisolone, dexamethasone)

Mineralocorticoid replacement (fludrocortisone) - NB this isn’t necessary in secondary hypoadrenalism as the adrenal cortex is still intact)

Question 11

When should steroids be given?

Answer 11

Earlier in the day as they can cause insomnia

Question 12

What is an Addisonian crisis?

Answer 12

Shock, drowsiness, N&V, low BP, severe headache, hyperkalemia, hyponatremia, hypoglycaemia etc - precipitated by severe physical shock, infection, infarction or dehydration

Question 13

How should an Addisonian crisis be managed?

Answer 13

IV fluid bolus

IV hydrocortisone STAT

Question 14

What is metyrapone?

Answer 14

Treatment given in cushion’s syndrome that suppresses steroid biosynthesis

Question 15

Describe the system that leads to androgen and glucocorticoid production

Answer 15

1. Hypothalamus secretes corticotrophin-releasing factor
2. Pituitary secretes ACTH
3. Adrenal cortex produces androgens/glucocorticoids

This is a negative feedback system

Question 16

What are the symptoms of hyperaldosteronism?

Answer 16

Weakness, cramps, paraesthesia, polyruia, polydipsia, hypokalaemia

Question 17

What causes hyperaldosteronism

Answer 17

Primary - adnema (Conn’s syndrome), carcinoma

Secondary - renal artery stenosis, hepatic failure, hypertension (causes high renin from low renal perfusion)

Question 18

How does renin work?

Answer 18

Juxtaglomerular cells in the kidney secrete renin when there is low renal perfusion, in order to increase blood pressure.

Question 19

How is hyperaldosteronism treated?

Answer 19

Spironolactone usually