Adrenal Physiology and Disease

Question 1

Aldosterone is synthesised in what part of the adrenal cortex?

Answer 1

Zona glomerulosa

Question 2

Cortisol is synthesised in which part of the adrenal cortex?

Answer 2

Zona fasciculata

Question 3

Outline the hypothalamic-pituitary-adrenal (HPA) axis

Answer 3

The hypothalamus secretes CRH causing the pituitary to secrete ACTH stimulating the adrenal cortex to secrete cortisol

Question 4

How is aldosterone produced?

Answer 4

Renin produces angiotensin I which becomes angiotensin II which produces aldosterone

Question 5

Cortisol causes increased/decreased blood pressure

Answer 5

Increased

Question 6

What is the common name for primary adrenal insufficiency?

Answer 6

Addison’s disease

Question 7

What occurs in Addison’s disease?

Answer 7

Complete autoimmune destruction of the adrenal cortex

Question 8

Give some clinical features of Addison’s

Answer 8

Anorexia
Fatigue
Hypotension
Abdo pain
Pigmentation

Question 9

What are the relative sodium and potassium levels in Addison’s?

Answer 9

Sodium is low and potassium is high

Question 10

What occurs in a short synacthen test?

Answer 10

ACTH is injected and plasma cortisol is measured

Question 11

What drugs are used in Addison’s?

Answer 11

Hydrocortisone - replaces cortisol

Fludrocortisone - replaces aldosterone

Question 12

What is the commonest cause of secondary adrenal insufficiency?

Answer 12

Exogenous steroid use

Question 13

What occurs in Cushing’s syndrome?

Answer 13

There is excess cortisol secretion

Question 14

Give some features of Cushing’s

Answer 14

Easy bruising
Striae
Proximal myopathy

Question 15

What is the commonest cause of primary Cushing’s?

Answer 15

Pituitary adenoma

Question 16

What test is done to diagnose Cushing’s?

Answer 16

Overnight dexamethasone suppression test

Question 17

What is the commonest cause of iatrogenic Cushing’s?

Answer 17

Prolonged high dose steroid usage

Question 18

What is primary aldosteronism?

Answer 18

Autonomous production of aldosterone independent of its regulators

Question 19

Primary aldosteronism due to an adrenal adenoma is known as?

Answer 19

Conn’s syndrome

Question 20

Primary aldosteronism is the commonest cause of secondary hypertension. True/false?

Answer 20

True

Question 21

How is aldosterone excess confirmed?

Answer 21

Aldosterone and renin are measured before saline suppression test occurs

Question 22

How is Conn’s syndrome confirmed?

Answer 22

Adrenal CT

Question 23

How is Conn’s syndrome managed?

Answer 23

Laproscopic adrenalectomy

Spironolactone

Question 24

What is another important cause of primary aldosteronism?

Answer 24

Bilateral adrenal hyperplasia

Question 25

Congenital adrenal hyperplasia (CAH) is most commonly caused by what?

Answer 25

21-alpha hydroxylase deficiency

Question 26

In CAH there is increased production of which hormone?

Answer 26

Testosterone

Question 27

How does CAH commonly present?

Answer 27

Males - adrenal insufficiency | Females - genital ambiguity

Question 28

What are the main principles in treating CAH?

Answer 28

Glucocorticoid replacement | Surgical correction

Question 29

A tumour of the adrenal medulla is known as?

Answer 29

Phaeochromocytoma

Question 30

What is the classical triad seen in phaeochromocytoma?

Answer 30

Hypertension Headache Sweating

Question 31

Give some signs of phaeochromocytoma

Answer 31

Hypertension Pallor Postural hypotension

Question 32

90% of phaeochromocytomas become malignant. True/false?

Answer 32

False - 10% (10% tumour!)

Question 33

How is phaeochromocytoma investigated?

Answer 33

Urine for catecholamines | MRI whole body

Question 34

What drugs are used to treat phaeochromocytoma?

Answer 34

``` Alpha blocker (phenoxybenzamine) Beta blocker (propranolol) ```

Question 35

Laproscopic surgery can be done in phaeochromocytoma. True/false?

Answer 35

True