Endo - Adrenal Disorders 1

Question 1

What are steroids derived from?

Answer 1

Cholesterol

Question 2

What does the adrenal cortex produce?

Answer 2

Corticosteroids

Question 3

What does the zone glomerulosa produce?

Answer 3

Mineralocorticoids

Question 4

What does the zona fasciculata produce?

Answer 4

Glucocorticoids

Question 5

What does the zona reticularis produce?

Answer 5

Sex steroids

Question 6

What does angiotensin 2 activate?

Answer 6

Side chain cleavage
3-Hydroxysteroid dehydrogenase
21 hydroxylase
11 hydroxylase
18 hydroxylase

Question 7

What does angiotensin 2 cause?

Answer 7

Aldosterone production

Question 8

How does aldosterone act?

Answer 8

Increases Na reabsorption and K excretion therefore controls blood pressure

Question 9

What does ACTH activate?

Answer 9

Side chain cleavage
3 hydroxysteroid dehydrogenase
17 hydroxylase
21 hydroxylase
11 hydroxylase

Question 10

What does ACTH cause?

Answer 10

Cortisol production

Question 11

Describe the pattern of cortisol secretion?

Answer 11

Diurnal - peaks at around 8:30 in the morning and is lowest around midnight/1am

Question 12

Describe the pathway from cholesterol to aldosterone

Answer 12

Cholsterol
Progesterone
11-deoxycorticosterone
corticosterone
aldosterone

Question 13

Describe the pathway of cholesterol to cortisol

Answer 13

Cholesterol 
Progesterone
17- hydoxyprogesterone
11-deoxycortisol
cortisol

Question 14

Describe the pathway of cholesterol to oestrogen

Answer 14

Cholesterol
Progesterone
17-hydroxyprogesterone
Sex steroids
Androgens
Oestrogen

Question 15

What is Addison’s disease?

Answer 15

Primary adrenal failure

Question 16

What is the commonest cause of Addison’s in the UK?

Answer 16

Autoimmune

Question 17

What is the commonest cause of Addison’s worldwide?

Answer 17

TB bacteria destroying the adrenal gland

Question 18

Why does Addison’s cause tanning?

Answer 18

We get an increase in ACTH due to negative feedback which is a product of POMC breakdown, along with MSH to increase pigmentation

Question 19

What does POMC break down into?

Answer 19

MSH, ACTH, endorphins, enkephalins, other peptides

Question 20

Where is POMC synthesised?

Answer 20

In the pituitary

Question 21

What are the signs of Addison’s?

Answer 21

Skin pigmentation
Autoimmune vitiligo 
Darkening of hair
Loss of weight 
Muscular weakness
Hypotension

Question 22

What are the 3 main causes of adrenocortical failure?

Answer 22

TB Addisons
Autoimmune Addisons
Congenital adrenal hyperplasia

Question 23

What are the consequences of adrenocortical failure?

Answer 23

Hypotnesion
Loss of salt in urine (hyponatremia)
Hyperkalemia
Hypoglycaemia (glucocorticoid deficiency)
Tanning
Eventual death due to severe hypotension

Question 24

What is the normal range for cortisol?

Answer 24

270-290nM

Question 25

How do we test for Addison's

Answer 25

Low 9am cortisol High ACTH No response after injecting 250µg synACTHen

Question 26

Why do we not give aldosterone for treatment of adrenal failure?

Answer 26

Half life too short for daily administration

Question 27

What do we use to treat adrenal failure?

Answer 27

Fludrocortisone 50-100mcg/daily

Question 28

Why do we use fludrocortisone?

Answer 28

Fluorine doesn't occur naturally in steroids therefore slows down metabolism and has much longer lasting effects (18h)

Question 29

Why do we not give oral hydrocortisone?

Answer 29

It ca be given but has too short a half life to be given once daily and can be harmful if given in too high a frequency therefore we opt for alternatives in replacing cortisol

Question 30

What is another name for 1,2-dehydrocortisone?

Answer 30

Prednisolone

Question 31

What dose of prednisolone can we give?

Answer 31

1mg, 2,5mg, 5mg once daily

Question 32

Why is prednisolone absorption slowed?

Answer 32

Not enteric coated

Question 33

Instead of prednisolone, what can we give alongside fludrocortisone?

Answer 33

We can give hydrocortisone 3 times daily (10, 5, 2.5 mg) to replicate the diurnal pattern of cortisol

Question 34

What is congenital adrenal hyperplasia?

Answer 34

Missing enzyme

Question 35

What is the most common enzyme missing?

Answer 35

21-hydroxylase

Question 36

What do we have in complete 21-h deficiency?

Answer 36

Cortisol and aldosterone deficient | Excess sex steroids (mainly testosterone)

Question 37

What is the survival rate for complete 21-h deficiency

Answer 37

Less than 24 hours unless given IV saline - as a neonate you are no longer dependent on placenta therefore have an Addisonian salt losing crisis

Question 38

What may we see in girls with complete 21-h deficiency?

Answer 38

Ambiguous genitalia (virilisation), prompting us to give hydrocortisone - we don't notice in boys

Question 39

What do we have in partial 21-h deficiency?

Answer 39

Still deficient in cortisol and aldosterone but there is enough to get by Still excess sex steroids and testosterone

Question 40

What is the presentation like in partial 21-h deficiency?

Answer 40

Presentation is much later, with hirsutism in girls and precocious puberty in boys

Question 41

What do we see in 11-h deficiency?

Answer 41

We should lose aldosterone and cortisol but 11-deoxycorticosteorne behaves just like aldosterone: No cortisol or aldosterone Excess 11-deoxycorticosterone, sex steroids and testosterone

Question 42

What is the presentation of 11-h deficiency?

Answer 42

Virilisation, hypertension and hypokalaemia

Question 43

What do we see in 17-h deficiency?

Answer 43

Deificient in cortisol and sex steroids | Excess 11-deoxycorticosterone and aldosterone

Question 44

What is the presentation of 17-h deficiency?

Answer 44

``` Hypertension Hypokalemia Sex steroid deficiency No puberty (you look like a child) Glucocorticoid deficiency (low glucose) ```