Endo 8 - Therapeutic Use of Adrenal Steroids

Question 1

Name the three parts of the adrenal cortex

Answer 1

Zona Glomerulosa
Zona Fasciculata
Zona Reticularis

Question 2

What steroid is produced in each zone?

Answer 2

Glomerulosa - aldosterone
Fasciculata - Cortisol
Reticularis - sex steroids

Question 3

Which hormone controls the production of adrenal sex steroids and cortisol?

Answer 3

ACTH

Question 4

Which hormone controls aldosterone production in adrenals?

Answer 4

Angiotensin II

Question 5

State the 4 triggers of aldosterone release

Answer 5

Hyperkalaemia
Hyponatraemia
Drop in renal blood flow
Beta 1 stimulation

Question 6

What is the principle action of aldosterone?

Answer 6

Increased sodium reabsorption

Increases potassium secretion

Question 7

Name 3 differences between glucocorticoid receptors and mineralcorticoid receptors?

Answer 7

GRs widely distributed
GRs selective for glucocorticoids, MRs non selective for both
GRs have low affinity for cortisol

Question 8

Describe how MRs are protected from cortisol stimulation

Answer 8

11-hydroxysteroid dehydrogenase-2 which converts cortisol to inactive cortisone

Question 9

Why do you get Hypokalaemia in Cushing’s syndrome?

Answer 9

So much cortisol that it overloads the 11HSD system so activates mineralcorticoid receptors

Question 10

Name 3 glucocorticoid drugs

Answer 10

Hydrocortisone
Prednisolone
Dexamethasone

Question 11

Which drug is the strongest glucocorticoid?

Answer 11

Hydrocortisone

Question 12

What is prednisolone mainly used for?

Answer 12

Immune suppression

Question 13

What is dexamethasone used for?

Answer 13

Anti oedema

Question 14

Name a mineralcorticoid - aldosterone analogue?

Answer 14

Fludrocortisone

Question 15

How are mineralcorticoids and glucocorticoids administered?

Answer 15

Orally

Question 16

Where are corticosteroids metabolised and excreted?

Answer 16

Metabolised in liver

excreted in bile and urine

Question 17

State 5 reasons for prescribing corticosteroid therapy>

Answer 17

Primary adrenocortical failure
Secondary adrenocortical failure
CAH
Iatrogenic adrenocortical failure
acute adrencortical failure

Question 18

What is the treatment for primary adrenocortical failure>

Answer 18

replace both cortisol and aldosterone so

hydrocortisone and fludrocortisone

Question 19

What is secondary adrenocortical failure?

Answer 19

Adrenals are working fine, but problem with pituitary e.g ACTH deficiency
Normal aldosterone production as ACTH does not control
So only cortisol needs to be replaced - hydrocortisone

Question 20

What is the treatment for acute adrenocortical failure (Addisonian Crisis)

Answer 20

IV Saline

High dose hydrocortisone

Question 21

What is the most common cause of CAH?

Answer 21

21-hydroxylase deficiency

Question 22

Describe the ACTH levels in CAH?

Answer 22

High ACTH as no cortisol being produced

High ACTH means increase in adrenal sex steroids

Question 23

What are the consequences of CAH in childhood?

Answer 23

virilisation and precocious puberty if partial deficiency

Question 24

How do you treat CAH?

Answer 24

Replace cortisol with hydrocortisone

Replace aldosterone with fludrocortisone

Question 25

How do you monitor CAH?

Answer 25

Measure 17hydroxyprogesterone levels

Question 26

When would you change the dose of hydrocortisone in CAH?

Answer 26

When stressed e.g. infection

Question 27

What is iatrogenic adrenocortical failure?

Answer 27

long term high dose glucocorticoid therapy can suppress HPA axis and thus suppress adrenal function