Hypoadrenal disorders

Question 1

What is the precursor of all adrenal steroids?

Answer 1

Cholesterol

Question 2

What is the most common cause of adrenocortical failure and how does it differ in developed and developing world?

Answer 2

Born with normal adrenal glands but they were destroyed:
Developing - TB
Developed - autoimmune

Question 3

What is a less common cause of adrenocortical failure?

Answer 3

Enzymes in steroid synthetic pathway not working - congenital adrenal hyperplasia

Question 4

What are examples of autoimmune disorders in the endocrine system?

Answer 4

Primary hypothyroidism
Graves disease
Type 1 diabetes
Hypophysitis

Question 5

What are signs and symptoms of adrenocortical failure?

Answer 5

Postural hypotension
Vitiligo
Skin Pigmentation - buckle and in scars
Really tiredness
Loss of weight
Muscular dystrophy

Question 6

What does the adrenal gland look like in different causes of adrenocortical failure?

Answer 6

Atrophied in autoimmune
Granulomas in TB
Other cancers can metastisise to the adrenals and stop them working

Question 7

What are consequences of adrenocortical failure?

Answer 7

Fall in BP
Loss of salt in urine
Increase plasma K
Fall in glucose due to glucocorticoid deficiency
High ACTH increasing pigmentation
Eventual death due to severe hypotension

Question 8

Why does glucose fall in adrenocortical failure?

Answer 8

No cortisol and cortisol is used to mobilise glucose

Question 9

Why does adrenocortical failure cause pigmentation?

Answer 9

Body increases ACTH to try kickstart the formation of aldosterone but no adrenal glands to make this but ACTH goes up and up and the precursor to ACTH is POMC which breaks down into MSH (melanocyte maker) and ACTH

Question 10

Where is POMC synthesised?

Answer 10

In pituitary

Question 11

What is POMC broken down into?

Answer 11

ACTH
MSH
Endorphins
Enkephalins
Other peptides

Question 12

Test for Addisons?

Answer 12

Normally 9am cortisol is high, if it is low at 9am and ACTH is high then it is a sign

Give a short synACTHen test - give 250 ug synacthen IM and measure cortisol response. If cortisol doesn’t rise a huge amount- confirms Addisons

Question 13

What is the commonest cause of congenital adrenal hyperplasia?

Answer 13

21 hydroxylase deficiency

Which can be complete or partial

Question 14

What hormones will be deficient in 21 hydroxylase deficiency?

Answer 14

progesterone -> 11 deoxycorticosterone -> aldosterone

17 OH prog -> 11 deoxycortisol -> cortisol

Question 15

How long can you survive with 21 hydroxylase deficiency?

Answer 15

Less than a few weeks

Question 16

What hormone will be in excess in 21 hydroxylase deficiency?

Answer 16

Sex steroids - particularly testosterone

Question 17

Why is the excess steroid in 21 hydroxylase deficiency bad?

Answer 17

Virilised - Too much androgen in utero so might need to karyotype baby to make sure is female baby or male because the female babies will look like male (enlarged clitoris or penis)

Question 18

Why do partial 21 hydroxylase deficiency patients normally turn up to clinics later in life?

Answer 18

Normally had enough cortisol and aldosterone to keep them out of trouble - women has hirsutism or male with early/accelerated puberty

Question 19

Problems that occur in 17 hydroxylase deficiency

Answer 19

Hypertension
Low K
Sex steroid deficiency
Glucocorticoid deficiency

Question 20

What can 11 hydroxylase deficiency cause?

Answer 20

It is a mineralocorticoid and behaves like aldosterone so sodium and water in potassium out, hypertension and hypokalaemiaa

Question 21

What are problems that can occur in 11 hydroxylase deficiency?

Answer 21

Virilisation
Hypertension
Hypokalaemia