7. Hypoadrenal

Question 1

Consequences of adrenocortical failure

Answer 1

Fall in BP
Hyponatraemia + Hyperkalaemia
Fall in glucose
No negative feedback on ACTH -> High ACTH
MSH (melanocyte-stimulating hormone) is released at the same time as ACTH -> Pigmentation

Eventual death due to HYPOTENSION

Question 2

2 types of Addison’s disease

Answer 2

Tuberculous

Autoimmune

Question 3

Test for addisons

Answer 3

Low 9am cortisol
High ACTH
Short synACTHen test (im injection, normal person’s cortisol should go up)

Question 4

Treatment for addisons

Answer 4

1. IV normal saline 0.9% to normalise BP

2. High dose hydrocortisone IV/IM

Question 5

A baby girl was born with complete deficiency of aldosterone and cortisol. She has ambiguous genitalia. What enzyme is affected? Treatment?

Answer 5

Complete 21-hydroxylase deficiency
Can only survive for 24 hours
17-OH progesterone made in EXCESS -> excess sex steroids (testosterone in particular)
Baby with this condition would be hypotensive and have too much sex steroids
Ambiguous genitalia because she has been virilised by testosterone

Treatment: Saline IV (for BP) and measure steroid levels, then give steroid replacements

Question 6

How would partial 21-hyd. deficiency present?

Answer 6

Partial deficiency of aldosterone + cortisol
Doesn't present as a baby.
Later in life:
Girls - Hirsutism/virulisation
Boys - Precocious puberty

Slightly low BP (low aldosterone)
Mild fatigue (low cortisol)

Question 7

Woman has hypertension, hypokalaemia and virilisation. What enzyme is likely affected?

Answer 7

11-hydroxylase deficiency
Deficiency of cortisol + aldosterone
BUT excess 11-deoxycortisone = aldosterone-like effects
This causes hypertension/hypokalaemia

Sex steroids also in excess so virilisation

Question 8

Patient has had no puberty. He also has fatigue, hypertension/hypokalaemia and low glucose. What enzyme is affected?

Answer 8

17-hydroxylase
Causes deficiency of cortisol (fatigue, low glucose) and sex steroids (no puberty)

Results in excess aldosterone + 11-deoxycorticosterone (which causes hypertension/hypokalaemia)

Question 9

Patient is 8 yr old boy who is showing signs of puberty. Mild hypotension and slightly fatigued. What enzyme is likely affected?

Answer 9

Partial 21-hydroxylase deficiency

Question 10

Patient is 11 yr old girl who is showing male pattern of growth of hair. What enzyme is likely affected?

Answer 10

Partial 21-hydroxylase deficiency