Endocrine

Question 1

What is the most common cause of congenital adrenal hyperplasia?

Answer 1

21 hydroxylase deficiency

Question 2

What will happen if there is a deficiency in 21 hydroxylase?

Answer 2

It is an important enzyme in the formation of cortisol and aldosterone, causing increased production of androgens

Question 3

What is the result of increased androgens in 21 hydroxylase deficiency CAH?

Answer 3

Precocious puberty in boys and ambiguous genetalia in girls

Question 4

What is DKA?

Answer 4

A metabolic state in which insulin deficiency has lead to build up of counter-regulatory hormones such as glucagon which stimulate catabolic processes such as B-oxidation of fatty acids resulting in ketones and hyperglycaemia

Question 5

How is DKA managed?

Answer 5

Give insulin and potassium

Careful fluid resuscitation

Question 6

Why should fluid resuscitation be careful in DKA?

Answer 6

risk of cerebral oedema, especially in children

Question 7

How do you calculate the fluid requirement in DKA?

Answer 7

hourly rate = (48h maintenance + dehydration deficit) - fluid already given for resus / 48