Congenital Adrenal hyperplasia

Question 1

What is the cause of congenital adrenal hyperplasia?

(pathophysiology)

Answer 1

21- hydroxylase enzyme deficiency -> underproduction of glucocorticoids and overproduction of androgens

*in small number of cases it is 11-beta-hydroxylase deficiency

Question 2

the inheritance pattern of CAH

Answer 2

autosomal recessive

Question 3

The role of 21-hydroxylase enzyme

Answer 3

• 21-hydroxylase is the enzyme required to convert progesterone into aldosterone and cortisol
• Progesterone is also used to create testosterone, but this conversion does not rely on the 21-hydroxylase enzyme

Question 4

Why there is an excess of androgen in CAH?

Answer 4

• there is a lot of progesterone that is floating about that cannot be converted to aldosterone or cortisol (due to 21 alpha hydroxylase deficiency)
• it gets converted to testosterone instead
• The result is a patient with low aldosterone and cortisol and with abnormally high testosterone

Question 5

Presentation of a female baby with CAH

Answer 5

• virilised genitalia, known as “ambiguous genitalia”
• enlarged clitoris

This is due to the high testosterone levels

Question 6

(3) electrolytes abnormalities in babies with CAH

Answer 6

Patients with more severe CAH present shortly after birth patients develop

• Hyponatraemia
• Hyperkalaemia
• Hypoglycaemia

Question 7

Symptoms seen in babies with severe CAH

Answer 7

• Poor feeding
• Vomiting
• Dehydration
• Arrhythmias

Question 8

Symptoms in a baby with CAH

Answer 8

• Poor feeding
• Vomiting
• Dehydration
• Arrhythmias

Question 9

When do patients with less severe CAH present?

Answer 9

Childhood or after puberty

Question 10

What (1) hormonal abnormality are the symptoms related to in less severe CAH (late presentation)?

Answer 10

high androgen levels

Question 11

Symptoms in girls with less severe CAH

Answer 11

• Tall for their age
• Facial hair
• Absent periods
• Deep voice
• Early puberty

Question 12

Symptoms with boys with less severe CAH

Answer 12

• Tall for their age
• Deep voice
• Large penis
• Small testicles
• Early puberty

Question 13

What is the textbook/exam clue for a patient with CAH?

Answer 13

Hyperpigmentation of the skin

Question 14

Management of CAH

Answer 14

• Coordinated by paediatric endocrinologists
• Cortisol replacement
• Aldosterone replacement
• Female patients with “virilised” genitals may require corrective surgery