Congeita Adrenal Hyperplasia Flashcards
(50 cards)
What is congenital adrenal hyperplasia (CAH)?
A group of autosomal recessive disorders that impair adrenal steroid biosynthesis.
What hormone’s overproduction occurs due to cortisol deficiency in CAH?
Adrenocorticotropic hormone (ACTH)
What does elevated ACTH levels lead to in CAH?
Increased production of adrenal androgens
What is the most common cause of CAH?
21-hydroxylase deficiency (90%)
What is the result of 21-hydroxylase deficiency?
Impaired conversion of 17-hydroxyprogesterone to 11-deoxycortisol, leading to cortisol deficiency and excess androgen production.
What percentage of CAH cases is due to 11-beta hydroxylase deficiency?
5%
What clinical feature is associated with 11-beta hydroxylase deficiency?
Hypertension due to excess deoxycorticosterone
What is a very rare cause of CAH?
17-hydroxylase deficiency
What does 17-hydroxylase deficiency lead to?
Mineralocorticoid excess with low androgen and estrogen levels
What are common clinical presentations of CAH?
- Virilization
- Salt-wasting crisis
- Precocious puberty
- Infertility
- Height and growth abnormalities
What is a significant symptom of virilization in female infants with CAH?
Ambiguous genitalia
What percentage of 21-hydroxylase deficiency cases experience a salt-wasting crisis?
About 75%
What characterizes a salt-wasting crisis?
- Dehydration
- Hypotension
- Electrolyte imbalances
What can excess androgens in CAH lead to in both males and females?
Precocious puberty
What hormonal issue might adults with untreated CAH face?
Infertility
What growth issue is common in children with CAH?
Accelerated growth rates initially but shorter adult stature due to early epiphyseal closure.
What is the primary method for diagnosing CAH?
Screening for elevated levels of serum concentration of 17-hydroxyprogesterone (17OHP)
What testing confirms the diagnosis of CAH?
ACTH stimulation testing
What is the management strategy for CAH?
Glucocorticoid replacement to reduce ACTH levels and minimize adrenal androgen production.
What medication is prescribed in cases of mineralocorticoid deficiency in CAH?
Fludrocortisone
What are features of 21-hydroxylase deficiency?
- Virilisation of female genitalia
- Precocious puberty in males
- 60-70% have a salt-losing crisis at 1-3 weeks of age
What are features of 11-beta hydroxylase deficiency?
- Virilisation of female genitalia
- Precocious puberty in males
- Hypertension
- Hypokalaemia
What are features of 17-hydroxylase deficiency?
- Non-virilising in females
- Inter-sex in boys
- Hypertension
True or False: Excess liver IC can mimic congenital adrenal hyperplasia.
True
