Congenital Adrenal Hyperplasia?

Congenital Adrenal Hyperplasia (CAH) is a genetic (inherited) condition in which there is a decrease in the level cortisol in the bloodstream and an increase in the level of androgens.

Cause

CAH is caused by a problem with the feedback system which controls the production of adrenocorticotrophic (ACTH). The level of cortisol in the bloodstream is low, there is never enough produced to slow the release of ACTH from the pituitary gland. This means the adrenal glands are continually stimulated and become enlarged (hyperplasia).

Over stimulation means excess of hormones leak out into the blood stream. One of these is testosterone which causes the virilising features seen in the condition. Aldosterone production is also reduced. A drop in this hormone can affect salt levels in the bloodstream.

There are two types of CAH

Classic Form – This is the most severe form. There are two sub types’ salt losing and non-salt losing. Classic form affects 1 in 18,000 births (75% being salt losing and 25% non-salt losing)*. Similar numbers of boys and girls are affected but boys tend to have more severe symptoms.

Classic form symptoms in girls

Usually diagnosed soon after birth because of unusual looking genitalia. The clitoris may be larger than normal. The urethra and vagina may merge. The uterus and other female organs are normal. Early diagnosis means that baby girls do not normally become seriously ill through complications.

Classic form symptoms in boys

Baby boys look normal although the skin may be darker than usual. The penis may be enlarged. Other symptoms are dependent on salt losing or non-salt losing. For baby boys with salt losing form this is a serious condition. It can lead to a salt losing crisis usually between 7-14 days after birth. Symptoms would include vomiting, weight loss, extreme tiredness, dehydration and collapse.

Non-salt losing form in boys is usually diagnosed as a result of early virilisation. By the age of 2-4 the penis is enlarged and body hair visible.

Non Classic form – is less severe and more common affecting 1 in 1,000 *. This form tends to be diagnosed in later childhood or early adulthood.

Symptoms in males are that they may become sexually active at an early age i.e. early development of public and axilla hair, enlarged penis and height spurt.

Symptoms in females include early sexual development, pubic and axilla hair, height spurt.

Additionally:

• Excess body and facial hair in masculine distribution (hirsutism)
• Infertility
• Light periods (oligo menorrhoea)
• Lack of periods (amenorrhoea)
• PCOS
• Acne

Sexuality may be affected becoming less feminine in appearance and behaviour.