Congenital adrenal hyperplasia (CAH) is a group of inherited genetic disorders that affect the adrenal glands. It's characterized by a deficiency in one of the enzymes needed for the adrenal glands to produce hormones, particularly cortisol and, in some cases, aldosterone.

Causes

CAH is caused by mutations in genes that encode enzymes necessary for hormone production in the adrenal glands. The most common form is due to a deficiency in the 21-hydroxylase enzyme. These genetic mutations are inherited in an autosomal recessive pattern, meaning a child needs to inherit one copy of the mutated gene from each parent to develop the condition.

Symptoms

Symptoms of CAH vary depending on the specific enzyme deficiency and the level of enzyme activity. Common symptoms include:

  1. In Infants:
    • Salt-wasting Crisis: In severe cases, lack of aldosterone can lead to a life-threatening salt-wasting crisis in the first few weeks of life.

    • Ambiguous Genitalia in Females: Females may be born with ambiguous genitalia due to excess androgen production.

    • Rapid Growth in Childhood: But typically a shorter final height than expected.

  2. In Older Children and Adults:
    • Early Pubic Hair and Rapid Growth in Childhood: Due to excess androgen.

    • Severe Acne, Excessive Hair Growth, and Irregular Periods: In females.

    • Infertility: Can occur in both males and females.

    • Adrenal Crisis: Symptoms include vomiting, dehydration, low blood pressure, and shock.

Treatment

The treatment of CAH aims to replace the deficient hormones and control the symptoms:

  1. Glucocorticoid Therapy:
    • Hydrocortisone: Used in children due to its short half-life and growth-friendly profile.

    • Prednisone or Dexamethasone: Used in adults or older children.

  2. Mineralocorticoid Replacement:
    • Fludrocortisone: Used if aldosterone is deficient.

  3. Salt Supplements: In infants and young children to prevent salt-wasting crises.

  4. Monitoring and Adjusting Hormone Levels: Regular follow-up with an endocrinologist to monitor growth, development, and hormone levels, adjusting medications as necessary.

  5. Surgery: In females born with ambiguous genitalia, reconstructive surgery may be considered.

Medication

  • Hydrocortisone, Prednisone, Dexamethasone: To replace cortisol.

  • Fludrocortisone: For aldosterone replacement.

  • Salt Supplements: Particularly in cases with salt-wasting.

Regular monitoring is essential to ensure proper growth and development in children with CAH and to adjust treatment as needed. It's also crucial for patients with CAH to be aware of the signs of adrenal crisis and how to respond, including when to seek emergency medical attention.