Congenital adrenal hyperplasia due to 21-hydroxylase deficiency

Congenital adrenal hyperplasia due to 21-hydroxylase deficiency (21-OHD CAH) is an autosomal recessive genetic disorder affecting the adrenal glands. It is the most common form of congenital adrenal hyperplasia, accounting for approximately 95% of cases.

Overview

21-OHD CAH is caused by mutations in the CYP21A2 gene, which encodes the enzyme 21-hydroxylase. This enzyme is crucial for the production of cortisol and aldosterone, two important hormones produced by the adrenal glands. When 21-hydroxylase is deficient, the body cannot produce these hormones in sufficient amounts, leading to a variety of symptoms.

Symptoms

Symptoms of 21-OHD CAH can vary widely, depending on the severity of the enzyme deficiency. In severe cases, symptoms may appear in infancy or early childhood and can include salt-wasting crisis, virilization in girls, and early puberty in both sexes. In milder cases, symptoms may not appear until adolescence or adulthood and can include irregular menstruation, acne, and infertility.

Diagnosis

Diagnosis of 21-OHD CAH is typically made through blood tests to measure levels of hormones produced by the adrenal glands. Genetic testing can also be used to confirm the diagnosis and identify the specific mutation in the CYP21A2 gene.

Treatment

Treatment for 21-OHD CAH typically involves lifelong hormone replacement therapy to replace the deficient hormones. In some cases, surgery may be required to correct physical abnormalities.

The adrenal glands, located above the kidneys, are affected in 21-OHD CAH.

See also

• Congenital adrenal hyperplasia
• CYP21A2
• 21-Hydroxylase