Diagnosis

Diagnosis of congenital adrenal hyperplasia may include the following tests.

Prenatal testing

Tests to diagnose CAH in fetuses can be done when siblings have the disease or family members are known to carry the gene defect. One of these tests may be done:

  • Amniocentesis. This procedure involves using a needle to withdraw a sample of amniotic fluid from the womb, and then examining the cells.
  • Chorionic villus sampling. This test involves withdrawing cells from the placenta for examination.

Newborns, infants and children

All newborns in the United States are screened for classic CAH caused by genetic 21-hydroxylase deficiency during the first few days of life. This test does not identify nonclassic CAH.

Diagnosis of CAH includes:

  • Physical exam. The doctor examines your child and evaluates symptoms. If, based on these findings, the doctor suspects CAH, the next step is to confirm the diagnosis with blood and urine tests.
  • Blood and urine tests. Tests used to diagnose CAH measure levels of hormones produced by the adrenal glands. A diagnosis can be made when there are abnormal levels of these hormones.
  • Gene testing. In older children and young adults, genetic testing may be needed to diagnose CAH.
  • Testing to determine a child's sex. In female infants who have severe ambiguous genitalia, tests can be done to analyze chromosomes to identify genetic sex. Also, pelvic ultrasound can be used to identify the presence of female reproductive structures such as the uterus and ovaries.