Patients with 21-hydroxylase deficiency usually appear underweight and dehydrated. Physical examination is usually remarkable for hypotension and virilization.

Common physical examination findings of 21-hydroxylase deficiency include:^{[1][2][3][4][5]}

• Classic salt wasting type:
  • Infants may be underweight and dehydrated
• Pre-pubertal changes:
  • May have tall stature, increased muscle mass, acne, and adult body odor

• Classic salt-wasting type: hypotension
• Reflex tachycardia

• Hirsutism
• Alopecia
• Deep voice
• Acne

• Acne
• Hyperpigmentation

• Females in classic type may exhibit:
  • Genital ambiguity
  • Labial fusion

• Female in non-classic type may have:
  • Clitoromegaly
• Male in classic type may have:
  • Penile enlargement
  • Testicular mass
  • Hyperpigmentation of the scrotum
  • Early virilization at two to four years of age with pubic hair growth, growth spurt, adult body odor
• Male in non-classic type:
  • Normal appearing at birth.

• Female:
  • Male-typical cognitive pattern (better performance on spatial tasks, worse performance on verbal tasks)
  • Cross-gender role behavior
  • Lower intelligence quotients (IQ)

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