Med Gene_Pediatrics

Terms in this set (113)

A full-term infant was born with ambiguous genitalia (Panel A). There was no family history of similar presentations or known genetic disorders. The neonate was noted to have sinus tachycardia with a heart rate of up to 179 beats per minute without hypotension. Laboratory evaluation revealed an elevated potassium level of 7.4 mmol per liter (normal range for all persons, 3.5 to 5.3), a low sodium level of 125 mmol per liter (normal range, 135 to 148), an elevated 17-hydroxyprogesterone level of 196.0 μg per liter (593.0 nmol per liter; normal range, 0.5 to 2.4 μg per liter [1.5 to 7.0 nmol per liter]), and a testosterone level of more than 15.0 ng per milliliter (52.0 nmol per liter; normal range, 0.1 to 0.8 ng per milliliter [0.3 to 2.8 nmol per liter]). Ultrasonography of the abdomen revealed bilateral adrenal hypertrophy without visible testes, and chromosomal analysis revealed the 46 XX karyotype. Salt-losing congenital adrenal hyperplasia due to 21-hydroxylase deficiency in a female infant was diagnosed. The ambiguous genitalia, which is characterized by hypertrophy of the clitoris and labia majora and the presence of a urogenital sinus, may resemble hypospadias with cryptorchidism in males. Medical management of electrolyte abnormalities, intravenous fluids, and glucocorticoid and mineralocorticoid replacement were initiated. At 2 years of age, the patient underwent complex surgical reconstruction, including repair of the urogenital sinus (Panel B, black arrow), clitoroplasty (arrowhead), and vaginoplasty (white arrow). The patient has regular follow-up and is doing well with glucocorticoid and mineralocorticoid replacement therapy.