An 8 days old male infant is brought to the emergency department with vomiting, lethargy, dehydration and features of shock. Clinical examination reveals hyperpigmentation of the genital skin and normal external genitalia. Abdominal examination is unremarkable. blood tests revealed sodium of 124 mecill, potassium of 7 meq/1 and hypoglycemia. Which of the following is the most likely diagnosis:
High-Yield Explanation
Presence of vomiting, lethargy, dehydration, hyponatremia, hyperkalemia, hypoglycemia and shock in this eight-year-old male infant suggest a diagnosis of neonatal adrenal insufficiency/crisis.
Congenital Adrenal Hyperplasia is the most prevalent cause of adrenal insufficiency in neonates (typically 7-14 days post delivery) and the single best answer amongst the options provided,
Clinical features of CAH (21 hydroxylase deficiency)
Symptoms of classical CAH due to 21 hydroxylase deficiency are:
Clinical: Lethargy, vomiting, Anorexia, weight loss, dehydration, hypotension, shock
Mineralocorticoid deficiency: Hyponatremia, hyperkalemia, hypotension
Cortisol deficiency: Hypoglycemia, Hyperpigmentation of areolar and scrotal areas in males and genital creases in females (due to ↑ ACTH secretion)
Excess Androgen
Males: Phenotypically normal for some years, precocious puberty
Females: Virilization (female pseudohermaphrodite)