An 8-day-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. Blood investigations reveal Sodium 124 mEq/L, potassium of 7 mEq/L and hypoglycemia. Which of the following is the most likely diagnosis?
High-Yield Explanation
a. Congenital Adrenal Hyperplasia (CAH)(Ref: Nelson's 20/e p 2714-2723, Ghai 8/e p 526-527)The given clinical scenario of dehydration, hyperpigmentation of genitalia and laboratory features of hypoglycemia, hyponatremia and hyperkalemia suggest a diagnosis of CAH due to 21 hydroxylase deficiency.