Final answer:
The question is about a newborn with ambiguous genitalia and symptoms indicating an electrolyte imbalance, which is suggestive of congenital adrenal hyperplasia, particularly 21-hydroxylase deficiency. The diagnosis can be confirmed through blood measurement of 17-hydroxyprogesterone, and the treatment involves hormone replacement therapy.
Step-by-step explanation:
The clinical presentation of a newborn child with ambiguous genitalia, vomiting, decreased sodium (hyponatremia), increased potassium (hyperkalemia), and acidosis is suggestive of congenital adrenal hyperplasia (CAH), specifically 21-hydroxylase deficiency, which is the most common cause of CAH.
The diagnosis is often made based on clinical presentation and lab findings, including blood electrolyte levels and hormone concentrations. The definitive test for 21-hydroxylase deficiency is the measurement of 17-hydroxyprogesterone levels in the blood. Elevated levels are indicative of the condition. The treatment typically includes glucocorticoid replacement to reduce adrenal androgen production and mineralocorticoid replacement to address salt loss.