New born 7 days old with vomiting and dehydration clinical examination was normal except for hyperpigmentation of nipple. Electrolytes Na: 120 meq. K: 9 meq. mostlikelydiagnosis -
High-Yield Explanation
Congenital adrenal hyperplasia due to defect in CYP21A2 is suggested by episodes of acute adrenal insufficiency with hyponatremia , hyperkalemia , dehydration & vomiting ( Harrison 17 pg 2267)