RESUMO
A pre-term baby girl was born following a pregnancy complicated by severe polyhydramnios at a gestational age of 36 weeks. She was initially suffering from respiratory distress consistent with idiopathic respiratory distress syndrome, and altered electrolyte imbalance with hyponatremia, hypokalemia and hypochloremic metabolic alkalosis. However, during the third week of life when she had dehydration along with significant electrolyte imbalance, Bartter's syndrome was considered which was supported by findings of high renin and aldosterone levels. Treatment was done by correction of electrolytes and dehydration along with indomethacin. The drug was well tolerated. The infant showed correction of electrolyte imbalance. The features of this case suggest an extreme form of Bartter's syndrome presenting from the early days of life. The syndrome is reported because of it's rarity and alerts pediatricians to the antenatal and neonatal variant of Bartter's syndrome