ABSTRACT
In exclusively breastfed newborns, hypernatremic dehydration is associated with a free water deficit secondary to insufficient fluid intake. Failure of newborns to regain their birth weight by the 10th day of life should be investigated urgently. In this report, we present a case of a 2 -week-old girl who presented to our institution for 30% weight loss and was found to have severe hypernatremic dehydration associated with acute renal failure (creatinine 4 mg/dL). Upon further investigation, the breast milk sodium content was found to be extremely elevated (90 mEq/L). To our knowledge, the following reported case of severe neonatal hypernatremic dehydration associated with acute renal failure has the most elevated breast milk sodium content, serum sodium, and serum creatinine levels described in the literature. Thus, hypernatremic dehydration secondary to elevated breast milk content should always be borne in mind and investigated whenever suspected.
