A Neonate With Excessive Weight Loss and Electrolyte Abnormalities

A 7-day-old girl was brought to the hospital for excessive weight loss. Initial evaluation revealed electrolyte abnormalities, including hyponatremia and hyperkalemia. Stepwise assessment was undertaken to evaluate potential endocrine, renal, and metabolic causes, with supportive interventions initiated. Over the course of hospitalization, her electrolytes and weight gradually improved. Further workup, including imaging and genetic testing, was performed to clarify the underlying etiology. Our panel of experts first discuss the approach to weight loss in neonates and then review the assessment and management of neonatal electrolyte disturbances, highlighting endocrine, renal, and genetic considerations that may guide clinical care.