Pseudohypoaldosteronism in a neonate presenting as life-threatening arrhythmia

Neonatal hyperkalemia and hyponatremia are medical conditions that require an emergent diagnosis and treatment to avoid morbidity and mortality. Here, we describe the case of a 10-day-old female baby presenting with life-threatening hyperkalemia, hyponatremia, and metabolic acidosis diagnosed as autosomal dominant pseudohypoaldosteronism type 1 (PHA1). This report aims to recognize that PHA1 may present with a life-threatening arrhythmia due to severe hyperkalemia and describes the management of such cases in neonates. LEARNING POINTS: PHA1 may present with a life-threatening arrhythmia. Presentation of PHA can be confused with congenital adrenal hyperplasia. Timing and appropriate medical management in the critical care unit prevented fatality from severe neonatal PHA.