Challenges of Diagnosing Pseudohypoaldosteronism (PHA) in an Infant

Background. Pseudohypoaldosteronism (PHA) is characterized by renal tubular resistance to aldosterone. As a result, the symptoms typically involve hyperkalemia and hyponatremia. The aim of this clinical case report is to highlight the severe electrolyte imbalance PHA can present within an infant, as well as difficulties in diagnosing the condition. Case Presentation. A 5-week-old male arrived at the ER with episodes of emesis, lethargy, and difficulty in feeding. He had significant electrolyte abnormalities and was being treated by his PCP for failure to thrive. He presented with urinary sodium wasting, indicated by hyponatremia, hyperkalemia, low chloride, and hypercalcemia. Patient was treated with IVF and NaCl supplementation to normalize the electrolytes. The patient showed heterozygosity for a variant in the WNK1 gene, which typically causes Gordon syndrome; however, our patient had a normal blood pressure. The electrolyte imbalance self-resolved during several months of follow-up, and currently, the patient is not on any treatment.