Transient Pseudohypoaldosteronism: A Rare Cause of Severe Hyponatremia in a Baby

Hyponatremia and dehydration in children represent a medical emergency due to a variety of underlying illness. Other than an evidence of gastroenteritis with diarrhea and vomiting (which is the major cause of hypoosmolar hyponatremia in pediatric age), other causes should be considered, especially if there is evidence of hyperkalemia and high sodium fraction excretion (FENa), like iatrogenic causes (diuretic excess), transient or genetic abnormalities of the renal mineralocorticoid pathway, syndrome of inappropriate anti-diuretic hormone secretion (SIADH), acute renal failure, congenital adrenal hyperplasia (CAH). Here we present a case of transient pseudohypoaldosteronism in a 2 months old baby secondary to urinary tract infection, who presented with a history of poor sucking, fever and dehydration.