Objective: Rare disease Background: Pseudohypoaldosteronism (PHA) is characterized by renal tubular resistance to aldosterone and leads to hy-ponatremia, hyperkalemia, and metabolic acidosis. PHA is divided into 2 types: PHAI and PHAII. PHAI can be dominant (systemic disease) or recessive (renal form). PHAII causes hypertension with hyperkalemia and is recognized mostly in adults. PHA can be a life-threatening disease due to salt-wasting syndrome and severe hypovolemia. Case Report: We describe the case of a 2-month-old girl who was admitted to our hospital with hypovolemic shock due to salt -wasting syndrome. Laboratory tests revealed severe electrolyte abnormalities: hyponatremia (Na-116 mmol/L), hyperkalemia (K-10 mmol/L) and metabolic acidosis (pH-7.27; HCO3-12 mmol/L). Serum aldosterone was >100 ng/dL. Genetic analysis confirmed mutations in SCNN1A and CUL3 gene responsible for PHAI and PHAII. Supplementation with NaCl, pharmacological treatment of hyperkalemia, and restriction of potassium in the diet resulted in the normalization of serum electrolytes and proper future development. Conclusions: Pseudohypoaldosteronism should always be considered in the differential diagnosis of hyponatremia and hy-perkalemia in children. Salt loss syndrome can lead to hypovolemic shock and, when unrecognized and un-treated, to death of a child due to arrythmias and brain edema. The presence of 2 types of PHA in the same patient increases the risk of salt loss and at the same time significantly increases the risk of hypertension be-cause of genetic predisposition and regular diet. Increased salt concentration in sweat and saliva may suggest pseudohypoaldosteronism.
