Objectives PHA1 is a rare heterogeneous disorder featured by changes in renal electrolyte transport due to mineralocorticoid resistance. The aim of the current study is to report the case of a child with 5-year follow-up presenting mutation in the ElaC Ribonuclease Z 2 (ELAC2) gene and clinical-laboratory diagnosis of pseudohypoaldosteronism type 1 (PHA1), as well as atypical clinical manifestations such as thrombocytosis, borderline aldosterone levels, and plasma renin activity. Case presentation The patient was treated with corticosteroids and salt replenishment. His cardiological condition presented gradual regression and the introduction of new food items in his diet dismissed the need of salt replenishment. Conclusions This new molecular mechanism should be taken into consideration in differential diagnoses in children with hyperkalemia, hyponatremia, delayed growth, hypertension and hypertrophic cardiomegaly.