Variante patogénica CACNA1S como causa de parálisis periódica hipocalémica

Introduction: we present the case of a patient with hypokalemic periodic paralysis (HPP), which is a type of muscular channelopathy caused by a genetic alteration. Clinical case: a 13-year-old male adolescent with no significant family history. He started with episodes of flaccid paralysis of the four extremities upon awakening, the duration was variable, and without compromise of mental functions. In one of the episodes, severe hypokalemia (1.6 mmol/L) was documented, with recovery after electrolyte correction. HPP was suspected, requesting a genetic panel in which a heterozygous pathogenic variant was identified in the CACNA1S gene, classifying it as type 1 HPPH. Conclusions: HPP is a diagnostic and therapeutic challenge; its early identification can help to reduce comorbidities in these patients.