Newly Diagnosed Hypokalemic Periodic Paralysis Triggered by COVID-19.

Hypokalemic periodic paralysis (HypoPP) is a rare genetic disorder characterized by low potassium levels and episodic periods of muscle weakness. HypoPP has previously been attributed to numerous viral infections; however, cases related to coronavirus disease 2019 (COVID-19) are extremely limited. The current case is thus unique and involves a healthy 23-year-old male who presented to the emergency department after several uncharacteristic falls and three days of upper and lower extremity weakness. Initial labs revealed a potassium level of 1.1 mmol/L as well as being COVID-19 positive. Potassium supplementation helped stabilize his levels and relieved all of his symptoms. Based on an extensive clinical workup and significant family history of the mother and maternal grandmother with weakness in the setting of hypokalemia, a diagnosis of HypoPP was made. Upon discharge, he was placed on potassium-sparing diuretics to help prevent further symptom relapse and advised to complete genetic testing. With the high likelihood of the virus being endemic for years to come, clinicians should remember to consider HypoPP with patients with muscle weakness, especially in patients with concurrent COVID-19 infection, to minimize unnecessary workup and prevent potentially life-threatening symptoms of hypokalemia.