Thyrotoxic Periodic Paralysis: An Under-Recognized Cause of Paralysis in Young Hispanic Men

Background: Patients presenting to the emergency department with paralysis can have a wide differential diagnosis. Thyrotoxic periodic paralysis (TPP) is a rare disorder causing transient flaccid paralysis in the setting of thyrotoxicosis and hypokalemia. It has been reported in Asian male populations predominantly, and the diagnosis is rarely considered in non-Asian populations. Recent research has identified cases in patients with diverse ethnic backgrounds, although epidemiologic data from the United States are very limited. Objective: Our aim was to report our experience with TPP at a tertiary care center in the United States. Methods: A retrospective chart review was conducted between January 2006 and February 2022 to identify cases of TPP and determine their demographic and clinical characteristics. Prevalence of TPP was estimated using the institutional hyperthyroidism registry. Results: Thirty-three patients with TPP were identified. All of the patients were male; median age was 28 years, and 85% were Hispanic. All patients had hypokalemia at presentation and 23% had rebound hyperkalemia after treatment. Prevalence of TPP in our population of patients with hyperthyroidism was approximately 0.5%. Conclusions: Young Hispanic men presenting with paralysis should be evaluated for TPP, as the prevalence in this population may be higher than estimated previously. Management of TPP involves treatment of underlying hyperthyroidism and cautious potassium repletion, with an initial dose of no more than 60 mEq/L of potassium chloride to avoid rebound hyperkalemia.