Hypokalemic thyrotoxic paralysis: a rare cause of tetraparesis with acute onset in Europeans

We describe a 21-year-old Italian male affected by hypokalemic tetraparesis with acute onset. In the emergency ward, the patient was agitated, with ta chycardia (140/min) and systolic hypertension (180/70 mm Hg). He was not ab le to flex the lower extremities against a light resistence and furthermore , he was hypotonic and without tendon reflexes. One hour later he developed strength deficit of the upper extremities as well. Biochemical analyses re vealed severe hypopotassemia (2.1 meg/l). After administration of 140 meq p otassium phosphate, the patient began to improve, and 12 h after the onset he was able to walk normally. Successive investigations documented an undia gnosed case of Graves' disease. Thyrotoxic hypokalemic paralysis has been o bserved almost only in Asians, however, with this case and others reported, we believe that it should be considered as a cause of muscular paralysis a lso in Caucasians.