Clinical Case #1: Muscular System - Medicine
Case: Weakness
Introduction
Thyrotoxic periodic paralysis is a well-established phenomenon. When the symptoms of thyrotoxicosis are separated from the clinical picture, many features of this disease are identical to those of familial hypokalemic (Decrease in Potassium) periodic paralysis. Patients with thyrotoxic periodic paralysis have recurrent muscular weakness of the four extremities, affecting mainly the lower extremities. The onset of paralytic attacks usually coincides with the onset of hyperthyroidism, though overt findings of thyrotoxicosis are rarely present with the initial paralytic attack (as exemplified in our case 1 patient). In some cases, the periodic paralysis is the sole manifestation of the hyperthyroidism. A clinically distinguishing characteristic of thyrotoxic periodic paralysis includes predominance in men, with a male-to-female ratio of 11:1.2 This is in contrast to hyperthyroidism alone in the general population, in which women are predominantly affected. The age of onset is usually in the third to fifth decades of life.
