Periodic paralysis in children: case report and review of Japanese literature.

An 8-year-old boy with familial hypokalemic periodic paralysis is described. Twenty eight cases of periodic paralysis under 15 years of age were collected from the Japanese literature and reviewed. Serum potassium concentrations during an attack of paralysis were recorded in 27 cases including our case: 20 cases were hypokalemic, 4 were normokalemic and 3 were hyperkalemic. Hypokalemic periodic paralysis was more frequent in rnales than in females among adult patients in Europe and the United States, and especially so in Japan and China. Moreover, hyperthyroidism was frequent · in Japanese and Chinese adults with hypokalemic periodic paralysis, especially in male~, but rare in. Europeans and Americans. However, there was no sex difference, and none of these _pediatric patients had hyperthyroidism in Japan.