[Thyrotoxic hypokalemic periodic paralysis: 18 cases with different forms of thyrotoxicosis]

Thyrotoxic periodic paralysis (TPP) is a rare complication of thyrotoxicosis in whites but it is commonly reported in oriental populations. Eighteen males with TPP were studied from 1966 to 1993 (17 years) with a mean age of 32.8 years (range: 22-50 years). Their ancestor, traced back as possible, was hispanic in 15 and autoctonous indigens (mapuche) in three. They had one or more episodes of flaccid paralysis with complete recovery associated with thyrotoxicosis and hypokalemia (in the twelve patients who had their serum potassium determined). Two patients had respiratory compromise. Ten patients had their crisis onset after physical exertion and/or copious ingestion of carbohydrates. Only one of the patients had severe thyrotoxicosis and the diagnosis was made after the periodic paralysis in ten of them. The types of thyrotoxicosis associated with TPP were: Graves-Basedow disease in 13, subacute thyroitidis in three, and overdosage of thyroid hormone in two patients. In summary, TPP can occur in latin american populations, may be fatal, and is not always associated with Graves-Basedow disease.