[A case of the eosinophilia-myalgia syndrome]

The Eosinophilia-myalgia syndrome (EMS) is a recently described clinical entity consisting of severe myalgia and eosinophilia that has ascribed to the ingestion of the amino acid L-tryptophan. Over 1500 cases of EMS have been reported to the Centers for Disease Control of United States as of June 1990. We report a case of EMS associated with the ingestion of L-tryptophan. A 24-year-old woman was admitted to our hospital due to severe myalgia. She had swelling on extremities and eosinophilia (1880/mm3). Full thickness biopsy of affected portion showed inflammation of fascia with eosinophils and histiocytes, which were compatible with eosinophilic fasciitis. She had a history of ingestion of fitness protein tablets bought at Hawaii for 3 months from Sep. to Dec. 1989, which contained the amino acid L-tryptophan. On the basis of these findings, we diagnosed her as EMS. It is suggested that this case is rare and important in Japan.