Eosinophilia-myalgia syndrome in Wisconsin

Eosinophilia-myalgia syndrome (EMS) is a newly recognized illness characterized by intense eosinophilia, debilitating myalgia, and absence of any condition that could account for the eosinophilia or myalgia. The disorder has previously been associated with ingestion of capsules containing the amino acid L-tryptophan. In 1989, the Wisconsin Division of Health began surveillance for EMS. Each of 25 persons reported with the illness and meeting a standardized case definition were using L-tryptophan when their symptoms began, between June 1989 and January 1990. The median age of the patients was 43 years (range 26-82 years); 92% were female, and 96% were white. The majority of patients reported were using L-tryptophan for insomnia (36%), premenstrual syndrome (28%), or depression (20%). Common signs and symptoms in these cases included cough or dyspnea (60%), arthralgia (44%), edema of the extremities (44%), fever (36%), and rash (32%). Other epidemiologic investigations to date suggest that EMS may be associated with a product contaminant.