["Eosinophilia-myalgia" syndrome due to L-tryptophan containing products. Cooperative evaluation of French Regional Centers of Pharmacovigilance. Analysis of 24 cases].

By November 17, 1989, the MMWR published the 154 first reports of a syndrome consisting of myalgia and eosinophilia (EMS), occurring with the consumption of L-tryptophan containing products (L-TrpCp) and which might represent a new clinical entity. To standardize reporting over the country, the CDC of Atlanta developed the following case definition: 1) a peripheral blood total eosinophil count of more than 1 x 10(9) cells per liter 2) generalized myalgia sufficiently severe to affect a patient's ability to pursue daily activities 3) the exclusion of infections or neoplastic conditions. The FDA then, announced its intention to seek a nationwide recall of all tryptophan containing products, followed by other european countries (UK, Germany, France).