Gastrointestinal involvement in L-tryptophan (L-Trp) associated eosinophilia-myalgia syndrome (EMS).

We report a 45-year-old female who had symptomatic gastrointestinal involvement, eosinophils in the cellular infiltrate, and who proved to have L-tryptophan-associated eosinophilia-myalgia syndrome. This case illustrates that gastrointestinal disease can be a major, seemingly primary clinical presentation in this syndrome, and that a drug history, specifically L-tryptophan, needs to be included in the differential diagnosis of "eosinophilic gastroenteritis."