Tryptophan Toxicity: A Pharmacoepidemiologic Review of Eosinophilia-Myalgia Syndrome

Abstract

Tryptophan, an essential amino acid commercially available as a dietary supplement, has been implicated in the development of a new and potentially fatal clinical entity: eosinophiliamyalgia syndrome (EMS). EMS reached epidemic proportions in the US in late 1989 and early 1990, with 1536 cases and 27 deaths reported as of August 1990. Features of the syndrome include intense, debilitating myalgias and marked peripheral eosinophilia. Vasculitis, neuropathy, and pulmonary involvement also may be observed but are not pathognomonic. Death typically ensues from ascending polyneuropathy with resulting paralysis and respiratory arrest. Treatment involves discontinuation of tryptophan ingestion. Administration of prednisone may not always alleviate or reverse the symptoms. Recovery is generally slow. The etiology of EMS has been traced to a contaminant in the bulk manufacturing process of tryptophan by a single Japanese company. Efforts are currently underway to confirm the structure of the contaminant by laboratory synthesis and to define its biologic and toxic effects using an animal model for EMS.

Optimized medium via statistical approach enhanced threonine production by Pediococcus pentosaceus TL-3 isolated from Malaysian food

“…Currently, threonine production relies heavily on fermentation method by using modified strains of Corynebacterium glutamicum [6] and Escherichia coli [7]. However, pathogenicity of these microorganisms could raise concern for the consumers, whereby utilization of genetically engineered bacteria for amino acid production has its share of controversies particularly after the eosinophils myalgia syndrome (EMS) outbreak in 1980s attributed to the toxin produced by an engineered bacterium [8]. This has urged for continuous search of a safer alternative food grade amino acid producer.…”

Predicting Metabolite–Disease Associations Based on LightGBM Model

“…For example, L-proline (Nadler et al, 1988) is one of metabolic characteristics of asthma, which is supported by experimental asthma models and clinical studies in children and adults (Pite et al, 2018). Another example is L-tryptophan (Hartzema et al, 1991), which has long been suggested to be relevant to the pathophysiology of asthma (Hu et al, 2020).…”

Drug-Induced Eosinophilia

“…Отдельно необходимо отметить аминокислоту триптофан, которую используют в качестве анти депрессанта и биологически активной добавки к пище. Применение триптофана может вызы вать развитие потенциально фатального синдро ма эозинофилиимиалгии (EosinophiliaMyalgia Syndrome, EMS) [62], сопровождающегося эози нофилией, тяжелой миалгией, отеком и кожной сыпью. Также могут поражаться другие органы, чаще всего печень и центральная нервная система [63].…”