The eosinophilia-myalgia syndrome: current concepts and future directions.

The eosinophilia-myalgia syndrome (EMS) is a recently described systemic disorder distinguished by the development of characteristic muscle spasm, myalgia, neuropathy, and scleroderma-like cutaneous induration. Life-threatening manifestations have included cardiopulmonary and acute ascending neuropathic syndromes. Current evidence indicates that this is a severe illness with the potential for long-term disability. Careful follow-up studies will help to better define new features of this disease, such as the recent awareness of severe neurocognitive abnormalities in some patients. The association of EMS with the ingestion of L-tryptophan may provide important clues toward the understanding of idiopathic fibrosing syndromes, as well as toxin-induced autoimmune phenomena. Rational therapy will be dependent upon a more complete understanding of the pathogenesis of this and related diseases.