Eosinophilia-myalgia syndrome

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**Eosinophilia-myalgia syndrome**
*Classification & external resources*
ICD-9	710.5
DiseasesDB	32044
eMedicine	derm/891

Eosinophilia-myalgia syndrome (EMS) is an incurable and sometimes fatal flu-like neurological condition that is believed to have been caused by ingestion of L-tryptophan supplements. Similar to regular eosinophilia, it causes an increase in eosinophil granulocytes in the patient's blood.

1 History
2 Recent developments
3 Reference
4 See also
5 External links

[edit] History

Eosinophilia-myalgia syndrome was first recognized after the doctors of 3 women with mysterious symptoms talked together in 1989. However, many people became ill as long as 2-3 years before the illness was reported to the Centers for Disease Control and Prevention in November of 1989. Rheumetologists experienced a large surge of new patients with mysterious symptoms during this period. It is possible that as many as 60,000 individuals became ill from using L-tryptophan. Epidemologists traced the cause to consumption of L-tryptophan from a single manufacturer. The company supplied the majority of L-tryptophan to the United States under various brand names. There was evidence that new batches of L-tryptophan had been improperly prepared. Fist, the specific bacterial culture used to synthesise this tryptophan had recently been genetically engineered to greatly increase tryptophan production. Second, shortcuts had been taken in the purification process to reduce costs. For example, a purification step that used charcoal absorption to remove impurities had been modified to reduce the amount of charcoal used. Additionally, these batches were grown in open vats in a fertilizer factory. It is possible that one or more of these modifications and/or the environment for manufacture allowed new or greater impurities through the purification system. The specific impurity (or impurities) responsible for the toxic effects was never firmly established, although several impurities were proposed as the cause, and their chemical structures determined. Regardless of the origin of the toxicity, L-tryptophan was banned from sale in the US in 1989; and other countries followed suit. In February 2001, the FDA loosened the restrictions on the marketing of tryptophan (though not on importation).

[edit] Recent developments

Recent research from FDA has shown that the association of EMS with a specific brand of tryptophan supplement may be false (Smith & Garrett, 2005). Many brands of tryptophan supplements are now known to be associated with this medical condition, which may be caused by tryptophan interference with toxic histamine metabolism. It is suggested that histamine then accumulates and causes the EMS syndrome.

[edit] Reference

Bolton, Penni, Carl Edwin Lindgren (September/October 1991). A Mystery Ailment Revealed. American Fitness, Vol. 9, No. 5 p. 34-5.
Smith MJ, Garrett RH. A heretofore undisclosed crux of eosinophilia-myalgia syndrome: compromised histamine degradation. Inflamm Res. 2005 Nov;54(11):435-50. See: [1]
Walker,Larry, Carl Edwin Lindgren, Penni Bolton. (1991). L-Tryptophan induced eosinophilia-myalgia syndrome. The Journal of the Royal Society of Health, Volume 111, Number 1: 29-30.