Information on the following diseases can be found in the Related Disorders section of this report:

• Scleroderma
• Trichinosis
• Toxic Oil Syndrome
• Eosinophilia Fasciitis

Eosinophilia Myalgia Syndrome may make its presense known only weeks, months, or even years after the original period of high-volume consumption of L-tryptophan. L-tryptophan is an essential amino acid present in most foods. However, when it is purchased as a "health food", people often take doses much higher than would be present in the normal diet. The disorder is characterized by large amounts of eosinophils (white blood cells) in the blood. The primary symptom is severe muscle pain and weakness. There may also be associated ulcers of the mouth or other mucous membranes. Sore throat, difficulty breathing (dyspnea), swollen liver and abdomen, abdominal pain, and fever may also be present.

Skin abnormalities resembling Scleroderma, including swelling and tightening of the skin, painful itching, and edema, along with peau d'orange skin of the legs, may also occur. The skin symptoms usually start in the extremities (usually the legs) with the upper body becoming involved later if at all.

Eosinophilia Myalgia may be caused by the ingestion of some lots of oral L-tryptophan. Tryptophan is an essential amino acid present in very small quantities in most foods. However, the amounts ingested by patients with Eosinophilia Myalgia are over and above the amounts occuring naturally in food. The drug was formerly available at health food stores without prescription as a dietary supplement. Although there was no proof of effectiveness, many patients used it to treat depression, premenstrual syndrome and insomnia. During 1990 the FDA removed tryptophan from the shelves of stores and it can no longer be purchased in this country. Scientists are still trying to determine whether the tryptophan itself causes predisposed persons to manufacture neurotoxins that cause Eosinophilia Myalgia symptoms, or whether the tryptophan is in some way contaminated in the manufacturing process.

Scientists now believe they can confirm that L-tryptophan itself causes symptoms of EMS in patients who use the product. Further studies have shown that L-tryptophan contaminated with 1-1-ethylidenebis (ETB) causes more severe problems in people than regular L-tryptophan; still, L-tryptophan alone can cause EMS.

Eosinophilia Myalgia seems to affect males and females in equal numbers. The Centers of Disease Control states that as of February, 1990, 1269 cases were reported to them. Some patients have died.

Symptoms of the following disorders can be similar to those of Eosinophilia Myalgia. Comparisons may be useful for a differential diagnosis:

Scleroderma refers to a group of chronic disorders characterized by fibrosis, degenerative changes, and vascular abnormalities in the skin. Scleroderma is the chronic hardening and shrinking of the connective tissues of any part of the body, although the term literally means "hardening of the skin." (For more information on this disorder, choose "Scleroderma" as your search term in the Rare Disease Database.)

Trichinosis is a disorder that is caused by the parasitic round worm Trichinella spiralis. Persons become infected by eating raw or undercooked pork that contains cysts of the parasite. The symptoms include swelling of the eyelids, and mucous membranes. Aching of the muscles, fever, and increasing weakness may also be present.

Toxic Oil Syndrome was an epidemic disorder associated with the eating of contaminated cooking oil that swept Spain during the summer of 1981 and affected over 20,000 persons. Its features were an initial phase of fever and pneumonitis, then gastrointestinal dysfunction and severe eosinophilia, severe myalgia, muscle contractures and severe muscular pain.

Eosinophilic Fasciitis commonly occurs in the fourth to sixth decades of life. The initial symptoms may include pain, swelling and inflammation of the skin, which usually takes on a characteristic orange-peel appearance. The arms and forearms are affected more often than the thighs and legs. Arm and leg movements gradually become restricted. Inflammation of the tendons often leads to contractures of the fingers and Carpal Tunnel Syndrome. Onset of Eosinophilic Fasciitis has, in some cases, been related to the ingestion of the dietary supplement tryptophan. Symptoms most commonly follow strenuous physical activity. (For more information on this disorder, choose "Eosinophilic Fasciitis" as your search term in the Rare Disease Database.)

Treatment of Eosinophilic Myalgia consists of high doses of glucocorticoids (Hydrocortisone) to reduce the amount of circulating eosinophils. This treatment, however, does not usually improve the other symptoms.

Research on Eosinophilic Myalgia is ongoing. For more information about investigational therapies contact the Centers for Disease Control listed below.

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EOSINOPHILIC MYOPATHIC SYNDROMES. M. C. Pickering et al., Current Opin Rheumatol. (Nov 1998, 10 (6)). Pp. 504-10.

NEUROLOGIC, MR IMAGING AND MR SPECTROSCOPIC FINDINGS IN EOSINOPHILIA MYALGIA SYNDROME. L. J. Haseler et al., AJNR Am J Neuroradiol. (Oct 1998, 19 (9)). Pp. 1687-94.

PAIN, FATIGUE, AND SLEEP IN EOSINOPHILIA-MYALGIA SYNDROME: RELATIONSHIP TO NEUROPSYCHOLOGICAL PERFORMANCE. D. A. Pollina et al., J Neuropsychiatry Clin Neurosci. (Summer 1998, 10 (3)). Pp. 338-42.

STRUCTURAL CHARACTERIZATION OF CONTAMINANTS FOUND IN COMMERCIAL PREPARATIONS OF MELATONIN: SIMILARITIES TO CASE-RELATED COMPOUNDS FROM L-TRYPTOPHAN ASSOCIATED WITH EOSINOPHILIA-MYALGIA SYNDROME. B. L. Williamson et al., Chem Res Toxicol. (Mar 1998, 11 (3)). Pp. 234-40.

ASSOCIATION OF THE EOSINOPHILIA-MYALGIA SYNDROME WITH THE INGESTION OF TRYPTOPHAN. P. A. Hertzman et al.; New Eng J Med (Mar 29 1990; 322(13)). Pp. 869-73.

SCLERODERMA, FASCIITIS, AND EOSINOPHILIA ASSOCIATED WITH THE INGESTION OF TRYPTOPHAN. R. M. Silver et al.; New Eng J Med (Mar 29 1990; 322(13)). Pp. 874-81.

TRYPTOPHAN-INDUCED EOSINOPHILIA-MYALGIA SYNDROME. T. A. Medsger Jr.; New Eng J Med (Mar 29 1990; 322(13)). Pp. 926-28.