Chronic fatigue syndrome

A debilitating and complex disorder characterized by profound fatigue of six months or longer duration that is not improved by bed rest and that may be worsened by physical or mental activity. Persons with chronic fatigue syndrome (CFS) most often function at a substantially lower level of activity than they were capable of before the onset of illness. In addition to these key defining characteristics, patients report various nonspecific symptoms, including weakness, muscle pain, impaired memory and/or mental concentration, insomnia and post-exertional fatigue lasting more than 24 hours. In some cases, CFS can persist for years. The cause or causes of CFS have not been identified and no specific diagnostic tests are available. Moreover, since many illnesses have incapacitating fatigue as a symptom, care must be taken to exclude other known and often treatable conditions before a diagnosis of CFS is made. Known also as Chronic Fatigue and Immune Dysfunction Syndrome (CFIDS) and as Myalgic Encephalomyelitis (ME), there has been some debate over the existence and causes of this

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chronic fatigue syndrome n a disorder of uncertain cause that is characterized by persistent profound fatigue usu. accompanied by impairment in short-term memory or concentration, sore throat, tender lymph nodes, muscle or joint pain, and headache unrelated to any preexisting medical condition and that typically has an onset at about 30 years of age abbr. CFS called also myalgic encephalomyelitis

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persistent debilitating fatigue lasting longer than six months, with other known medical conditions having been ruled out by clinical diagnosis, accompanied by at least four of the following: significantly impaired short-term memory or concentration, muscle weakness, pain in multiple joints without swelling or redness, sore throat, tender lymph nodes, headaches, unrefreshing sleep, and malaise that lasts more than 24 hours following exertion. The cause is unknown and may be multifactorial; immune dysfunction has been suggested, and viral infection may be associated with it, although no causal relationship has been demonstrated. A number of names have been used for this syndrome, including Iceland disease, myalgic or benign myalgic encephalomyelitis, chronic Epstein-Barr virus infection, chronic mononucleosis, and epidemic neuromyasthenia.