Encephalomyelitis [Disease/Finding] Muscular Diseases [Disease/Finding] Fatigue Syndrome, Chronic [Disease/Finding] Postviral Fatigue Syndrome Fatigue Syndrome, Postviral N0000003304 51771007 Chronic Fatigue Syndrome A syndrome characterized by persistent or recurrent fatigue, diffuse musculoskeletal pain, sleep disturbances, and subjective cognitive impairment of 6 months duration or longer. Symptoms are not caused by ongoing exertion; are not relieved by rest; and result in a substantial reduction of previous levels of occupational, educational, social, or personal activities. Minor alterations of immune, neuroendocrine, and autonomic function may be associated with this syndrome. There is also considerable overlap between this condition and FIBROMYALGIA. (From Semin Neurol 1998;18(2):237-42; Ann Intern Med 1994 Dec 15;121(12): 953-9) D015673 Royal Free Disease Myalgic Encephalomyelitis Infectious Mononucleosis-Like Syndrome, Chronic Chronic Fatigue and Immune Dysfunction Syndrome Chronic Fatigue-Fibromyalgia Syndrome 52702003 1024042 C6786 Encephalomyelitis, Myalgic C0015674 Chronic Fatigue Disorder Fatigue Syndrome, Chronic M0024027 Fatigue Syndrome, Chronic