| Chronic fatigue syndrome (CFS), also known as | | | | Department of Health and Social Services and the |
| myalgic encephalomyelitis (ME), post-viral fatigue | | | | British Medical Association officially recognized it as |
| syndrome (PVFS), and various other names, is a | | | | a legitimate and potentially distressing disorder. |
| syndrome (or group of syndromes) of unknown | | | | Opponents of the term ME maintain there is no |
| and possibly multiple etiologies, affecting the | | | | inflammation, although there are cases of CFS |
| central nervous system (CNS), immune, and | | | | that present inflammation (see Sophia Mirza). |
| many other systems and organs. There is no | | | | United Kingdom and Canadian researchers and |
| simple diagnostic test; CFS is a diagnosis of | | | | patients generally use this term in preference to |
| exclusion, although recent research indicates | | | | CFS. |
| biological hallmarks of the syndrome, and a | | | | Chronic fatigue syndrome (CFS); this name was |
| diagnostic test is predicted soon. Most definitions | | | | introduced in 1988 by a group of United States |
| (other than the 1991 UK Oxford criteria[1]) require | | | | researchers based at the Centers for Disease |
| a number of features, the most common being | | | | Control and Prevention, and is used increasingly |
| severe mental and physical exhaustion or | | | | over other designations, particularly in the United |
| depletion which is "unrelieved by rest" (according | | | | States. |
| to the 1994 Fukuda definition),[2] and is often | | | | Chronic fatigue immune dysfunction syndrome |
| worsened by even trivial exertion (controversially, | | | | (CFIDS); many people, many patients and |
| the Oxford and Fukuda criteria require this to be | | | | advocacy groups in the USA use the term CFIDS |
| optional only). CFS occurs more often, but not | | | | (pronounced [See-Fids]), originally an acronym for |
| exclusively, in women, possibly due to | | | | the above or "Chronic Fatigue & Immune |
| immunological factors (women are overall more | | | | Dysfunction Syndrome". This term was introduced |
| susceptible to similar disorders). CFS is most easily | | | | by patients current with the biomedical research in |
| diagnosed when formerly active adults become ill, | | | | an attempt to reduce the psychiatric stigma |
| but it has been reported in persons of all ages, | | | | attached to "chronic fatigue", as well as the public |
| including young children and particularly teenagers. | | | | perception of CFS as a psychiatric syndrome. The |
| Patients with this diagnosis commonly report | | | | term also calls attention to the immune |
| many other symptoms which are far more | | | | dysfunction in patients for which evidence has |
| wide-ranging than these research diagnostic | | | | been steadily growing since the illness was first |
| criteria, including: pain, muscle weakness, loss of | | | | identified, and which now appears to be an integral |
| brain function, hypersensitivity, orthostatic | | | | part of this illness. |
| intolerance, digestive disturbances, depression, | | | | Post-viral [fatigue] syndrome (PVS or PVFS); this |
| immune system weakness, and cardiac and | | | | is a related disorder. According to original ME |
| respiratory problems. These symptoms, like the | | | | researcher Dr. Melvin Ramsay, "The crucial |
| syndrome's hallmark 'fatigue', range from mild to | | | | differentiation between ME and other forms of |
| life-threateningly severe. Some cases resolve or | | | | post-viral fatigue syndrome lies in the striking |
| improve over time, and where available, | | | | variability of the symptoms not only in the course |
| treatments bring a degree of improvement to | | | | of a day but often within the hour. This variability |
| many others. Most diagnostic criteria insist that | | | | of the intensity of the symptoms is not found in |
| the symptoms must be present for at least six | | | | post-viral fatigue states" (Ramsay 1989). |
| months, and all insist on there being no other | | | | However, other researchers and advocates argue |
| cause for the fatigue: i.e. the fatigue must be | | | | that other post-viral syndromes (such as |
| idiopathic, not caused by conditions such as | | | | post-polio syndrome) do show similar variability, |
| radiation treatment for cancer, or diabetes. CFS | | | | and point to the striking similarity between |
| remains a controversial diagnosis, and even its | | | | post-viral fatigue syndrome and CFS symptoms, |
| terminology and classification are controversial. | | | | noting that many CFS cases are triggered by a |
| Recently, genetics and stress have been found to | | | | viral illness. |
| be factors in the development of CFS. | | | | Chronic Epstein-Barr virus (CEBV) or Chronic |
| Originally studied in the late 1930s as an | | | | Mononucleosis; the term CEBV was introduced by |
| immunological neurological disorder under the | | | | virologists Dr. Stephen Straus and Dr. Jim Jones in |
| medical term "myalgic encephalomyelitis" (ME), | | | | the United States. The Epstein-Barr virus, a |
| CFS has been classified by the World Health | | | | neurotropic virus that more commonly causes |
| Organization (WHO) as a disease of the central | | | | infectious mononucleosis, was thought by Straus |
| nervous system since 1969. In 1992 and early | | | | and Jones to be the cause of CFS. Subsequent |
| 1993 the terms "post-viral fatigue syndrome" | | | | discovery of the closely related human |
| (PVFS) and "chronic fatigue syndrome" (CFS) | | | | herpesvirus 6 shifted the direction of biomedical |
| were added to ME under the exclusive ICD-10 | | | | studies, although a vastly expanded and |
| designation of G93.3. | | | | substantial body of published research continues |
| Lacking a diagnostic test of any kind, CFS has | | | | to show active viral infection or reinfection of CFS |
| historically been mis-diagnosed, for example in | | | | patients by these two viruses. These viruses are |
| patients presenting CFS symptoms with similar | | | | also found in healthy controls, lying dormant. |
| biological conditions or infections (such as Lyme or | | | | Low Natural Killer cell disease; this name is used |
| Epstein-Barr) (the latter of which is often the | | | | widely in Japan. It reflects research showing a |
| cause of glandular fever, or infectious | | | | reduction in the number of natural killer cells in |
| mononucleosis), or psychological conditions (ranging | | | | many CFS patients. More significantly, the activity |
| from depression to hypochondria). A lack of | | | | of the remaining natural killer cells is reduced, |
| information and awareness has led to many | | | | often by as much as two thirds. |
| patients being stigmatized as hypochondriac or | | | | Yuppie Flu; this was a factually inaccurate |
| lazy. The Centers for Disease Control & | | | | nickname for CFS, first published in a November |
| Prevention (CDC) have now recognized CFS as a | | | | 1990 Newsweek article. It reflects an assumption |
| serious illness and have recently launched a | | | | that CFS mainly affects the affluent ("yuppies"), |
| campaign to raise public and medical awareness | | | | and implies that it is a form of malingering or |
| about it. | | | | burnout. CFS, however, affects people of all |
| There are a number of different terms which | | | | races, genders, and social standings, and this |
| have been identified at various times with this | | | | nickname is inaccurate and considered offensive |
| disorder. | | | | by patients. It is likely that this article contributed |
| Myalgic encephalomyelitis (pronounced [my-al'jik | | | | to the damaging public (and even medical) |
| en-sef'a-lo-my'e-ly'tis]) or M.E, "inflammation of the | | | | perception of CFS as a psychiatric or even |
| brain and spinal cord with muscle pain", as a | | | | psychosomatic condition. |
| disease entity has been recognized and described | | | | Uncommonly used terms include Akureyri Disease, |
| in the medical literature since 1938, with the | | | | Iceland disease (in Iceland), Royal Free disease |
| seminal paper being that by Wallis in 1957; Sir | | | | (after the location of an outbreak), atypical |
| Donald Acheson's (a former Chief Medical Officer) | | | | poliomyelitis, epidemic vasculitis, raphe nucleus |
| major review of ME was published in 1959;[3] in | | | | encephalopathy, and Tapanui flu (after the New |
| 1962 the distinguished neurologist Lord Brain | | | | Zealand town Tapanui where the first doctor in |
| included ME in his textbook of neurology, and in | | | | the country to investigate the disease, Dr Peter |
| 1978 the Royal Society of Medicine accepted ME | | | | Snow, lived). |
| as a distinct clinical entity. In 1988 both the UK | | | | |