The Chronic Fatigue Syndrome


CFS overview

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



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