The Difference Between CFS and ME
Myalgic encephalomyelitis (ME) is a multi-system disease adversely affecting the
cellular mitochondria and the heart, brain, neuroendocrine, immune, and circulatory
systems. ME was first described in the 1950's following the recognition of many cases
around the world, including a number of cases at the Royal Free Hospital in England. Many
different viruses, bacteria, or toxins in combination with genetic factors may be
involved in the etiology of the disease, which usually begins in childhood or early
adulthood with an acute infection.
Сhronic fatigue syndrome (CFS) is the most common name given to a variably
debilitating disorder or disorders generally defined by persistent fatigue unrelated
to exertion, not substantially relieved by rest and accompanied by the presence of
other specific symptoms for a minimum of six months.
The U.S. Centers for Disease Control and Prevention (CDC) first defined CFS in 1988. This
definition was later rolled over to a more complex 1994 definition, which was
subsequently corrected and corrected again. These CFS definitions have multiplied beyond
the two CDC definitions and now include the Oxford Dictionary definitions of CFS (there
are two of them), the Australian definitions, and the more recent Canadian definition
that talks of ME/CFS as though they were the same illness. They are not. ME has a
clearly defined disease process while CFS by definition has always been a syndrome.
Diagnostic Criteria For CFS
Your clinician should consider a diagnosis of CFS if these two criteria are met:
Unexplained, persistent fatigue that's not due to ongoing
exertion, isn't substantially relieved by rest, is of new onset (not lifelong) and
results in a significant reduction in previous levels of activity.
Four or more of the following symptoms are present for six months
- Impaired memory or concentration
- Postexertional malaise (extreme, prolonged exhaustion and sickness following physical
or mental activity)
- Un refreshing sleep
- Muscle pain
- Multi joint pain without swelling or redness
- Headaches of a new type or severity
- Sore throat that's frequent or recurring
- Tender cervical or axillary lymph nodes
In addition, a number of minor symptoms may also appear:
- Poor sleep
- Brain fog
- Increased thirst
- Bowel disorders
- Recurrent infections
- Exhaustion after minimal exertion
Chronic fatigue syndrome can resemble many other illnesses, including
mononucleosis, chronic lyme disease, lupus, multiple sclerosis,
primary sleep disorders, severe obesity and major depressive
disorders. Medications can also cause side effects that mimic the symptoms of CFS/ME.
Because CFS can resemble many other disorders, it's important not to self-diagnose
CFS. It's not uncommon for people to mistakenly assume they have chronic fatigue
syndrome when they have another illness that needs to be treated. A CFS diagnosis
can be made only after other conditions have been excluded.
The 'London' Criteria for ME - Version 2
These three criteria must all be present for a diagnosis of M.E./PVFS to be made. If
any of these are not present the volunteer research subject should not be used for
the purpose of research into M.E./PVFS and an alternative diagnosis should be
Exercise-induced fatigue precipitated by trivially small exertion, physical or
mental, relative to the patient's previous exercise tolerance.
Impairment of short-term memory and loss of powers of concentration, usually
coupled with other neurological and psychological disturbances such as emotional
lability, nominal dysphasia, disturbed sleep patterns, dysequilibrium or tinnitus.
Fluctuation of symptoms, usually precipitated by either physical or mental
exercise (see b) above.
These symptoms should have been present for at least 6 months and should be ongoing.
The Nightingale Definition of ME
Primary ME is a chronic disabling, acute onset biphasic epidemic or endemic (biphasic)
infectious disease process affecting both children and adults. There are both central
and peripheral aspects to this illness.
The Central Nervous System (CNS) symptoms, as well as the clinical and technological
abnormalities, are caused by a diffuse and measurable injury to the vascular system
of the Central Nervous System. These changes in the organization of the CNS are caused
by a combined infectious and immunological injury and their resulting effect on CNS
metabolism and control mechanisms. Much of the variability observed in an ME
patient's illness is due to the degree and extent of the CNS injury and the ability
of the patient to recover from these injuries.
A significant number of the initial and long-term peripheral or body symptoms, as
well as clinical and technological body abnormalities in the ME patient, are caused
by variable changes in the peripheral and CNS vascular system. The vascular system
is perhaps the largest of the body's organs and both its normal and patho
physiological functions are in direct relationship to CNS and peripheral vascular
health or injury, to CNS control mechanisms and to the difficulty of the peripheral
vascular system and organs to respond to CNS neuro-endocrine and other chemical and
neurological stimuli in a predictable homeostatic fashion.
When pain syndromes associated with ME occur, they are due to a combined injury of
(i) the posterior spinal cord and / or posterior root ganglia and appendages,
(ii) patho-physiological peripheral vascular changes, and (iii) CNS pain reception
The Canadian Clinical Case Definition for ME
1. POST-EXERTIONAL MALAISE AND FATIGUE:
There is a loss of physical and mental stamina,
rapid muscular and cognitive fatigability, post-exertional fatigue, malaise and/or pain,
and a tendency for other symptoms to worsen. A pathologically slow recovery period (it
takes more than 24 hours to recover). Symptoms exacerbated by stress of any kind.
Patient must have a marked degree of new onset, unexplained, persistent, or recurrent
physical and mental fatigue that substantially reduces activity level.
SLEEP DISORDER: Unrefreshing sleep or poor sleep quality; rhythm disturbance.
Arthralgia and/or myalgia without clinical evidence of inflammatory responses
of joint swelling or redness. Pain can be experienced in the muscles, joints, or neck
and is sometimes migratory in nature. Often, there are significant headaches of new
type, pattern, or severity.
4. NEUROLOGICAL/COGNITIVE MANIFESTATIONS:
Two or more of the following difficulties
should be present: confusion, impairment of concentration and short-term memory
consolidation, difficulty with information processing, categorizing, and word retrieval,
intermittent dyslexia, perceptual/sensory disturbances, disorientation, and ataxia.
There may be overload phenomena: informational, cognitive, and sensory overload - e.g.,
photophobia and hypersensitivity to noise - and/or emotional overload which may lead to
relapses and/or anxiety.
5. AT LEAST ONE SYMPTOM OUT OF TWO OF THE FOLLOWING CATEGORIES:
AUTONOMIC MANIFESTATIONS: Orthostatic Intolerance: e.g., neurally mediated
hypotension (NMH), postural orthostatic tachycardia syndrome (POTS), delayed postural
hypotension, vertigo, light-headedness, extreme pallor, intestinal or bladder
disturbances with or without irritable bowel syndrome (IBS) or bladder dysfunction,
palpitations with or without cardiac arrhythmia, vasomotor instability, and
NEUROENDOCRINE MANIFESTATIONS: loss of thermostatic stability, heat/cold
intolerance, anorexia or abnormal appetite, marked weight change, hypoglycemia, loss
of adaptability and tolerance for stress, worsening of symptoms with stress and slow
recovery, and emotional lability.
IMMUNE MANIFESTATIONS: tender lymph nodes, sore throat, flu-like symptoms,
general malaise, development of new allergies or changes in status of old ones, and
hypersensitivity to medications and/or chemicals.
The illness persists for at least 6 months. It usually has an acute onset, but
onset also may be gradual. Preliminary diagnosis may be possible earlier. The
disturbances generally form symptom clusters that are often unique to a particular
patient. The manifestations may fluctuate and change over time. Symptoms exacerbate
with exertion or stress.
What Are the Symptoms of ME and CFS?