The Hummingbirds' Foundation for M.E. (HFME)

M.E. is primarily neurological, but also involves cognitive, cardiac, cardiovascular, immunological, endocrinological, metabolic, respiratory, hormonal, gastrointestinal and musculo-skeletal dysfunctions and damage. M.E. affects all vital bodily systems and causes an inability to maintain bodily homeostasis. More than 64 individual symptoms of M.E. have been scientifically documented.

Myalgic encephalomyelitis is an acutely acquired disease with multi system involvement which is characterised by post encephalitic damage to the brain stem; a nerve centre through which many spinal nerve tracts connect with higher centres in the brain in order to control all vital bodily functions – this is always damaged in M.E.

Central nervous system (CNS) dysfunction, and in particular, inconsistent CNS function is undoubtedly both the chief cause of disability in M.E. and the most critical in the definition of the entire disease process.

This diffuse brain injury is initiated by a virus infection which targets the brain; M.E. represents a major attack on the CNS by the chronic effects of a viral infection (an enteroviral infection). M.E. is a loss of the ability of the CNS (the brain) to adequately receive, interpret, store and recover information which enables it to control vital body functions. It is a loss of normal internal homeostasis.

M.E. is primarily neurological, but because the brain controls all vital bodily functions virtually every bodily system can be affected by M.E. Again, although M.E. is primarily neurological it is also known that the vascular and cardiac dysfunctions seen in M.E. are also the cause of many of the symptoms and much of the disability associated with M.E. – and that the well-documented mitochondrial abnormalities present in M.E. significantly contribute to both of these pathologies. There is also multi-system involvement of cardiac and skeletal muscle, liver, lymphoid and endocrine organs in M.E. Some individuals also have damage to skeletal and heart muscle.

Thus M.E. symptoms are manifested by virtually all bodily systems including: cognitive, cardiac, cardiovascular, immunological, endocrinological, respiratory, hormonal, gastrointestinal and musculo-skeletal dysfunctions and damage. M.E. is a distinct, recognisable disease entity with several unique features. Individual symptoms of M.E. include:

Sore throat, chills, sweats, low body temperature, low grade fever, lymphadenopathy, muscle weakness (or paralysis), muscle pain, muscle twitches or spasms, gelling of the joints, hypoglycaemia, hair loss, nausea, vomiting, vertigo, chest pain, cardiac arrhythmia, resting tachycardia, orthostatic tachycardia, orthostatic fainting or faintness, circulatory problems, opthalmoplegia, eye pain, photophobia, blurred vision, wavy visual field, and other visual and neurological disturbances, hyperacusis, tinnitus, alcohol intolerance, gastrointestinal and digestive disturbances, allergies and sensitivities to many previously well-tolerated foods, drug sensitivities, stroke-like episodes, nystagmus, difficulty swallowing, weight changes, paresthesias, polyneuropathy, proprioception difficulties, myoclonus, temporal lobe and other types of seizures, an inability to maintain consciousness for more than short periods at a time, confusion, disorientation, spatial disorientation, disequilibrium, breathing difficulties, emotional lability, sleep disorders; sleep paralysis, fragmented sleep, difficulty initiating sleep, lack of deep-stage sleep and/or a disrupted circadian rhythm. Neurocognitive dysfunction may include cognitive, motor and perceptual disturbances.

Cognitive dysfunction may be pronounced and may include; difficulty or an inability to speak (or understand speech), difficulty or an inability to read or write or to do basic mathematics, difficulty with simultaneous processing, poor concentration, difficulty with sequencing and problems with memory including; difficulty making new memories, difficulty recalling formed memories and difficulties with visual and verbal recall (eg. facial agnosia). There is often a marked loss in verbal and performance intelligence quotient (IQ) in M.E.

What characterises M.E. every bit as much as the individual symptoms however is the way in which people with M.E. respond to physical and cognitive activity, sensory input and orthostatic stress, and so on. The way the bodies of people with M.E. react to these activities/stimuli post-illness is unique in a number of ways. Along with a specific type of damage to the brain (the CNS) this characteristic is one of the defining features of the illness which must be present for a correct diagnosis of M.E. to be made.

The main characteristics of the pattern of symptom exacerbations, relapses and disease progression (and so on) in M.E. include:

1. People with M.E. are unable to maintain their pre-illness activity levels. This is an acute (sudden) change. M.E. patients can only achieve 50%, or less, of their pre-illness activity levels post-M.E.
2. People with M.E. are limited in how physically active they can be but they are also limited in similar way with; cognitive exertion, sensory input and orthostatic stress.
3. When a person with M.E. is active beyond their individual (physical, cognitive, sensory or orthostatic) limits this causes a worsening of various neurological, cognitive, cardiac, cardiovascular, immunological, endocrinological, respiratory, hormonal, muscular, gastrointestinal and other symptoms.
4. The level of physical activity, cognitive exertion, sensory input or orthostatic stress needed to cause a significant or severe worsening of symptoms varies from patient to patient, but is often trivial compared to a patient’s pre-illness tolerances and abilities.
5. The severity of M.E. waxes and wanes throughout the hour/day/week and month.
6. The worsening of the illness caused by overexertion often does not peak until 24 - 72 hours (or more) later.
7. The effects of overexertion can accumulate over longer periods of time and lead to disease progression, or death.
8. The activity limits of M.E. are not short term: a gradual (or sudden) increase in activity levels beyond a patient’s individual limits can only cause relapse, disease progression or death in patients with M.E.
9. The symptoms of M.E. do not resolve with rest. The symptoms and disability of M.E. are not just caused by overexertion; there is also a base level of illness which can be quite severe even at rest.
10. Repeated overexertion can harm the patient’s chances for future improvement in M.E. M.E. patients who are able to avoid overexertion have repeatedly been shown to have the most positive long-term prognosis.
11. Not every M.E. sufferer has ‘safe’ activity limits within which they will not exacerbate their illness; this is not the case for the very severely affected.

M.E. is similar in a number of significant ways to illnesses such as multiple sclerosis, Lupus and Polio. 25% of M.E. sufferers are severely affected and housebound and/or bedbound. In some cases Myalgic Encephalomyelitis can also be progressive, or fatal.

M.E. is an infectious neurological illness of extraordinarily incapacitating dimensions that affects virtually every bodily system.

Because of the vast amount of inaccurate information being propagated about Myalgic Encephalomyelitis by various vested interest groups (helped immeasurably by the creation of the bogus disease category of ‘CFS’ as well as a number of vague and misleading umbrella terms such as ‘ME/CFS’ ‘CFS/ME’ ‘CFIDS’ and Myalgic ‘Encephalopathy’ etc.) it is important to explain briefly what are the myths about M.E., and the symptoms of M.E.

M.E. is not synonymous with being tired all the time. If a person is fatigued for an extended period of time this does not mean they are having a ‘bout’ of M.E. To suggest such a thing is no less absurd than to say that prolonged fatigue means a person is having a ‘bout’ of multiple sclerosis or Parkinson’s disease. Fatigue is a symptom of many different illnesses – but it is not a defining symptom of M.E., or an essential symptom of M.E. Some patients with M.E. may suffer with fatigue as a minor symptom, but many will not.

There are a number of post-viral fatigue states or fatigue syndromes which may follow common infections such as mononucleosis/glandular fever, hepatitis, Q fever, Ross river virus and so on. M.E. is an entirely different condition to these self-limiting fatigue syndromes however, the science is very clear on this point. M.E. is also not the same condition as Lyme disease, athletes over-training syndrome, burnout, depression, somatisation disorder, candida, multiple chemical sensitivity syndrome or Fibromyalgia, or indeed any other illness.

What defines M.E. is not ‘chronic fatigue’ but a specific type of damage to the brain. M.E. is an infectious neurological illness of extraordinarily incapacitating dimensions that affects virtually every bodily system – not a problem of unexplained ‘fatigue' or exhaustion.

For more information on this topic please see: The comprehensive M.E. symptom list and  What is Myalgic Encephalomyelitis? 

Many M.E. experts (and M.E. sufferers) have spoken out about against ‘fatigue’ being the defining features of M.E., see: M.E. is not defined by 'fatigue' and also the Quotes section for more information plus What it feels like to have Myalgic Encephalomyelitis: A personal M.E. symptom list and description of M.E.

The Fatigue Schmatigue paper explains how the fraudulent 'fatigue' construct came into being and how the M.E. community can and MUST play an active part in debunking this myth. This paper is aimed not at the public but at M.E. sufferers and other members of the M.E. community and is highly recommended.

It should not be assumed that because one may have some of the symptoms on the list that one necessarily has M.E. – many of them are common in a variety of other disorders and it is the pattern of symptoms which enables a M.E. diagnosis to be made, as well as the presence of a number of core characteristics and symptoms which are always present in the illness, and without which a diagnosis of M.E. should never be made. (For example, damage to the brain, the CNS, which is visible on brain scans, and so on.)

Even having a large number or percentage of the symptoms on this list does NOT necessarily mean a M.E. diagnosis is likely or even possible. M.E. cannot be accurately diagnosed merely on the presence of a certain percentage of possible M.E. symptoms. Those with Lyme disease may see many of their symptoms listed in M.S. or M.E. symptom lists, but this does not mean that Lyme disease is the same as M.S. or M.E. The same is true of many different diseases. Many diseases share a few symptoms, but what is important is the very different causes of these symptoms and the very different pathology and response to treatment seen in each of these patient groups.

None of these patient groups has the same cause of symptoms as seen in M.E. as none of these patient groups share the pathology of M.E. (For example, most of the symptoms of M.E. are caused by cardiac insufficiency and the associated reduced circulating blood volume of up to 50%. This can be so severe as to lead to death in M.E., in some cases. Yet this problem of cardiac insufficiency and reduced circulating blood volume simply does NOT OCCUR in these non-M.E. diseases.)

M.E. patients can be separated very easily and clearly from those with Lyme disease, various post-viral fatigue syndromes, candida, Bechet's disease, vitamin deficiencies, depression and other mental disease and so on when the onset of the disease is taken into consideration (unlike most of these diseases, the onset of M.E. is always sudden or acute) and when an evaluation of the core and unique symptoms of M.E. is done along with some of the tests used to confirm a M.E. diagnosis. M.E. should never be diagnosed based on a superficial analysis of non-core M.E. symptomatology. See: Testing for M.E. for more information on the diagnosis of M.E.