A search across likely websites:
CDC:
https://www.cdc.gov/me-cfs/index.html
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a serious, long-term illness that affects many body systems. People with ME/CFS are often not able to do their usual activities. At times, ME/CFS may confine them to bed. People with ME/CFS have severe fatigue and sleep problems. ME/CFS may get worse after people with the illness try to do as much as they want or need to do. This symptom is known as post-exertional malaise (PEM). Other symptoms can include problems with thinking and concentrating, pain, and dizziness.
https://www.cdc.gov/me-cfs/healthcare-providers/index.html
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex, chronic, debilitating disease with systemic effects. ME/CFS is characterized by reduced ability to perform pre-illness activities that lasts for more than 6 months and is accompanied by profound fatigue, which is not improved by rest. A hallmark of ME/CFS is that symptoms can worsen after physical, mental, or emotional effort, a manifestation known as post-exertional malaise (PEM). Patients with ME/CFS also have unrefreshing sleep. Other common manifestations are orthostatic intolerance, cognitive impairment, and pain. As can be observed in people with other long-term chronic illnesses, secondary psychological symptoms such as depression and anxiety may also be present in some patients with ME/CFS.
https://www.cdc.gov/me-cfs/healthca...clinical-course/etiology-pathophysiology.html
ME/CFS is a biological illness, not a psychologic disorder. Patients with ME/CFS are neither malingering nor seeking secondary gain. These patients have multiple pathophysiological changes that affect multiple systems. It is not known whether these changes occur prior to the onset of the illness or as its consequence. These changes include:
- Immune system abnormalities – some people with ME/CFS have impaired natural killer cell function and/or T cell function, chronic higher production of inflammatory cytokines, and in some cases slight increase in some autoantibodies (rheumatic factor, anti-thyroid antibodies, anti-gliadin, anti-smooth muscle antibodies, and cold agglutinins).
- Cellular metabolism abnormalities – some people with ME/CFS also appear to have impaired ability to produce energy from the usual “fuel” that cells use to produce energy: oxygen, glucose, fatty acids, and amino acids. Exercise studies in adults have revealed impaired oxygen consumption and activation of anaerobic metabolic pathways in the early stages of exercise.
- Neuroendocrine disturbances – some people with ME/CFS report physical or emotional stress before they become ill, which can lead to dysregulation of the hypothalamic-pituitary-adrenal axis (HPA axis). Some patients with ME/CFS have flattened diurnal cortisol profiles compared to healthy people, but their cortisol levels are still within the normal range.
- Blood pressure or heart rate regulation abnormalities – some people with ME/CFS, particularly adolescents, experience symptoms of orthostatic intolerance. Patients with orthostatic intolerance develop a worsening of symptoms with quiet upright posture and improvement (though not necessarily full resolution) of symptoms with recumbency. Two common forms of orthostatic intolerance experienced by patients with ME/CFS are:
Neurally-mediated hypotension (NMH): an abnormality in the regulation of blood pressure during upright posture. NMH is sometimes also referred to as neurocardiogenic syncope, vasodepressor syncope, vaso-vagal syncope, “the fainting reflex”, and delayed orthostatic hypotension.
Postural orthostatic tachycardia syndrome (POTS): an abnormality in the regulation of heart rate in which a change from lying to standing causes an abnormal increase in heart rate; the heart is usually structurally normal.
Emerge Australia:
https://www.emerge.org.au/what-is-mecfs
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex and disabling disease that affects many parts of the body, including the brain and muscles, as well as the digestive, immune and cardiac systems, among others. ME is classified as a neurological disorder by the World Health Organization.
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While there are currently no diagnostic biomarkers or tests for ME/CFS, there are many biological abnormalities that researchers have found in people living with the condition. These include an abnormal physiological response to exercise, altered immune function, changes in the bacteria in the gut, and impaired energy production.
Open Medicine Foundatin:
https://www.omf.ngo/what-is-mecfs/
Myalgic Encephalomyelitis or Chronic Fatigue Syndrome (ME / CFS) is a life-altering and complex multi-system disease that can present as an array of different symptoms that may change over time and differ from patient to patient. The most common symptoms of ME/CFS are post-exertional malaise, unrefreshing sleep, profound fatigue, cognitive impairment, orthostatic intolerance, and pain.
NZ sites:
https://www.healthinfo.org.nz/index.htm?Chronic-fatigue-syndrome-CFS.htm
ME/CFS (myalgic encephalomyelitis/chronic fatigue syndrome) is a debilitating, long-term illness that affects multiple systems of the body.
https://anzmes.org.nz/what-is-me/
ME/CFS is characterised by incapacitating fatigue, (experienced as profound exhaustion), problems with concentration and short-term memory, non-refreshing sleep and inability to exercise.
https://m.e.awareness.nz/what-is-me
ME is a debilitating, chronic, multi-system disease that affects the neurological, immune, endocrine, and energy metabolism systems.
https://mecfscanterbury.nz/#/mecfs
ME/CFS is a serious long-term illness. It affects people of all ages, ethnicities and both male and female. Overseas studies suggest the prevalence of ME/CFS is 4 in 1000 people, implying that there are 20,000 people affected in NZ.
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Researchers are finding issues with energy production, blood circulation and oxygen use.
US MECFS Clinician Coalition
https://mecfscliniciancoalition.org/about-mecfs/
Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic, complex, debilitating, multi-system illness...
ME-Pedia
https://me-pedia.org/wiki/Portal:Myalgic_Encephalomyelitis
Myalgic encephalomyelitis (ME) is a chronic, inflammatory, physically and neurologically disabling immune mediated disease that presents with symptoms involving multiple bodily systems. It is frequently triggered by a viral infection or a flu-like illness.[1] ME presents with symptoms in the central nervous system (CNS), autonomic nervous system (ANS), immune system, cardiovascular system, endocrine system, digestive system, and musculoskeletal system.[2][3] It is classified by the World Health Organization (WHO) as a neurological disease in 1969.[4]
https://me-pedia.org/wiki/Immune_system
Myalgic encephalomyelitis (ME) is a complex multi-systemic disorder which causes
neurological impairments,
energy metabolism/
ion transport dysfunction, and immune,
gastrointestinal and/or genitourinary symptoms.
[6] The
Centers for Disease Control and Prevention (CDC) notes that
ME/CFS impacts multiple body systems. These include the immune system,
cellular metabolism abnormalities,
neuroendocrine disturbances, and
b