Canadian Clinical Working Case Definition of ME/CFS

I don’t understand why the United States does not acknowledge myalgic encephalomyelitis. The Merck Manual doesn’t even mention it and the symptoms and recommendations for chronic fatigue syndrome are not the same as for M.E. Canada, Australia and the UK seem to be light-years ahead in their acknowledgement of this disease, if not their treatment (but probably that, too).

The “Myalgic Encephalomyelitis/ Chronic Fatigue Syndrome: Clinical Working Case Definition, Diagnostic and Treatment Protocols” written in Canada by Dr. Bruce Carruthers et al. is excellent. It says, “As the CDC definition was primarily created to standardize research, it may not be appropriate to use for clinical diagnoses, a purpose for which it was never intended. There has been a growing demand within the medical community for a clinical case definition for ME/CFS for the benefit of the family physician and other treating clinicians. The CDC definition, by singling out severe, prolonged fatigue as the sole major (compulsory) criterion, de-emphasized the importance of other cardinal symptoms, including post-exertional malaise, pain, sleep disturbances, and cognitive dysfunction. This makes it more difficult for the clinician to distinguish the pathological fatigue of ME/CFS from ordinary fatigue or other fatiguing illnesses.” This makes me want to punch the CDC in the face. This is why my visit to what I thought was the Chronic Fatigue SYNDROME Clinic turned out to be just the Chronic Fatigue Clinic — for all fatigue. For people who don’t sleep, people who are depressed, people who are overweight and don’t exercise, people with other fatiguing diseases. Eat pizza because your blood pressure is low, eat turkey because you don’t sleep well, get massages because your muscles hurt. Idiotic advice. Thanks, I’ve been on the waiting list for months, feeling like I’m dying a slow, uninformed death and that’s the best you’ve got? I’m still irritated. Actually, I’m outraged. But I’ve bitched about that enough in other posts.

Let’s look at the Clinical Working Case Definition of ME/CFS from the article above:

1. Fatigue: The patient must have a significant degree of new onset, unexplained, persistent, or recurrent physical and mental fatigue that substantially reduces activity level. CHECK
2. Post-Exertional Malaise and/or Fatigue: There is an inappropriate loss of physical and mental stamina, rapid muscular and cognitive fatigability, post exertional malaise and/or fatigue and/or pain and a tendency for other associated symptoms within the patient’s cluster of symptoms to worsen. There is a pathologically slow recovery period–usually 24 hours or longer. CHECK
3. Sleep Dysfunction:* There is unrefreshed sleep or sleep quantity or rhythm disturbances such as reversed or chaotic diurnal sleep rhythms. CHECK
4. Pain:* There is a significant degree of myalgia. Pain can be experienced in the muscles and/or joints, and is often widespread and migratory in nature. CHECK Often there are significant headaches of new type, pattern or severity. CHECK
5. Neurological/Cognitive Manifestations: Two or more of the following difficulties should be present: confusion, impairment of concentration CHECK and short-term memory consolidation, disorientation, difficulty with information processing, categorizing and word retrieval, CHECK and perceptual and sensory disturbances–e.g., spatial instability and disorientation and inability to focus vision. CHECK Ataxia, muscle weakness and fasciculations are common. CHECK There may be overload phenomena: cognitive, sensory–e.g., photophobia CHECK and hypersensitivity to noise CHECK–and/or emotional overload, which may lead to “crash” periods and/or anxiety. CHECK
6. At Least One Symptom from Two of the Following Categories:
a. Autonomic Manifestations: orthostatic intolerance–neurally mediated hypotenstion (NMH), CHECK postural orthostatic tachycardia syndrome (POTS), CHECK delayed postural hypotension; light-headedness; CHECK extreme pallor; nausea and irritable bowel syndrome; CHECK urinary frequency CHECK and bladder dysfunction; palpitations with or without cardiac arrhythmias; CHECK exertional dyspnea. CHECK 
b. Neuroendocrine Manifestations: loss of thermostatic stability– subnormal body temperature and marked diurnal fluctuation, CHECK sweating episodes, CHECK recurrent feelings of feverishness CHECK and cold extremities; CHECK intolerance of extremes of heat and cold; CHECK marked weight change–anorexia or abnormal appetite; loss of adaptability and worsening of symptoms with stress. CHECK
c. Immune Manifestations: tender lymph nodes, recurrent sore throat, CHECK recurrent flu-like symptoms, CHECK general malaise, CHECK new sensitivities to food, CHECK medications CHECK and/or chemicals.
7. The illness persists for at least six months. CHECK It usually has a distinct onset,** CHECK although it may be gradual.
To be included, the symptoms must have begun or have been significantly altered after the onset of this illness. It is unlikely that a patient will suffer from all symptoms in criteria 5 and 6. The disturbances tend to form symptom clusters that may fluctuate and change over time. CHECK
*There is a small number of patients who have no pain or sleep dysfunction, but no other diagnosis fits except ME/CFS. A diagnosis of ME/CFS can be entertained when this group has an infectious illness type onset.
**Some patients have been unhealthy for other reasons prior to the onset of ME/CFS and lack detectable triggers at onset and/or have more gradual or insidious onset.

Exclusions: Exclude active disease processes that explain most of the major symptoms of fatigue, sleep disturbance, pain, and cognitive dysfunction. It is essential to exclude certain diseases, which would be tragic to miss: Addison’s disease, EXCLUDED Cushing’s Syndrome, EXCLUDED hypothyroidism, EXCLUDED hyperthyroidism, EXCLUDED iron deficiency, EXCLUDED other treatable forms of anemia, iron overload syndrome, diabetes mellitus, EXCLUDED and cancer. EXCLUDED It is also essential to exclude treatable sleep disorders such as upper airway resistance syndrome and obstructive or central sleep apnea; EXCLUDED rheumatological disorders such as rheumatoid arthritis, EXCLUDED lupus, EXCLUDED polymyositis ? and polymyalgia rheumatica; ? immune disorders such as AIDS; EXCLUDED neurological disorders such as multiple sclerosis (MS), ? Parkinsonism, myasthenia gravis ? and B12 deficiency; EXCLUDED infectious diseases such as tuberculosis, EXCLUDED chronic hepatitis, EXCLUDED Lyme disease, EXCLUDED etc.; primary psychiatric disorders EXCLUDED and substance abuse. EXCLUDED Exclusion of other diagnoses, which cannot be reasonably excluded by the patient’s history and physical examination, is achieved by laboratory testing and imaging. If a potentially confounding medical condition is under control, then the diagnosis of ME/CFS can be entertained if patients meet the criteria otherwise.

Co-Morbid Entities: Fibromyalgia Syndrome (FMS), CHECK Myofascial Pain Syndrome (MPS), Temporomandibular Joint Syndrome (TMJ), CHECK Irritable Bowel Syndrome (IBS), CHECK Interstitial Cystitis, Irritable Bladder Syndrome, Raynaud’s Phenomenon, CHECK Prolapsed Mitral Valve, Depression, CHECK Migraine, CHECK Allergies, CHECK Multiple Chemical Sensitivities (MCS), Hashimoto’s thyroiditis, CHECK Sicca Syndrome, etc. Such co-morbid entities may occur in the setting of ME/CFS. Others such as IBS may precede the development of ME/CFS by many years, but then become associated with it. The same holds true for migraines and depression. Their association is thus looser than between the symptoms within the syndrome. ME/CFS and FMS often closely connect and should be considered to be “overlap syndromes.”

Now, if that’s a fact, tell me: Am I lying?


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