Criteria - Canadian Guidelines contrasted to Oxfor

Worcestershire

M.E. Support Group

Website:

Chairman - Ian Logan (01886 888419)

Vice Chairman - Warwick Davis (01384 892442)

Criteria - Canadian Guidelines (contrasted to Oxford and Fukuda)

The complete 109-page article 'Myalgic Encephalomyelitis/CFS: Clinical Working Case Definition,

Diagnostic and Treatment Protocols', Journal of CFS, Vol. 11 (1) 2003, pp. 7-116, is available at

/documents/

This summary is paraphrased from Dr. Kenny van DeMeirleir's book 'CFS: A Biological Approach',

Feb. 2002, p.275. The Canadian Consensus Panel clinical case definition more accurately

represents the experience and manifestations of the disease than other current case definitions

ie Oxford or Fukuda.

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 pathalogically 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. [ME Society of America Editor's note: The ME Society

prefers to use 'delayed recovery of muscle function', weakness, and faintness rather than

'fatigue'. Further, we disagree that the muscle dysfunction is 'unexplained'] - (see their ME

Definitional Framework and researchers' medical explanations at the same link at top of page).

2.

Sleep Disorder: Unrefreshing sleep or poor sleep quality; rhythm disturbance.

3.

Pain: 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 and 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, categorising, and word retrieval, intermittent dyslexia,

perceptual/sensory disturbances, disorientation, and ataxia. There may be overload phenomena:

informational, cognitive and sensory overload (eg 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:

a. Autonomic Manifestations: Orthostatic Intolerance eg 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 respiratory irregularities.

b. 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.

c. Immune manifestations: Tender lymph nodes, sore throat, flu-like symptoms, general malise,

development of new allergies or changes in status of old ones, and hypersensitivity to

medications and/or chemicals.

6.

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 from

symptom clusters that are often unique to a particular patient. The manifestations may fluctuate

and change over time. Symptoms exacerbate with exertion or stress.

(Worcestershire M.E. Support Group’s Library)

October 2005

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