The International Consensus Diagnostic Criteria for ME were published by the Journal of Internal Medicine in July 2011. They were written by a large group of ME specialists from a number of different countries. They make it clear that ME is an acquired neurological disease which effects the immune and endocrine systems among others.
The Criteria, including details and qualifications of the many specialists who worked on them, information about relevant research, and other medical references, can be found on the ME Association website. The MEA also link to a short version which lists all the Criteria in full but not the other details: this is easier to read and is helpful if you would like a printed version.
There is a brief summary below for those who are unable to read even the short version of the Criteria, or who are just looking for a quick overview: please note that this is not an alternative to the Criteria and should not be used for diagnostic purposes. If you reproduce this summary elsewhere, please ensure you include the links to the full Criteria.
Summary
A. Post-Exertional Neuro-Immune Exhaustion - compulsory for diagnosis of ME.
This follows both physical and mental activities, and results in a worsening of other symptoms. It may occur immediately or be a delayed reaction. The recovery period is prolonged. The patient will lack stamina and be able to do significantly less than they could prior to onset of illness.
B. Neurological Impairments - at least one symptom from three of the four categories.
1. Neurocognitive impairments, eg difficulty processing information, poor concentration, and short-term memory loss. These should become more pronounced with fatigue.
2. Pain, eg headaches, migraines, muscle and joint pains.
3. Sleep disturbance, eg insomnia, sleeping during the day and being awake at night, vivid dreams, and unrefreshing sleep.
4. Neuroensory, perceptual, and motor disturbances, eg sensitivity to light and noise, and muscle weakness and twitching.
C. Immune, Gastro-intestinal, and Genitourinary Impariments - at least one symptom from three of the five categories.
1. Flu-like symptoms, eg sore throat and tender lymph nodes, occuring or worsening following exercise.
2. Susceptibility to viral infections with prolonged recovery periods.
3. Gastro-intestinal symptoms, eg nausea, abdominal pain, and irritable bowel syndrome.
4. Genitourinary symptoms, eg urinary frequency or urgency.
5. Sensitivities to food, medications, odours, or chemicals.
D. Energy Production/Transportation Impairments - at least one symptom.
Cardiovascular symptoms, eg orthostatic intolerance, palpitations, arrythmias, and dizziness.
Respiratory symptoms, eg air hunger and laboured breathing.
Thermostatic problems, eg low temperature or sweating; intolerance of extremes of temperature.
The Criteria also make specific reference to ME in children and to atypical ME.
The International Consensus Diagnostic Criteria supersede the Canadian Consensus Criteria, the previous benchmark for diagnosis of ME, although these are still very informative and may still be used for reference.
A range of other criteria have been used in the past (and in some cases still are), but none are so accurate or comprehensive. In particular, criteria used to describe chronic fatigue syndrome are very limited in their scope, referring only to a small number of (often minor) ME symptoms.
