An expert committee from the Institute of Medicine (IOM) has proposed new diagnostic criteria for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) to facilitate timely diagnosis and care while improving knowledge among healthcare providers and patients, as well as changing the name of the disease. The recommendations appear in the IOM report Beyond Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Redefining an Illness.

The IOM expert committee was formed after The Department of Health and Human Services (HHS), the National Institutes of Health, the Agency for Healthcare Research and Quality, the Centers for Disease Control and Prevention, the Food and Drug Administration, and the Social Security Administration requested an examination of the evidence base for ME/CFS. After conducting a comprehensive literature review and assessing input from patient, advocacy, and research communities, the committee developed the following new diagnostic criteria in which it is required that the patient have the following three symptoms:

  • A substantial reduction or impairment in the ability to engage in pre-illness levels of occupational, educational, social, or personal activities, that persists for more than six months and is accompanied by fatigue, which is often profound, is of new or definite onset (not lifelong), is not the result of ongoing excessive exertion, and is not substantially alleviated by rest
  • Post-exertional malaise
  • Unrefreshing sleep

In addition, at least one of the two following manifestations is also required:

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With these symptoms, frequency and severity should be assessed and a ME/CFS diagnosis questioned if patients do not have these symptoms at least half of the time with moderate, substantial, or severe intensity.

The committee also recommended that physicians diagnose ME/CFS in children and adults if the new diagnostic criteria are met after a thorough review of the patient’s medical history, a physical examination, and a targeted workup to rule out other disorders and identify any other coexisting conditions. It is advised that a screening and diagnostic toolkit for use in a wide range of clinical settings be developed by HHS, along with a nationwide dissemination strategy.

Lastly, the committee stated that the term ME/CFS perpetuates misunderstanding of the illness and dismissive attitudes from healthcare providers and the public. As well, the term myalgic encephalomyelitis is inappropriate due to a lack of evidence for encephalomyelitis in ME/CFS patients and myalgia is not a core symptom of the disease. It is proposed that the name systemic exertion intolerance disease (SEID) better represents the adverse effect of exertion (physical, cognitive, or emotional) in many organ systems and aspects of patient lives.

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