Dr. William Reeves, M.D. Past Director of the CDC’s CFS Research program
Not An Easy Process!
Diagnosing chronic fatigue syndrome (ME/CFS) is not always easy. Because no laboratory tests are diagnostic for it diagnosing chronic fatigue syndrome (ME/CFS) involves having a physician examine your symptoms and excluding other diseases that could cause them. Your physician will take your personal history, probably asking questions such as:
- When did your fatigue start?
- How have your energy and activity levels been affected?
- Are your symptoms worse after you exercise?
- Do you have any problems with sleep?
- Do you have any problems with memory or concentration?
- Do you have any pain?
- What prescription or over the counter medications are you taking?
- Do you use drugs or drink alcohol?
- Have you been under increased stress lately?
Ruling Out Other Diseases
Because many CFS symptoms are fairly general a key part of a diagnosis involves ruling out other diseases that could cause them such as mononucleosis, multiple sclerosis, chronic Lyme disease, sleep disorders, severe obesity and reactions to medications. Physicians may use the criteria below to determine if you have it.
- Dig Deeper! Check out I’m Fatigued – Do I have chronic fatigue syndrome (ME/CFS)?
The 1994 International (“Fukuda”) Definition For Chronic Fatigue Syndrome
The Fukuda definition was created for researchers and physicians. Although widely recognized as inadequate the Fukuda definition is nevertheless the most widely used definition of this disease. (See the Canadian Consensus Definition below for an alternative definition designed for physicians). According to the Fukuda definition a person is considered to have ME/CFS if they have:
Chronic Fatigue: unexplained, persistent or relapsing chronic fatigue that is not substantially alleviated by rest, and results in substantial reductions in levels of occupational, educational, social, or personal activities; and
A Certain Set of Symptoms: four or more of the following symptoms for 6 or more consecutive months
- self-reported impairment in short-term memory or concentration
- post-exertional malaise (extreme, prolonged exhaustion and exacerbation of symptoms following physical or mental exertion)
- unrefreshing sleep
- muscle pain
- multi-joint pain without joint swelling or redness
- sore throat
- tender neck lymph nodes
- headaches of a new type, pattern, or severity
A Detailed Medical History: The CDC recommends physicians give potential CFS patients a thorough physical examination and mental screening including the following tests :
Laboratory Tests: urinalysis, total protein, glucose, C-reactive protein, phosphorous, electrolytes, complete blood count (CBC) with leukocyte differential, alkaline phosphatase (ALP), creatinine, blood urea nitrogen (BUN), albumin, ANA and rheumatoid factor, globulin, calcium alanine aminotransferase (ALT) or aspartate transaminase serum (AST), thyroid function tests (TSH and Free T4).
Diagnostic Guidelines and Laboratory Testing
- Dig Deeper: For more on the controversy on how to define chronic fatigue syndrome (ME/CFS) see ‘Hitting a Moving Target: Defining Chronic Fatigue Syndrome’
- Dig Deeper: The Canadian Consensus Criteria (CCC) – In contrast to the standard research definition of CFS, the Fukuda Definition, the CCC was written by ME/CFS professionals for physicians. A long document produced in 2003, it provides a more or less complete picture of the disease and is preferred by many doctors and patients. The CCC posits that postexertional malaise and cognitive problems are hallmarks of this disorder. In 2011 it was superseded with the publication of its updated version, the International Consensus Criteria (ICC).
- Dig Deeper: The Pediatric Definition – was developed under the auspices of International Association of chronic fatigue syndrome/ ME (IACFS/ME). It describes how the disease appears in children and is very similar to the Canadian Consensus Definition
- Dig Deeper: The ‘Empirical Definition‘ was developed in 2005 by a small group of researchers at the Centers for Disease Control. The Empirical Definition introduced emotional criteria, reduced the criteria for fatigue and created an algorithm based on standardized testing physicians and researchers could use to identify chronic fatigue syndrome patients. This definition resulted in greatly increased prevalence rates and has been much criticized ; it has not been adopted by either physicians or researchers.
- Dig Deeper: The International Consensus Criteria (2011) – is an updated version of the Canadian Consensus Criteria