Evaluation of ME/CFS

What to know

ME/CFS can be extremely difficult to diagnose as there is no diagnostic test and the symptoms are common in many other illnesses. Diagnosing ME/CFS requires many steps and different strategies. These include asking detailed questions about the patient's illness and lab tests to rule out other common fatiguing illnesses.

Female doctor examines the symptoms of a patient who enters the clinic using a medical device.

Evaluation Strategies

Evaluation of ME/CFS requires assessing the patient's symptoms, medical history, physical exam findings, recent laboratory test results, and clinical judgment.

As for any condition, healthcare providers typically determine the sequence and prioritization of laboratory testing based on individual patients' presentations.

The tests below are routinely used for patient evaluation by healthcare providers with clinical expertise in ME/CFS. The main goal is identifying and ruling out other illnesses. Not all of the tests listed below may be needed initially or concurrently:

  • Complete blood count with differential
  • Erythrocyte sedimentation rate (ESR)
  • Electrolytes
  • Fasting glucose
  • Renal function:
    • creatinine
    • blood urea nitrogen (BUN)
    • glomerular filtration rate
  • Calcium
  • Phosphate
  • Liver function:
    • bilirubin
    • alanine aminotransferase (ALT)
    • alkaline phosphatase (ALP)
    • aspartate aminotransferase (AST)
    • gamma-glutamyl transferase (GGT)
    • total protein
    • albumin/globulin ratio
  • C-reactive protein
  • Thyroid Function:
    • thyroid-stimulating hormone (TSH)
    • free thyroxine (free T4)
  • Iron studies to assess for both iron overload and deficiency:
    • serum iron
    • transferrin saturation
    • ferritin
  • Celiac disease screening
  • Urinalysis

Assessing lab results

Despite being substantially debilitated, most people with ME/CFS have routine laboratory test results that are within normal ranges. Further testing may be indicated to confirm other illnesses if suggested by an individual patient's history and/or physical findings.

For example, if autoimmune disease is suspected, the healthcare provider may order additional tests such as antinuclear antibodies. However, healthcare providers should be cautious of extensive testing without clinical suspicion because of the risk of false-positive tests.

If abnormal laboratory findings are present, further evaluation is warranted. For example, if anemia is identified, further studies are generally indicated to characterize and treat the anemia. These studies might include tests for deficiencies in B12 and folate. Anemia can also be a presenting symptom of celiac disease.

Some ME/CFS expert healthcare providers include vitamin level studies, including B12, folate, and vitamin D, in initial testing. For patients with cognitive impairment, assessment of B12 and folate can help identify underlying conditions.

Additional tests to consider

Additional tests such as imaging and physiological assessments may be needed to diagnose underlying illnesses. These tests might include:

  • Cultures or blood tests if an infection is suspected
  • MRI or other neuroimaging procedures
  • Sleep studies
  • Exercise testing (including VO2max)
  • Tilt table testing, often in consultation with a specialist.

Be aware that a patient can have ME/CFS and a co-existing condition that causes fatigue. They can also have other ME/CFS symptoms like blood pressure abnormalities. These co-existing conditions should be treated appropriately.

Extensive testing and frequent healthcare provider visits may exacerbate ME/CFS symptoms. So, follow-up visits should be scheduled thoughtfully. Some patients with ME/CFS may not look ill during office visits. Those with more severe symptoms might not always be able to keep all of their appointments.

Assessing impact on cognition

Tests can be useful to assess patients’ cognitive skills. ME/CFS may affect concentration, memory, and processing speed.

This additional testing can also be useful in identifying particular areas in which specific tools or strategies might help.

Assessments and strategic interventions may be particularly helpful to children and adolescents with ME/CFS. Academic attendance and performance are important for these patients, and their specific educational needs should be addressed.

  • Disclaimer: The content of this ME/CFS website is for informational purposes only and does not represent a federal guideline or recommendation for the treatment of ME/CFS. The information provided on this website is not intended to be a substitute for the medical judgment of the healthcare provider and does not indicate an exclusive course of action or treatment.