NICE Guideline > Suspecting ME/CFS

NICE logo.

Suspecting ME/CFS

1.2 Suspecting ME/CFS

1.2.1 Explain to people presenting with possible symptoms of ME/CFS that there currently is no diagnostic test for ME/CFS and it is recognised on clinical grounds alone.

1.2.2 Suspect ME/CFS if:

  • the person has had all of the persistent symptoms in box 2 for a minimum of 6 weeks in adults and 4 weeks in children and young people and
  • the person's ability to engage in occupational, educational, social or personal activities is significantly reduced from pre‑illness levels and
  • symptoms are not explained by another condition.

Box 2 Symptoms for suspecting ME/CFS

All of these symptoms should be present:

  • Debilitating fatigue that is:
    • worsened by activity,
    • is not caused by excessive cognitive, physical, emotional or social exertion, and,
    • is not significantly relieved by rest.
  • Post-exertional malaise after activity in which the worsening of symptoms:
    • is often delayed in onset by hours or days,
    • is disproportionate to the activity,
    • has a prolonged recovery time that may last hours, days, weeks or longer.
  • Unrefreshing sleep or sleep disturbance (or both), which may include:
    • feeling exhausted, feeling flu-like and stiff on waking,
    • broken or shallow sleep, altered sleep pattern or hypersomnia.
  • Cognitive difficulties (sometimes described as 'brain fog') , which may include:
    • problems finding words or numbers,
    • difficulty in speaking,
    • slowed responsiveness,
    • short-term memory problems, and difficulty concentrating or multitasking.

1.2.3 If ME/CFS is suspected, carry out:

  • medical assessment (including symptoms and history, comorbidities, overall physical and mental health)
  • a physical examination
  • an assessment of the impact of symptoms on psychological and social wellbeing
  • investigations to exclude other diagnoses, for example (but not limited to):
    • urinalysis for protein, blood and glucose
    • full blood count
    • urea and electrolytes
    • liver function
    • thyroid function
    • erythrocyte sedimentation rate or plasma viscosity
    • C-reactive protein
    • calcium and phosphate
    • HbA1c
    • serum ferritin
    • coeliac screening
    • creatine kinase.

      Use clinical judgement to decide on additional investigations to exclude other diagnoses (for example, vitamin D, vitamin B12 and folate levels; serological tests if there is a history of infection; and 9am cortisol for adrenal insufficiency).

1.2.4 Be aware that the following symptoms may also be associated with, but are not exclusive to, ME/CFS:

  • orthostatic intolerance and autonomic dysfunction, including dizziness, palpitations, fainting, nausea on standing or sitting upright from a reclining position.
  • temperature hypersensitivity resulting in profuse sweating, chills, hot flushes, or feeling very cold.
  • neuromuscular symptoms, including twitching and myoclonic jerks.
  • flu-like symptoms, including sore throat, tender glands, nausea, chills or muscle aches.
  • intolerance to alcohol, or to certain foods and chemicals.
  • heightened sensory sensitivities, including to light, sound, touch, taste and smell.
  • pain, including pain on touch, myalgia, headaches, eye pain, abdominal pain or joint pain without acute redness, swelling or effusion.

1.2.5 Primary healthcare professionals should consider seeking advice from an appropriate specialist if there is uncertainty about interpreting signs and symptoms and whether an early referral is needed. For children and young people, consider seeking advice from a paediatrician.

1.2.6 When ME/CFS is suspected:

  • continue with any assessments needed to exclude or identify other conditions
  • give the person advice on managing their symptoms in line with the section on advice for people with suspected ME/CFS.
Shopping Basket