How is Chronic Fatigue Syndrome / M.E. diagnosed?

How is Chronic Fatigue Syndrome / M.E. diagnosed?

Chronic Fatigue Syndrome (CFS), also known as Myalgic Encephalomyelitis (M.E.), is a complex and debilitating condition characterized by extreme fatigue that cannot be explained by any underlying medical condition. Diagnosing CFS/M.E. can be challenging as there are no specific tests or markers for the condition. Instead, healthcare professionals rely on a combination of medical history, physical examination, and exclusion of other possible causes to make a diagnosis.

Medical History

The first step in diagnosing CFS/M.E. involves a detailed medical history assessment. The healthcare provider will ask about the patient's symptoms, their duration, and any factors that may have triggered or worsened the fatigue. It is important for the patient to provide a comprehensive account of their symptoms, including the severity and impact on daily life activities.

Physical Examination

After reviewing the medical history, a physical examination is conducted to rule out other potential causes of fatigue. The healthcare provider will assess various body systems, including cardiovascular, respiratory, and neurological systems, to identify any abnormalities or signs of other illnesses. While physical examination findings may not directly confirm CFS/M.E., they help exclude other conditions that may present with similar symptoms.

Diagnostic Criteria

Diagnostic criteria are used to establish a diagnosis of CFS/M.E. The most widely accepted criteria are the Fukuda criteria and the Canadian Consensus Criteria (CCC). These criteria require the presence of severe fatigue lasting for at least six months, along with specific accompanying symptoms such as impaired memory or concentration, unrefreshing sleep, muscle pain, joint pain, headaches, and post-exertional malaise.

Fukuda criteria:

• Severe fatigue lasting at least six months


• Exclusion of other medical or psychiatric conditions that could explain the fatigue


• Presence of at least four accompanying symptoms, including impaired memory or concentration, unrefreshing sleep, muscle pain, joint pain, headaches, tender lymph nodes, and post-exertional malaise

Canadian Consensus Criteria (CCC):

• Severe fatigue lasting at least six months


• Exclusion of other medical or psychiatric conditions that could explain the fatigue


• Presence of at least eight accompanying symptoms, including impaired memory or concentration, unrefreshing sleep, muscle pain, joint pain, headaches, tender lymph nodes, post-exertional malaise, and others

Exclusion of Other Conditions

Since there are no specific tests for CFS/M.E., it is crucial to exclude other medical conditions that could explain the symptoms. The healthcare provider will order a series of tests to rule out alternative diagnoses. These may include blood tests, imaging studies, and other specialized investigations depending on the patient's specific symptoms and medical history. The purpose of these tests is to identify any underlying conditions that may mimic or contribute to the fatigue experienced by the patient.

Collaborative Approach

Diagnosing CFS/M.E. often requires a collaborative approach involving multiple healthcare professionals. Due to the complexity of the condition, patients may be referred to specialists such as rheumatologists, neurologists, or infectious disease specialists to ensure a comprehensive evaluation. This multidisciplinary approach helps to rule out other potential causes and increases the accuracy of the diagnosis.

Longitudinal Assessment

It is important to note that diagnosing CFS/M.E. is not a one-time event. The condition is often diagnosed based on a longitudinal assessment of symptoms and their impact on the patient's daily life. Healthcare providers may request follow-up visits to monitor the persistence and progression of symptoms over time, ensuring that the diagnosis remains appropriate.

In conclusion, diagnosing Chronic Fatigue Syndrome / M.E. relies on a thorough medical history assessment, physical examination, exclusion of other conditions, and adherence to specific diagnostic criteria. While there are no definitive tests for CFS/M.E., healthcare professionals use a combination of these approaches to make an accurate diagnosis and provide appropriate management strategies for patients.