Misdiagnosis of myalgic encephalomyelitis and chronic fatigue syndrome

The misdiagnosis of myalgic encephalomyelitis and chronic fatigue syndrome is very common, this takes the form of misdiagnosis, underdiagnosis or overdiagnosis.

Misdiagnosis
Misdiagnosing of ME or CFS involves diagnosing another illness or medical condition instead of diagnosing ME or CFS, for example erroneously diagnosing depression, medically unexplained physical symptoms, the symptom chronic fatigue or even a different fatiguing illness, or diagnosing ME or CFS when another illness or symptom is the cause of the symptoms, and diagnostic criteria for ME/CFS are not met.

Underdiagnosis
Underdiagnosis means failing to diagnose ME or CFS in patients meeting diagnostic criteria, e.g. blaming lifestyle factors for symptoms, or referring to patients as tired all the time. Patients may even be told they are in "good health" resulting in no medical care, or be diagnosed as having another illness or "medically unexplained symptoms".

Overdiagnosis
Overdiagnosis involves diagnosing ME or CFS when it is not present, meaning when the patient does not meet the diagnostic criteria for ME or CFS, especially diagnosing CFS instead of chronic fatigue or idiopathic chronic fatigue is the cause of the symptoms.

While there is no diagnostic medical test for ME or CFS, medical tests must be run to identify illness that have similar symptoms but can be identified by particular tests.

Overdiagnosis of chronic fatigue syndrome can also result when CFS is diagnosed or referred interchangably with either chronic fatigue (CF), or another illness, e.g., regarding all fibromyalgia patients as having CFS or using myalgic encephalomyelitis (ME) to refer to patients meeting CFS diagnostic criteria but not ME diagnostic criteria. Sometimes an CFS diagnosis is when chronic fatigue or chronic pain (or both) are present and fully explained by another fatiguing illness.