Clinical Approach to ME/CFS
There is no "typical" case, but a patient history can be useful in educating physicians about ME/CFS (Box 1). This composite case history illustrates the key features of ME/CFS: significant reduction in ability to perform usual activities accompanied by profound fatigue; significant worsening of symptoms after minimal physical or mental exertion (termed postexertional malaise); unrefreshing sleep; cognitive difficulties; and orthostatic intolerance (such as dizziness and lightheadedness upon standing up). In addition, this patient experienced widespread muscle pain, joint pain, and unpredictable waxing and waning of symptoms. Persons with ME/CFS might be misunderstood because they appear healthy and often have no abnormalities on routine laboratory testing. Clinicians need to be alert to this difficulty and take the time to elicit a good history of the illness, which is critical in the differential diagnosis and can provide evidence of ME/CFS.
Clinical evaluation includes a thorough medical history, psychosocial history, complete physical examination, mental health assessment, and basic laboratory tests to screen for conditions that could cause symptoms similar to ME/CFS and that should be treated before attributing the illness to ME/CFS. The screening laboratory tests can include complete blood count with differential white blood cell count, sodium, potassium, glucose, blood urea nitrogen, creatinine, lactate dehydrogenase, aspartate transaminase, alanine transaminase, alkaline phosphatase, total protein, albumin, calcium, phosphorus, magnesium, thyroid stimulating hormone, free thyroxine, sedimentation rate, C-reactive protein, antinuclear antibodies, rheumatoid factor, and urinalysis. Patients might also have comorbid conditions such as fibromyalgia, irritable bowel and bladder, Sjögren's syndrome, chemical sensitivities, and allergies. Additional tests might be clinically indicated.
Morbidity and Mortality Weekly Report. 2016;65(5051):1434-1438. © 2016 Centers for Disease Control and Prevention (CDC)