Chronic fatigue syndrome can now be identified through bio-markers in the blood, revealed scientists at Columbia University's Mailman School of Public Health. The study offers hope that earlier diagnosis may improve treatment. This is the first robust physical evidence that the syndrome is a biological illness as opposed to a psychological disorder, and also the first evidence that the disease has distinct stages.
With no known cause or cure, chronic fatigue syndrome, known formally as encephalomyelitis (ME/CFS), can cause extreme tiredness, headaches, difficulty concentrating and muscle pain.
Lead author Mady Hornig said, "We now have evidence confirming what millions of people with this disease already know, that ME/CFS isn't psychological. Our results should accelerate the process of establishing the diagnosis after individuals first fall ill as well as discovery of new treatment strategies focusing on these early blood markers."
Researchers tested levels of 51 immune bio-markers in blood plasma samples from 298 patients and 348 healthy controls. They found higher levels of immune molecules called cytokines in patients who had the disease three years or less. These patterns were not visible in healthy controls or patients who had the syndrome for more than three years.
Hornig said, "The association was unusually strong with a cytokine called interferon gamma that has been linked to the fatigue that follows many viral infections, including Epstein-Barr virus. However, cytokine levels did not explain symptom severity, which often fluctuates. Patients may have good days and bad days. It appears that ME/CFS patients are flush with cytokines until around the three-year mark, at which point the immune system shows evidence of exhaustion and cytokine levels drop."
Senior author W. Ian Lipkin said, "This study delivers what has eluded us for so long: unequivocal evidence of immunological dysfunction in ME/CFS and diagnostic bio-markers for disease. The question we are trying to address in a parallel microbiome project is what triggers this dysfunction."
The report appears in the journal Science Advances.