Researchers believe they have developed the first dedicated blood test to diagnose chronic fatigue syndrome (CFS), also known as myalgic encephalomyelitis (ME), which has the potential to be a game-changer for millions around the globe who suffer from the debilitating condition.
Researchers from the University of East Anglia (UEA) and Oxford BioDynamics, in collaboration with The London School of Hygiene & Tropical Medicine and Royal Cornwall Hospitals NHS Trust, have announced they’ve successfully developed the first blood test for ME/CFS that delivers 92% accuracy in identifying the condition. This bypasses the current path of diagnosis, where symptoms are evaluated and a host of blood tests are performed to rule out other conditions such as thyroid problems or anemia.
It could also mean validation for people suffering from ME/CFS, a condition that’s often misdiagnosed and remains poorly understood, resulting in people living with it for a significant period of time before they get answers. Treatment is also challenging.
“This is a significant step forward,” said Dmitry Pshezhetskiy, a professor from UEA’s Norwich Medical School. “For the first time, we have a simple blood test that can reliably identify ME/CFS – potentially transforming how we diagnose and manage this complex disease.
“ME/CFS is a serious and often disabling illness characterized by extreme fatigue that is not relieved by rest,” he added. “We know that some patients report being ignored or even told that their illness is ‘all in their head.’ With no definitive tests, many patients have gone undiagnosed or misdiagnosed for years.”
The test was developed using Oxford BioDynamics’ EpiSwitch 3D Genomics technology, which analyzed DNA folding in blood samples taken from 47 patients with severe ME/CFS and 61 individuals without the condition. Each of our cells contains around two meters (6.6 feet) of folded DNA, which determine how genes are switched on and off. While the condition isn’t genetic – we’re not born with genetic mutations for it – in recent years scientists have gained greater knowledge of it having an epigenetic basis. Essentially, external influences change how genes are modulated, and the blood test can identify these markers of ME/CFS.
“Chronic fatigue syndrome is not a genetic disease you’re born with,” said Alexandre Akoulitchev, Chief Scientific Officer at Oxford BioDynamics (OBD). “That’s why using EpiSwitch ‘epigenetic’ markers – which can change during a person’s life, unlike a fixed genetic code – was key to reaching this high level of accuracy. The EpiSwitch platform behind this test, together with OBD’s vast 3D Genomic knowledge-base, has already been proven to deliver practical, rapid blood diagnostics accessible at scale.
“With this breakthrough, we are proud to enable a first-in-class test that can address an unmet need for a quick and reliable diagnostic for a complex, challenging-to-identify illness,” he added.
EpiSwitch technology has already been used in detecting markers in amyotrophic lateral sclerosis (ALS) and rheumatoid arthritis, and a blood test for prostate cancer – EpiSwitch PSE – is already in use, with 94% accuracy.
The researchers claim that the blood test identified 92% of the ME/CFS cases in the analysis cohort, however, some medical experts remain skeptical about whether this diagnostic tool is the breakthrough the team says it is.
“The authors are claiming a higher rate of sensitivity and specificity than in most other biomedical tests,” said Dr Alastair Miller, a retired physician in infectious disease and internal medicine. “My main concern with this study is the lack of appropriate controls. They are using healthy controls rather than those with other chronic conditions such as depression or fibromyalgia or even MS (multiple sclerosis). My worry is that it will prove to be yet another false dawn, launched with a huge amount of hype and will raise patients’ expectations unrealistically.”
Others have also questioned the method of testing for the condition, suggesting it’s too early to take the success at face value.
“Despite the test predicting 22 of 24 cases and 44 of 45 controls in independent samples, these claims are premature,” said Professor Chris Ponting, Chair of Medical Bioinformatics at the University of Edinburgh. “This is because results could be confounded in three ways: by (1) Sex and/or by age: sex- and age-matching was not done (beyond matching age criterion of 20-80 years old); (2) Batch: all cases were from the CureME Biobank, whereas most (41 of 61) controls came from the company’s own biobank; and, (3) Inactivity and severity: all cases had severe symptoms and were house-bound, whereas all controls were healthy and likely physically active.
“This test needs to be fully validated in better designed and independent studies before it is considered for clinical application,” he added. “Even if validated, the test will be expensive.”
Nonetheless, the research itself offers new clues as to the epigenetic triggers of ME/CFS and could also further our knowledge of identifying and treating long COVID.
“Understanding the biological pathways involved in ME/CFS opens the door to developing targeted treatments and identifying which patients might benefit most from specific therapies,” said Pshezhetskiy. “We hope that the Episwitch CFS test could become a vital tool in clinical settings, paving the way for more personalized and effective care.”
The researchers also added that wider database testing will be needed to confirm the findings that emerged from their testing population.
“Larger-scale, prospective validation in multi-centre cohorts will be essential to establish external validity,” they wrote. “The observed epigenetic changes may be downstream of chronic immune activation; longitudinal and interventional studies (e.g., before/after immunomodulatory therapy) are needed to test causality.”
In July, researchers at Jackson Laboratory announced their own diagnostic breakthrough for ME/CFS, with a test that identified the condition through specific immune cell and gut profiles.
The research was published in the Journal of Translational Medicine.
Source: University of East Anglia via MedicalXpress, Science Media Centre
