Researchers have developed the first-ever blood test that can diagnose myalgic encephalomyelitis, also known as chronic fatigue syndrome (ME/CFS).
There is no current test for the condition and medics usually diagnose patients based on their symptoms, but as a result, many patients can go undiagnosed for years.
Now, academics have made a âbreakthroughâ in the diagnosis of ME/CFS by developing the first-ever blood test for the condition.
But other experts and academics have called for more studies to confirm the findings.
âME/CFS is a serious and often disabling illness characterised by extreme fatigue that is not relieved by rest,â said lead researcher Professor Dmitry Pshezhetskiy, from the University of East Angliaâs (UEA) Norwich Medical School.
âWe know that some patients report being ignored or even told that their illness is âall in their headâ, with no definitive tests, many patients have gone undiagnosed or misdiagnosed for years.
âWe wanted to see if we could develop a blood test to diagnose the condition â and we did.
âOur discovery offers the potential for a simple, accurate blood test to help confirm a diagnosis, which could lead to earlier support and more effective management.â
Scientists led by experts from UEA and Oxford Biodynamics (OBD) set out to examine how DNA is folded in patients diagnosed with the condition, which might provide tell-tale signs of ME/CFS.
Using OBDâs EpiSwitch 3D Genomics technology, they looked at blood samples from 47 patients with severe ME/CFS and 61 healthy adults.
The team discovered a unique pattern that appears consistently in people with ME/CFS that is not seen in healthy people, enabling them to develop the test.
Writing in the Journal of Translational Medicine, experts said the test has a sensitivity â or the likelihood of a test being positive if that patient has the condition â of 92%.
And it has a specificity â the probability the test will rule out negative cases â of 98%, they added.
Prof Pshezhetskiy added: âThis is a significant step forward, for the first time, we have a simple blood test that can reliably identify ME/CFS â potentially transforming how we diagnose and manage this complex disease.â
âAdditionally, 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.
âWe hope that the Episwitch CFS test could become a vital tool in clinical settings, paving the way for more personalised and effective care.â
OBD chief scientific officer, Alexandre Akoulitchev, added: âChronic Fatigue Syndrome is not a genetic disease youâre born with, thatâs why using EpiSwitch âepigeneticâ markers â which can change during a personâs life, unlike fixed genetic code â was key to reaching this high level of accuracy.
âThe EpiSwitch platform behind this test has already been proven to deliver practical, rapid blood diagnostics accessible at scale.
âWith 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.â
But other experts called for more studies to confirm the finding, and for the test to be assessed among a wider population of patients.
Commenting on the finding, Dr Charles Shepherd, medical adviser for The ME Association, said: âThese results, using epigenetic profiling, appear to be an important step forward in the search for a diagnostic blood test.
âHowever, as the researchers point out, a diagnostic blood test has to be both highly sensitive and specific to that condition.
âIn this case, we therefore need to know whether the abnormality is consistently present in the very early stages of ME/CFS as well as in people with longstanding disease who have mild or moderate ME/CFS.
âWe also need to know that, in addition to the abnormality not being present in healthy controls, it is also not present in a range of other chronic inflammatory and autoimmune diseases that cause ME/CFS-like symptoms and form part of the differential diagnosis of ME/CFS.
âConsequently, further research needs to be carried out to properly validate and repeat these findings before concluding that we do now have a highly sensitive and specific diagnostic blood test for ME/CFS.â
Professor Chris Ponting, chairman of medical bioinformatics at the University of Edinburgh, added: âThis test needs to be fully validated in better-designed and independent studies before it is considered for clinical application.
âEven if validated, the test will be expensive, likely (about) ÂŁ1,000.â
CFS/ME is a long-term condition that can affect different parts of the body, the most common symptom is extreme tiredness.
Estimates suggest that more than 400,000 people in the UK are impacted by the condition.
Researchers said they hope the development will also pave the way for a test to diagnose long Covid.
