Scientists have discovered a unique signature of chronic fatigue syndrome, also known as myalgic encephalomyelitis (CFS/ME), in the blood of patients with severe symptoms.
Using no fewer than 200 blood biomarkers, researchers at the University of East Anglia and the biotech company, Oxford Biodynamics, claim to have developed a test that can diagnose CFS/ME with 96 percent accuracy.
“This is a significant step forward,” says molecular biologist Dmitry Pshezhetskiy from UEA.
“We know that some patients report being ignored or even told that their illness is ‘all in their head’. 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.”
The findings raise hope for those seeking answers to their chronic pain, dizziness, and flu-like symptoms, but several independent experts and organizations remain wary of those numbers.
Alastair Miller, a retired physician not involved in the study, says that level of accuracy is “almost unheard of for this sort of test, so this is quite a remarkable claim.”
“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,” adds Miller.
Unlike prior investigations into blood tests for ME/CFS, this new study relies on numerous biomarkers, not just one or two. Still, the “strong systemic” signal found in severely affected patients was only ‘strong’ when compared against healthy controls.
The study did not analyze the blood of those with moderate or mild CFS/ME, or patients with other conditions that can cause similar symptoms.
Those are both necessary steps to a proper diagnostic test.
Applied statistician Kevin McConway, who was not involved in the study, explains that “there’s no guarantee” as to how the test would work for people with other chronic illnesses, like cancers or autoimmune conditions.
Earlier this year, scientists reviewed the current research on CFS/ME blood biomarkers, concluded that while no practical test yet exists, emerging results show promise for future clinical use.
When that day will come is unknown. For years now, scientists around the world have tested different approaches to diagnosing CFS/ME with varying levels of success.
The recent research from UEA and Oxford Biodynamics relies on epigenetic changes, which occur when our environment or behavior alters the way our genes are expressed.
Using an existing platform called Episwitch®, the team tested epigenetic regulators in 47 patients with severe CFS/ME and 61 healthy individuals of the same age.
Using 200 of these markers, tests could correctly pick the person with CFS/ME 96 percent of the time.
EpiSwitch® has already been used to create clinical tests for prostate cancer, using this same logic. But one of the reasons CFS/ME is so difficult to diagnose is that its symptoms are highly variable in just about every way.
Today, it’s unknown whether all patients are suffering from the same underlying cause or if a variety of causes are contributing to the same pathology.
There are also numerous crossovers with other conditions.
In a statement on the recent research, officials at the ME Association UK say that epigenetic profiling is “an important step forward in the search for a diagnostic blood test.”
However, an effective diagnostic test should be highly sensitive and specific to that condition.
“In 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,” they say.
“Consequently, 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.”
