By Miriam Tucker
An investigational blood test appears to reliably distinguish individuals with myalgic encephalomyelitis/chronic fatigue syndrome (ME / CFS) from healthy persons and may serve as a low-cost diagnostic for the illness, new data suggest.
Rahim Esfandyarpour, PhD, from the University of California, Irvine (who was formerly at Stanford University) and colleagues reported their findings on the nanoelectronics blood-based test today in the Proceedings of the National Academy of Sciences.
There is currently no well-established biological diagnostic test for ME / CFS, an often-debilitating disease that affects about 2 million people in the United States. The diagnosis is currently based on symptoms, and a majority of individuals with the condition are believed to be undiagnosed.
The new assay detects differences in impedance patterns in response to hyperosmotic stress between blood samples from ME / CFS patients and those from healthy persons. It “can potentially establish a diagnostic biomarker and a drug-screening platform for ME / CFS in conjunction with preexisting evaluation measures. This is a low-cost, rapid, miniaturized, minimally invasive, and highly sensitive assay,” the authors write.
They say that, given the assay’s significance and reliability, “we envision it has the potential to be widely employed in other research laboratories and clinics in the near future as an aid to physicians as well as to our colleagues in the ME / CFS research community.”
Assay Definitively Shows ME / CFS Has Biological Roots
Ronald W. Davis, PhD, professor of biochemistry and genetics at Stanford University and director of the Stanford Genome Technology Center, California, is the senior author of the study. Davis was a coinvestigator of the landmark 2001 human genome sequencing project. He shifted the focus of his research to ME / CFS because his adult son has been bedridden and completely disabled with the illness for the past several years, according to the Washington Post.
In the new study, the assay differentiated blood samples from 20 patients with moderate to severe ME / CFS (diagnosed using the 2003 Canadian Consensus Criteria) and 20 healthy control persons with 100% accuracy.
The authors note that they haven’t yet tested the assay in people with other medical conditions to determine whether it is uniquely identifying individuals with ME / CFS or those with a more general state of illness.
However, for now, that’s not as important as demonstrating a clear abnormality, given the skepticism among some in the medical community about the biological basis for the condition, Davis told Medscape Medical News in an interview during a recent 2-day National Institutes of Health (NIH) meeting where he had presented a preview of the data.
“It’s a potential diagnostic test…. Most of the time, patients hear, ‘There’s nothing wrong with you.’ Our major focus is to say that these patients have something wrong with them,” Davis continued. “At this point, whether this tests positive in other illnesses is irrelevant. The point is, they’re not healthy. Let’s figure out what’s wrong with them…. That’s number one. The second thing would be to look at lots of other patients and see what they show.”