Could Chronic Fatigue Syndrome be Caused by a Virus?
A report was recently published in one of the most prestigious scientific journals that a virus called “xenotropic murine leukemia virus related virus” was recently found to infect 67% of white blood cells of chronic fatigue syndrome patients, but only ~4% of normal individuals (Lombardi et al., Science, Oct. 2009). This finding was covered in the New York Times, Wall Street Journal, and several other major publications, as it seemed to provide an answer to the conundrum of chronic fatigue syndrome, which did not have a known cause. If a virus caused chronic fatigue syndrome, it could potentially be treated with anti-viral medications, much like is done with HIV.
But how well was the study done? A close review of the figures showed several inconsistencies. It appeared that there was actually evidence of a viral protein DNA in several of the “normal” controls, that was not counted in the final results. One of the experiments in which they tried to show that the virus produced an infection in a new cell did not seem to show the positive conclusions they derived. Additionally, there were typos and unclear descriptions of methodology, raising questions about how well the work was done. There were other worrying signs. After the paper was published, the senior author said that there was evidence of viral infection in 95% of patients, a much larger percentage than reported in the actual paper. Given the seemingly arbitrary way in which some of the experiments were called “positive” and others “negative”, this claim is hard to believe, and it is possible that the increased numbers reflect poor methodology that yields false positive results.
Despite all of these uncertainties, the question for a chronic fatigue syndrome patient, many of whom have suffered for years, is, “Could this possibly be helpful for me?” If, for example, XMRV were actually a causative agent in chronic fatigue syndrome, and a patient tested positive for the virus, an anti-viral medication might theoretically be able to decrease viral replication and thus improve symptoms. However, there are serious side-effects to anti-viral medications that make their utilization potentially dangerous, and any such usage would be “off-label”, opening up physicians who prescribed them for chronic fatigue syndrome to a wide range of lawsuits. As the benefit is unclear, there is cause for caution, for both patients and physicians. Additionally, as the detection method for the virus is not yet standardized, it is possible that the laboratory doing the testing might do so sloppily, and provide a positive result when the patient is actually negative, or vice versa.
At this stage, there is both promise and peril in the testing of XMRV. The true impact of the discovery of XMRV in chronic fatigue syndrome will not be known until many more studies – of independent authorship from the original group — are completed.
” However, there are serious side-effects to anti-viral medications that make their utilization potentially dangerous”
what now , should the ppl with cfs wait until side effectless antivirals ? ..
how can someone with such a reasoning logic whatever graduate a medical school ?
I think its pretty clear if you read the article that the author says there is “cause for caution”, not “don’t use these at all.” For any patient and doctor, the use of medications should be a decision made between the two of them, and some patients may decide that the potential downside outweighs the benefits, whereas other may be willing to risk adverse effects to potentially alleviate many of their symptoms.