Doubts over US scientists’ test for chronic fatigue syndrome
A ROW has developed over chronic fatigue syndrome (CFS) after scientists at Stanford University said they had developed a test that proved the condition existed, while British experts disputed their findings.
CFS, which is sometimes known as myalgic encephalomyelitis (ME) affects around 250,000 people in Britain and is characterised by extreme tiredness, muscle pain, sleep disorders, headaches and flu-like symptoms.
Many scientists believe the condition is caused by the immune system failing to shut down properly after an illness, infection or traumatic event. It is difficult to diagnose, with doctors relying on self-reported symptoms.
Scientists at Stanford School of Medicine in the US say they have developed a blood test that picks up CFS 100 per cent of the time. The test monitors electrical activity in immune cells under stress. Too much activity suggests the cell – and consequently the immune system – has gone into overdrive.
Dr Ron Davis, a professor of biochemistry and genetics, said: “We don’t know exactly why the cells and plasma are acting this way. But there is scientific evidence that this disease is not a fabrication of a patient’s mind. We see a
‘The issue is, can any biomarker distinguish CFS patients from those with other fatiguing illnesses?’
difference in the way healthy and chronic fatigue syndrome immune cells process stress.”
A trial was carried out on 20 people with CFS and 20 people without and accurately flagged all CFS patients and none of the healthy individuals.
However, experts in Britain said the test might be picking up symptoms of fatigue or anxiety rather than the disease itself, and could not be used as proof the condition is real.
Prof John Martin, of University College London, said: “If a test is to have meaning it has to be able to be applied to a population of patients who can be defined clinically. The patients had a variety of symptoms that could have arisen from a variety of causes.
“Furthermore, the authors do not relate the cellular finding in the test to a possible cause of the disease... The authors should consider whether their test is related to an effect of symptoms and not related to the cause.”
Prof Sir Simon Wessely, president of the Royal Society of Medicine, added: “The problem is not differentiating patients with CFS from healthy controls. The issue is, can any biomarker distinguish CFS patients from those with other fatiguing illnesses? And second, is it measuring the cause, and not the consequence, of illness? This study does not provide evidence that either has been achieved.”