Researchers at Stanford University, California, have described a blood test for CFS/ME. Mononuclear cells respond differently to hyperosmotic stress in patients with the condition from how they do in normal controls. This, it is hoped, may provide a diagnostic test for the condition, which at present is diagnosed purely on symptoms.
This is encouraging, but Minerva in the BMJ thinks they used the wrong comparison group. “What’s important is not whether the test can tell healthy and ill people apart but if it can distinguish between chronic fatigue syndrome and other conditions in which symptoms of fatigue and tiredness are prominent.” This seems to be a valid comment.