With more and more people having brain MRIs for various reasons, doctors are finding people whose scans show signs of multiple sclerosis (MS) even though they have no symptoms of the disease. A new study published in the December 10, 2008, online issue of Neurology, the medical journal of the American Academy of Neurology, found that a third of these people developed MS within an average of about five years.
The study involved 44 people who had brain scans for various reasons, such as migraine headaches or head trauma, that showed abnormalities similar to those that occur in MS. The researchers confirmed that the abnormalities were the same as in MS and ruled out other possible causes. Then the researchers monitored the participants to determine whether they developed the disease.
Within an average of 5.4 years, 30 percent of the participants had developed MS symptoms. The brain scans of an additional 29 percent of the people showed further abnormalities, but they continued to have no symptoms of the disease.
"More research is needed to fully understand the risk of developing MS for people with these brain abnormalities, but it appears that this condition may be a precursor to MS," said study author Darin T. Okuda, MD, of the University of California, San Francisco, the UCSF Multiple Sclerosis Center and a member of the American Academy of Neurology.
Okuda and his colleagues are calling the condition the radiologically isolated syndrome (RIS).
Okuda said further research is also needed before any recommendations can be made regarding treatment. Editorial author Dennis Bourdette, MD, of Oregon Health & Science University in Portland and a Fellow of the American Academy of Neurology, took a stronger stand, noting that seven of the study participants had received MS treatment before they were referred to the UCSF MS center.
"Diagnosing a patient with MS has serious psychosocial and treatment implications, and physicians have an obligation to follow appropriate criteria in making the diagnosis," Bourdette said. "Patients must have symptoms to receive a diagnosis. This study sets the stage for establishing a process for evaluating these patients and following them to help determine the risk of developing MS. Until then, we should not tell them that they have MS or treat them with disease-modifying therapies. For now, it's best to remember the wise advice that we 'treat the patient, not the MRI scan.'"
Source: American Academy of Neurology
Explore further: Salmonella and Campylobacter show significant levels of resistance to common antimicrobials in humans and animals