Dr. Amit Bar-Or, an assistant professor in neurology and neurosurgery at the Montreal Neurological Institute and an associate in microbiology and immunology at McGill University in Montreal, Canada, contributed to an editorial that accompanied the NEJM article. Below, Bar-Or discusses the need for a reliable MS blood test and how it might affect treatment decisions.
How is MS traditionally diagnosed?
Most patients will come to the doctors when they have their first neurological episode, which may involve a range of different symptoms or signs. This first episode is called a clinically isolated syndrome.
The part of the nervous system that is involved in an attack will determine what kind of symptoms or signs a patient has. These may include loss of vision, problems with weakness, lack coordination of the limbs, unsteadiness while walking or a loss of sensation or a tingling sensation in the limbs, trunk or face.
A segment of patients will end up having just that isolated event .However, another portion will go on to have a second episode and eventually end up with a diagnosis of multiple sclerosis. Patients are only diagnosed with MS if they had two or more neurological episodes.
What diagnostic tests are available for MS?
What has been most helpful in identifying people who will transition to an MS diagnosis is a type of brain imaging called magnetic resonance imaging (MRI). Research shows that if you look at an MRI of the brain at the time of the first episode, the presence or absence of lesions associated with demyelination, or a loss of myelin, can be helpful in predicting the likelihood of eventually having a second attack, and consequently a multiple sclerosis diagnosis.
