Diagnosis of multiple sclerosis: A review of the 2017 revisions of the McDonald criteria

Abstract

The revolutionary progress of research in neuroimmu-nology has led to the introduction of disease modifying therapies in multiple sclerosis at the end of the last century. The International Panel on Diagnosis of Multiple Sclerosis originally proposed the 2001 McDonald criteria to facilitate the diagnosis of MS in patients with the first objective neurological symptom(s) suggesting demyelinating event, when magnetic resonance imaging is integrated with clinical and other paraclinical diagnostic methods. New terms have been introduced to substitute clinical information by MRI: dissemination in space - indicating a multifocal central demyelinating process and dissemination in time - indicating the development of new CNS lesions over time. The criteria for diagnosis of Multiple Sclerosis have continuously evolved, they were modified in 2005 and 2010 allowing for an earlier and more accurate diagnosis of MS over time, and they provided the most up-to-date guidance for clinicians and researchers. The last recommended revisions relied entirely on available evidence, and not on expert opinion thereby reducing the risk of the misdiagnosis. The 2017 McDonald criteria continue to apply primarily to patients experiencing a typical, clinically isolated syndrome. In this review, we provide an overview of the recent 2017 revisions to the criteria of dissemination in space and time with the importance of the presence of CSF-specific oligoclonal bands; keeping fully in mind that there is no better explanation for symptoms than diagnosis of MS. In the future, validation of the 2017 McDonald criteria will be needed in diverse populations. Further investigations are required on the value of new MRI approaches, on optic nerve involvement, on evoked potential and optical coherence tomography, in order to assess their possible contribution to diagnostic criteria.