McDonald Criteria Updates for MS Diagnosis Announced

Proposed revisions to the 2017 McDonald diagnostic criteria for multiple sclerosis (MS) were announced at the 40th Congress of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS). The updates, which will be published later this year, provide guidance on the use of imaging, biomarkers, and disease dissemination in time (DIT) in MS diagnosis. The proposed revisions also include specific guidance for the diagnosis of radiologically isolated syndrome (RIS). The updates were developed and presented by the Advisory Committee on Clinical Trials in Multiple Sclerosis, an international panel of experts supported by ECTRIMS and the US National Multiple Sclerosis Society.

The McDonald criteria, which were originally introduced in 2001, have been revised multiple times, most recently in a set of updates published in 2017 in The Lancet Neurology. The proposed revisions announced at ECTRIMS 2024 are expected to enable earlier diagnosis of MS, potentially facilitating timely treatment and fewer instances of misdiagnosis.

• Imaging: The proposed updates provide guidance on implementing new imaging technology into MS diagnosis, including optical coherence tomography (OCT), MRI T2-weighted hyperintense foci imaging, and MRI imaging of the brain and spinal cord, as well as central vein sign (CVS) and optic nerve imaging.
• Biomarkers: In addition to imaging biomarkers, the updates detail the use of kappa free light chain (kFLC) and serum neurofilament light chain (NfL) biomarker measurement as well as cerebral spinal fluid (CSF) biomarkers.
• RIS: The proposed revisions will recommend the diagnosis of RIS as MS in particular cases based on the measurement of CVS lesions given that RIS develops into MS in <10 years in the majority of individuals.
• DIT: The panel of experts that proposed the new updates suggest substituting the use of DIT in MS diagnosis with dissemination in space (DIS) alone.
• Older People with MS: The revised guidelines suggest implementing stricter criteria when diagnosing people with MS aged >50 years who also have headache or vascular disorders.

Further details about the criteria are forthcoming. An announcement was made at the conference about an upcoming course that will present the new criteria to clinicians: https://ectrims.eu/app/uploads/2024/08/ECTRIMS_Winter-School-2025_scientific_programme_Homepage.pdf