NEW findings presented at the ACTRIMS Forum 2025 highlight how the latest revisions to the McDonald Criteria could reshape the diagnosis of multiple sclerosis (MS), allowing for earlier identification in patients with radiologically isolated syndrome (RIS) and atypical clinical presentations.
Traditionally, MS diagnosis required evidence of clinical attacks or progressive neurological disability. However, the 2024 McDonald Criteria now permit diagnosis based solely on MRI evidence, provided specific markers such as dissemination in time (DIT) and space (DIS) are met. Additionally, the presence of six or more central vein sign (CVS)-positive lesions or cerebrospinal fluid (CSF)-specific immunoglobulin synthesis can further support an MS diagnosis.
Researchers applied these criteria to 420 participants in the CAVS-MS study, which evaluates diagnostic biomarkers for MS. Of these, 166 had atypical symptom onset, and 25 had a purely radiological presentation. Applying the revised criteria, 36 out of 191 participants (19%) with atypical or radiological-only presentations met the threshold for an MS diagnosis. Notably, among those meeting DIS criteria alone, 37% were CVS-positive, 29% had oligoclonal bands (OCB) in their CSF, and 10% met both criteria.
These findings suggest that the revised McDonald Criteria significantly broaden the pool of individuals eligible for an MS diagnosis. This has critical implications for early intervention, as initiating disease-modifying therapies sooner is associated with improved long-term outcomes.
The study also underscores the utility of the central vein sign as a key diagnostic tool, reinforcing its value in confirming MS in patients without typical clinical symptoms. With mounting evidence supporting the importance of MRI-based markers, neurologists may need to reconsider how they evaluate patients with suspected MS in the absence of overt symptoms.
As the field continues to evolve, these updates could lead to earlier and more accurate diagnoses, potentially altering treatment paradigms and improving patient outcomes.
Reference: Scharf A et al. Application of 2024 McDonald Criteria to individuals with atypical and radiological only presentations in a multicenter diagnostic biomarker study. Presented at ACTRIMS Forum 2025, West Palm Beach, Florida, USA, February 27 – March 1.
Anaya Malik | AMJ
