New MS Diagnosis Rules May Help Spot Early Disease Signs
By MS Buddy ·
Summarized from EBioMedicine, Oct 2026 · PubMed. AI-generated summary. Not medical advice.
Research by Serena Borrelli, Pietro Maggi and 12 colleagues at Université catholique de Louvain, Université Libre de Brussels and 2 other institutions in Belgium.
Key Takeaway
The 2024 MS diagnosis rules identified some people who did not meet the older rules but already had blood and brain scan signs of MS-like damage.
What They Found
Researchers studied 141 people, including 95 who did not meet the 2017 MS diagnosis rules. Under the 2024 rules, 46 of those 95 people met the requirements for an MS diagnosis. Compared with those who still did not meet the rules, this group had higher levels of a blood marker that can rise when nerve fibers are damaged. Their brain scans also showed more MS-like spots and a smaller thalamus, a part of the brain that helps pass messages between areas. Their test results looked similar to those of people diagnosed under the older rules, and the blood marker was one of the strongest clues to later disease activity in a smaller follow-up analysis.
Who Should Care and Why
This study may matter most to people whose brain scan shows possible MS changes but who have few or no symptoms. It may also help people with symptoms whose test results did not meet the older diagnosis rules. For these people, the newer rules could help their care team recognize MS-like changes sooner. If you are in this situation, ask your MS specialist what the newer rules mean for your diagnosis and whether any further tests or follow-up scans would help. Caregivers can help by keeping a record of new symptoms and questions to bring to appointments.
Important Considerations
This study looked back at existing information, so it cannot prove that using the newer rules improves long-term health. Only 52 people were included in the analysis of later disease activity, so its predictions need more testing. A blood marker or brain scan finding is one piece of the puzzle, not a diagnosis or treatment decision on its own.
AI-generated summary — for informational purposes only, not medical advice
Read the original abstract
Published in EBioMedicine by et al.. Reproduced from the PubMed record.
The 2024 McDonald criteria broaden the definition of multiple sclerosis (MS), enabling diagnosis in individuals with asymptomatic MRI findings or clinical presentations not meeting the 2017 criteria. We assessed whether these criteria identify such cases using independent laboratory/imaging biomarkers and whether these biomarkers predict subsequent disease activity. Participants with asymptomatic MRI findings or clinical presentations not meeting the 2017 criteria were included and stratified according to the 2024 criteria. Serum neurofilament light chain (sNfL) and 3T brain MRI measures-including normalised brain volumes, T2 lesion load (T2LL), cortical lesion (CL) and paramagnetic rim lesion (PRL)-were compared between McDonald2024-positive and McDonald2024-negative groups, and with age/sex matched McDonald2017-positive cases according to the 2017 criteria; predictors of disease activity were assessed using penalised-Cox regression. A total of 141 participants were included: 95 not meeting the 2017 criteria (n = 64 asymptomatic MRI findings; n = 31 clinical presentations), stratified as McDonald2024-positive (n = 46) or McDonald2024-negative (n = 49), and 46 McDonald2017-positive cases. McDonald2024-positive vs. McDonald2024-negative cases showed higher age-corrected sNfL Z-scores (median 0.28[IQR 0.76] vs. -0.12[0.82], p = 0.003/pFDR = 0.006), reduced normalised thalamic volume (mean 0.009±[SD]0.0007 vs. 0.010 ± 0.0007, p = 0.003/pFDR = 0.006), and higher CL (1[4] vs. 0[0], p < 0.001/pFDR < 0.001) and PRL (1[1] vs. 0[0], p < 0.001/pFDR = 0.003) counts (differences remaining significant after age/sex, disease duration and T2LL adjustments). Biomarker profiles were comparable between McDonald2024-positive and McDonald2017-positive cases. Penalised-Cox regression (n = 52) identified sNfL Z-score and PRL presence as the most consistently selected predictors of disease activity, with higher bootstrap stability for sNfL (0.84) than PRL (0.76), and good model discrimination (C-index = 0.71). The 2024 McDonald criteria identify individuals not meeting the 2017 criteria who already exhibit MS-like neuroinflammatory/neurodegenerative pathological changes. These are reflected by laboratory and imaging biomarkers, including sNfL, which may predict subsequent disease activity and complement current diagnostic frameworks to support early clinical decision-making. King Baudouin Foundation; Cliniques Universitaires Saint-Luc; Fondation Charcot Stichting; Fund for Scientific Research (FNRS); ECTRIMS; Biogen; Sanofi.
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