Evolving MS Diagnostic Criteria: 2024 McDonald Criteria and What's New

Welcome back to another Neurology Live Peer Exchange series. In this episode titled "Evolving MS Diagnostic Criteria: 2024 McDonald Criteria and What's New," moderator Dr. Mitzi Joi Williams discusses multiple sclerosis with Dr. Stephen Krieger.

The program opens with Dr. Williams introducing the peer exchange, titled "Evaluating Anti-CD20 Therapies in Multiple Sclerosis: From Early Treatment Strategy to Long-Term Clinical Management." The faculty introduce themselves: Dr. Krieger is an MS specialist at Mount Sinai in New York; Dr. Greenberg is a professor of neurology at UT Southwestern in Dallas; and Dr. Bove is an MS specialist at UCSF.

Dr. Williams turns to the 2024 McDonald criteria — published in 2025 and now being adopted— and asks Dr. Krieger for a high-level overview. Dr. Krieger notes several changes: the addition of the optic nerve as a fifth disease topography; new MRI sequences such as the central vein sign and paramagnetic rim lesions; and criteria that allow a formal MS diagnosis in patients with radiologically isolated syndrome (RIS) who have never had a clinical symptom.

While applauding the intent to move toward a biological disease definition, Dr. Krieger expresses concern that the new criteria are more complex and difficult to apply in non-academic or under-resourced settings, where advanced MRI sequences and specialist radiologists may not be available. Dr. Greenberg adds that broadening the diagnostic pool carries unintended consequences: therapies currently used may not have been tested in the newly included patient populations.

In the next episode, "MS Treatment Strategy: High-Efficacy Therapy vs. Escalation Approach," the panel debates the shift from traditional "start low, go slow" escalation therapy to leading with high-efficacy treatments for relapsing MS.