Implementing the 2024 revision of the McDonald diagnostic criteria for multiple sclerosis in Germany: Practical...

Early and reliable diagnosis of multiple sclerosis (MS) is critical for initiating an appropriate disease-modifying therapy (DMT). The 2024 revisions of the McDonald diagnostic criteria incorporate novel fluid and imaging biomarkers aiming to facilitate an accurate and timely diagnosis. The aim of this point-of-view paper is to discuss the implementation of the 2024 McDonald criteria in the clinical routine setting in context of the German Health care system and provide consensus recommendations by an interdisciplinary expert panel. A multidisciplinary panel of nine experts in the field of diagnosis and treatment of MS convened to discuss the potential advances and challenges of the clinical implementation of the 2024 McDonald criteria and develop consensus recommendations. The panel identified implementation challenges regarding limited specialized resources for the suggested additional imaging markers such as the detection of optic nerve (ON) lesions, paramagnetic rim lesions (PRLs) and the demonstration of lesions with a central vein sign (CVS) as well as the implementation of kappa free light chains (kFLC) in Germany. We advocate a stratified diagnostic approach: cerebrospinal fluid (CSF) analysis remains essential. The consideration of ON lesions, PRLs and lesions with a CVS should be reserved for diagnostic situations in which the diagnosis cannot be established with conventional MRI protocols or other methods for examination of the optic nerve. To minimize misdiagnosis and to address the complexity of treating radiologically isolated syndrome, there is a necessity of continuous professional training and nuanced, patient-centered therapeutic strategies, especially for individuals with radiologically isolated syndrome but also for atypical presentations. In conclusion, the 2024 revisions of the McDonald criteria aim to facilitate an accurate and early diagnosis of MS potentially enabling earlier MS therapy initiation. However, the routine implementation, particularly regarding the new imaging markers, requires an expansion of resources and expertise limiting the general applicability in the German healthcare system.