Clinical Application of 2017 McDonald Diagnostic Criteria for Multiple Sclerosis

Abstract

Background and purpose: McDonald criteria for multiple sclerosis diagnosis have been revised over the years, diagnostic procedures have been simplified and earlier diagnosis facilitated. The new 2017 revision introduces other important changes, with a further simplification for the diagnosis. Oligoclonal bands reassume a more relevant role in the workup.

Methods: We describe 3 typical cases of patients admitted for clinically isolated syndrome and illustrate how the application of the new criteria can change the diagnostic approach with respect to the previous criteria.

Results: In two of the three cases a diagnosis of multiple sclerosis is now possible.

Conclusions: The new 2017 Multiple Sclerosis criteria may have an important impact in clinical practice with an earlier treatment to avoid the risk of disease dissemination. Their application requires a careful assessment to avoid misdiagnosis and mistreatments.

Keywords: McDonald criteria; clinically isolated syndrome; criteria; multiple sclerosis; oligoclonal bands.

Fig. 1. Brain coronal plane FLAIR-weighted and axial plane T2-weighted scan showing hyperintense lesions in the left frontal lobe (A and C) and in right centrum semiovale (B and D), spinal cord sagittal and axial plane T2-weighted showing hyperintense lesions at C2 (E and G), and D1–D2 level (E and H), with enhancement on T1 post-Gadolinium scan (F).

Fig. 2. Brain coronal plane FLAIR-weighted scan showing hyperintense juxtacortical (A), periventricular and infratentorial lesions (B and C) without enhancement on T1 post-Gadolinium scan (F and G), axial plane T2-weighted scan showing slight signal hyperintensity in left optic nerve (E), spinal cord sagittal plane T2-weighted showing hyperintense lesions at multiple levels (D) without enhancement on T1 post-Gadolinium scan (H).

Fig. 3. Brain axial plane FLAIR-weighted scan showing hyperintensity of the left peritrigonal white matter (A) and coronal and axial plane FLAIR-weighted scan showing slight hyperintensity in the right optic nerve (B and C) without clear enhancement on T1 post-Gadolinium axial and sagittal scan (D, E, and F).