MULTIPLE SCLEROSIS-DIAGNOSIS
SUMMARY
1. The traditional (Posner) criteria incorporated signs and symptoms indicating 2 CNS lesions separated in time and space and not caused by other CNS disease.
2. The current McDonald criteria relies more on MRI findings & less on CSF findings than the Posner criteria.
3. T1 gadolinium MRI shows the characteristic enhancement or "plaques" of patchy myelin loss (white matter disease) with 90% sensitivity.
4. T2 weighted MRI shows MS lesions as hyperintense areas: "Dawson's fingers" refers to MS lesions around the vessels that radiate out from the ventricles.
5. 90% of MS patients have increased lgG index and oligoclonal IgG bands in the CSF.
6. CSF protein and cell count is generally normal, a mild CSF lymphocytosis may be present, but no more than 50 cells/mm3.
7. Evoked action potentials (visual, brainstem auditory, and somatosensory evoked potentials) can help to establish the diagnosis of MS by identifying a clinically silent 2nd lesion.
Reference(s)
Wilkinson, I., Furmedge, D. and Sinharay, R. (2017). Oxford handbook of clinical medicine. Oxford: Oxford University Press. Get it on Amazon.
Feather, A., Randall, D. and Waterhouse, M. (2020). Kumar And Clark’s Clinical Medicine. 10th ed. S.L.: Elsevier Health Sciences. Get it on Amazon.
Hannaman, R. A., Bullock, L., Hatchell, C. A., & Yoffe, M. (2016). Internal medicine review core curriculum, 2017-2018. CO Springs, CO: MedStudy.
Therapeutic Guidelines. Melbourne: Therapeutic Guidelines Limited. https://www.tg.org.au [Accessed 2021].