Heterogeneity in Multiple Sclerosis: Scratching the Surface of a Complex Disease

Table 1

Classic MS and its variants.

Classic MS	MS variants
(i) Relapsing-remitting (RRMS): 85% of all MS cases at onset	(i) Neuromyelitis Optica (NMO)
(ii) Second ary progressive (SPMS): 70%–80% of RRMS cases after 10 years from disease onset	(ii) Balo’s concentric sclerosis
(iii) Primary progressive (PPMS): 15% of all MS cases at onset	(iii) Margburg’s MS variant
(iv) Progressive-relapsing (PRMS): very small percentage	(iv) Schilder’s MS variant