Table 4 Comparison of findings in vasculitis and demyelinating diseases

CSF cell count

Normal-mild pleocytosis < 50cells/uL

Pleocytosis: 31- > 100cells/uL [13]

Pleocytosis: mild to > 50cells/uL range (6–380) [14]

Pleocytosis to variable degree

CSF cell differential

Lymphocytes predominance

Mostly lymphocytes and monocytes

Can include neutrophils, lymphocytes [14]

Usually lymphomonocytic dominance [15]

CSF protein

Normal to slightly elevated

Normal to mildly elevated

Normal to mildly elevated

Mild to moderate elevation

Oligoclonal band

 > 90%

Rare (< 10%) [13]

rare

rare

IgG index

Usually elevated

Usually elevated

Usually elevated

rare

Brain MRI characteristic findings

Characteristic round, ovoid lesions > 5 mm in periventicular, juxtacortical, brainstem and cerebellar involvement (peduncles)

Variable- no specific characteristics: usually multifocal subcortical WM, deep grey matter, brainstem involvement; compared to NMO-AQP4 + presence of cortical/subcortical WM distinguish; area postrema involvement is rare [16]; FLARE/FUEL (focal FLAIR-abnormality on brain MRI accompanied by leptomeningeal enhancement)

Typically follows AQP4 distribution: hypothalamic, brainstem periependymal, lesion of area postrema and splenium lesion [17] 

Variable: multifocal parenchymal ischemic change, can have small area of hemorrhage, can have meningeal enhancement

Histologic findings

Perivenular lymphocytic cuffing and white matter degeneration

Perivenular lymphocytic cuffing and confluent white matter degeneration

Astrocyte lysis followed by infiltration of neutrophils in brain parenchyma and reactive gliosis

Transmural lymphocytic infiltrate with damage to the vascular wall (with or without fibrinoid necrosis) including arterioles, capillaries, and to a lesser extent, venules