The importance of vessel size categorization in nerve biopsy From “Distinctive clinical features in biopsy-proven nerve large-arteriole vasculitis and microvasculitis”

Abstract

This study underscores the different pathophysiology of nerve large-arteriole vasculitis and nerve microvasculitis: that is nerve microvasculitis is associated with greater nerve proximal nerve and root involvement, while nerve large-arteriole vasculitis typically shows watershed infarction (occurring at mid-thigh and mid-arm levels), thus manifesting as primarily distal asymmetrical neuropathies. However, these processes represent a continuum of anatomical involvement rather than entirely distinct entities. With the unclear pathomechanism, different antigens might speculatively contribute to this variation. Additionally, this study confirms the association between nerve large-arteriole vasculitis and connective tissue disorders and more systemic vasculitis whereas microvasculitis is more associated with diabetes mellitus. We plan to further publish findings on clinical outcomes and pathological distinctions between the two conditions.