Fig. 1.

Two autoimmune pathogenic pathways for NPSLE

Ischaemic injury involving both large- and small-calibre vessels mediated by aPL antibodies, immune complexes and complement activation. Injury due to inflammation in which enhanced permeability of the BBB in association with antineuronal antibodies and formation of immune complexes lead to production of pro-inflammatory mediators and microglial activation. Both pathways may result in either focal or diffuse NP manifestations for which other non-SLE causes must be considered. pDC: plasmacytoid dendritic cell; dys: dysfunction.