Pathology of Neuropsychiatric Systemic Lupus Erythematosus
Small vessel non inflammatory vasculopathy, microvessel occlusion, multifocal microinfarcts, microhaemorrhages and cortical atrophy were most frequently observed pathological changes in NPSLE. Although vasculitis in the brain is rather uncommon, it might be detected in about 10% of patients with NPSLE. It has been revealed that activation of complement appears to play an important role in the development of microvasculopathy in NPSLE. Autoantibodies, including anti phospholipid antibodies, causing direct injury of endothelial cells would be involved in the deposition of complements. Since anti NMDA receptor NR2 antibodies have been demonstrated to react with endothelial cells to induce the production of inflammatory cytokines, it is possible that these antibodies might also result in the microvascular changes in the brain. Recent studies have shed light on the roles of microglia in relation with type I interferons in the pathogenesis of NPSLE.