Lupus nephropathy and vasculitis

Multi-system autoimmune diseases, including systemic lupus erythematosus (SLE) and vasculitis, are inflammatory conditions of unknown cause. Renal involvement can occur in a variety of forms and usually represents a severe disease manifestation. SLE is complicated by renal involvement (lupus nephritis) in over one-third of patients. Small vessel vasculitides, including anti-neutrophil cytoplasmic antibody-associated and anti-glomerular basement membrane disease, also frequently affect the kidneys causing a rapidly progressive glomerulonephritis (RPGN). Histologically, this manifests as a necrotizing, crescentic glomerulonephritis. This is potentially reversible but, if left untreated, would generally result in end-stage renal failure and death within days to weeks. A crescentic glomerulonephritis may also be seen in SLE, but this is not the typical pattern of lupus nephritis, which is usually characterized by immune complex deposition causing a diffuse, proliferative glomerulonephritis. Lupus nephritis and renal vasculitis are the most frequent causes of renal failure in multi-system autoimmunity.