Lupus nephritis: an update

Lupus nephritis (LN) is an inflammatory condition of the kidneys that encompasses various patterns of renal disease including glomerular and tubulointerstitial pathology. It is a major predictor of poor prognosis in patients with systemic lupus erythematosus (SLE). Genetic factors, including several predisposing loci, and environmental factors, such as EBV and ultraviolet light, have been implicated in the pathogenesis. It carries a high morbidity and mortality if left untreated. Renal biopsy findings are utilized to guide treatment. Optimizing risk factors such as proteinuria and hypertension with renin-angiotensin receptor blockade is crucial. Immunosuppressive therapy is recommended for patients with focal or diffuse proliferative lupus nephritis (Class III or IV) disease, and certain patients with membranous LN (Class V) disease. Over the past decade, immunosuppressive therapies have significantly improved long-term outcomes, but the optimal therapy for LN remains to be elucidated. Cyclophosphamide-based regimens, given concomitantly with corticosteroids, have improved survival significantly. Even though many patients achieve remission, the risk of relapse remains considerably high. Other treatments include hydroxychloroquine, mycofenolate mofetil, and biologic therapies such as Belimumab, Rituximab, and Abatacept. In this paper, we provide a review of LN, including pathogenesis, classification, and clinical manifestations. We will focus, though, on discussion of the established as well as emerging therapies for patients with proliferative and membranous lupus nephritis.