[Lupusnephritis].

During the course of systemic lupus erythematosus (SLE) 30-90% of patients develop a renal manifestation which has proven to be decisive for morbidity and mortality. Histologically six different classes have been described leading to different treatment strategies. In mesangial proliferative lupus nephritis (class II) extrarenal manifestations determine the immunosuppressive treatment. However, in class III and IV (focal or diffuse proliferative manifestation) cyclophosphamide or possibly mycophenolate mofetil (MMF) as an alternative is necessary. In membranous lupus nephritis (class V) dual renin-angiotensin aldosterone (RAAS) blockade is most important. With class I (minimal mesangial lupus nephritis) and class VI (sclerosis) no immunosuppressive therapy is needed. New treatment options concentrate on B-cell depletion, inhibition of cytokines and co-stimulatory molecules. Recently, for the first time in SLE, a monoclonal antibody (belimumab) against B lymphocyte-stimulating factor (Blys) has been approved for treatment in combination with standard therapy.