[Lupus nephritis].

Lupus nephritis (LN) is the most frequent and one of the most severe organ manifestations of systemic lupus erythematosus. The central pathogenetic mechanism is characterized by the loss of immune tolerance against autoantigens of the cell nucleus, which can lead to renal inflammation via the formation of nuclear autoantibodies. The clinical manifestations of LN encompass nephritic syndrome with the special form of rapidly progressive glomerulonephritis, nephrotic syndrome and thrombotic microangiopathy. The diagnostic procedures consist of renal function and urine analysis as well as the determination of serum autoantibody profiles and complement components. An early renal biopsy enables a differentiation between the prognostically different forms of LN. In addition to supportive measures, a differentiated immunosuppressive treatment is the main approach for prognostically unfavorable forms. Important components are corticosteroids, cyclophosphamide and mycophenolate mofetil for induction treatment. Currently investigated treatment principles include next generation calcineurin inhibitors and anti-B cell treatment.