Nierenbeteiligung bei systemischen Vaskulitiden

Abstract

The systemic vasculitides are a heterogenous group of autoimmune disorders, characterised by vessel wall inflammation leading to tissue damage and consecutive loss of function in the dependent organ systems. Vasculitides are classified by aetiological, morphological and immunological criteria. Primary and secundary vasculitis are distinguished diseases and they are categorised according to different sizes of the involved vessels into small, medium and large vessel vasculitis. Immunologically important are 2 different types of vasculitis, immune complex-mediated and pauci immune vasculitis. Renal involvement with rapid progressive glomerulonephritis (RPGN) is a life-threatening complication and needs to be diagnosed and treated immediately. Necrotising crescentic glomerulonephritis is histologically characteristic for ANCA-associated vasculitis. There are evidence-based protocols for induction and maintenance therapy. Combined treatment with steroids and cyclophosphamide is mandatory for critical organ involvement. B-cell-depleting therapy with rituximab is an efficient alternative. Azathioprine, methotrexate and leflunomide are recommended for maintaining remission. Infections, related to therapy or disease, are of particular clinical interest, because they are responsible for increased mortality during the early course of disease. Furthermore, gonadal insufficiency after cyclophosphamide therapy and steroid-induced osteoporosis should be prevented. Immune complex-mediated vasculitis could also cause renal involvement, although the course of glomerulonephritis is less agressive. Kryoglobulinaemic vasculitis is often associated with active hepatitis C infection and remission could be achieved by elimination of virus with interferon alpha. Renal involvement in large vessel vasculitis is mainly attributed to ischaemia and consecutive renal hypertension.