Glomerulonephritis mit MPGN-Muster und verwandte Formen

According to the latest Kidney Disease: Improving Global Outcomes (KDIGO) guidelines on glomerular diseases, rare forms of glomerulonephritis (GN) mediated by the complement system are categorized under glomerulonephritis with a membranoproliferative GN (MPGN) pattern. Insights into the pathophysiology suggest that these represent a spectrum of secondary and idiopathic diseases, transitioning between immune complex-mediated MPGN (IC-MPGN) and C3 glomerulopathy (C3G). There are many similarities regarding secondary causes, autoantibodies and genetic factors. The MPGN pattern is not exclusive but represents one of several histopathological manifestations. The pathogenetic role of light chain diseases is particularly significant for these diseases. The understanding of the pathophysiology is crucial for further diagnostics, especially for identifying secondary causes. Therefore, in addition to the primary search for secondary causes, a comprehensive analysis of the complement system, antibody screening and genetic testing should be consistently performed. Chronic damage, high proteinuria, and a demonstrably activated complement system are associated with a poor prognosis. There is still a lack of systematic interventional studies. Whenever possible, patients should be systematically registered, thoroughly evaluated and, if applicable, included in ongoing phase 3 studies on the specific blockade of the complement system.