Membranoproliferative glomerulonephritis

Membranoproliferative glomerulonephritis (MPGN, also known as mesangiocapillary glomerulonephritis) is a designation given to a very heterogeneous collection of disorders that manifest by light microscopy both mesangial hyper-cellularity and proliferation accompanied by broadening of the peripheral capillary loops (Holley and Donadio, 1994; Glassock et al., 1995; Strife and West, 2001; Glassock, 2008) due to reduplication of the glomerular capillary basement membrane (known as ‘double-contour’). In many instances, these broadened capillary loops also display prominent interposition of cells between the layers of the basement membrane and/or subendothelial or intra-membranous electron-dense deposits that may be accompanied by fragmentation or distortion of the basement membrane itself. The disorders encompassed by this definition also frequently display persistent reduction in serum complement levels (West et al., 1965).