title: Cell interposition in glomerular capillary walls in cryoglobulinemic glomerulonephritis (CRYGN). Ultrastructural investigation of 23 cases.
abstract: The present report describes ultrastructural findings on twenty-three cases of CRYGN showing membranoproliferative pattern under light microscopy. Attention was paid to the presence of double contoured peripheral basement membranes and to the characteristics of the interposed cells. The latter, according to the well known characteristics of membranoproliferative GN, are thought to be mesangial in nature. In fact, mesangial cells were found in 8 cases only, always associated with monocytes. Only monocytes were recorded in 12 cases, whereas in other 3 cases double contours were not connected to cell interposition. Despite similarities under light microscopy, CRYGN is therefore rather different from idiopathic membranoproliferative GN because of the prevalence of exudative changes, mainly due to monocyte infiltration, over proliferative lesions.
mesh_terms: D003449:Cryoglobulinemia / Q000473:pathology*; D005921:Glomerulonephritis / Q000473:pathology*; D006801:Humans; D007678:Kidney Glomerulus / Q000648:ultrastructure*; D008854:Microscopy, Electron