case_images: PMC5438016_01
case_images: Renal biopsy histology demonstrating focal segmental proliferative and necrotizing glomerulonephritis. A: Glomerulus with segmental proliferation and crescent (hematoxylin-eosin stain, x200). B: Glomerulus with segmental necrosis and crescent (Jones silver stain, x200). C: Glomerulus with cellular crescent and interstitial fibrosis (Masson trichrome stain, x200). D: Two glomeruli with fibro-cellular lesions and scarring indicative of chronicity (hematoxylin-eosin stain, x200).
case_images: CNCS-5-032-01.jpg
case_images: PMC5438016_01_CNCS-5-032-01.jpg
case_images: Figure1
case_images: A low C3 (0.5 g/L) and C4 (0.07 g/L) and strongly positive PR3-ANCA (> 8.0 AI) with a negative p-ANCA prompted renal biopsy that revealed focal segmental proliferative and necrotizing glomerulonephritis affecting > 50% of glomeruli with cellular and fibrocellular crescents and some segmental sclerosis (Figure 1), indicative of chronicity.
case_images: Part of glomerulus with focal fusion of foot processes (arrow) and absence of immune complexes (electron microscopy, x8,000).
case_images: CNCS-5-032-02.jpg
case_images: PMC5438016_01_CNCS-5-032-02.jpg
case_images: Figure2
case_images: Immunofluorescence and electron microscopy demonstrated a paucity of any significant immune complexes (Figure 2), and, given the severity and extent of necrotizing lesions, a diagnosis of pauci-immune GN consistent with ANCA vasculitis was made. 