title: Pathological implications of linear immunoglobulin G staining on the glomerular capillary walls in a case of infection-related glomerulonephritis.
abstract: We report a 32-year-old man with nephrotic syndrome and preceding symptom of infection. He had renal insufficiency, hypocomplementemia, and elevated titer of anti-streptolysin O. Renal biopsy showed mesangial hypercellularity and focal segmental endocapillary hypercellularity with double contour of the glomerular basement membrane (GBM). Immunofluorescence study showed granular C3 staining on the mesangial areas and glomerular capillary walls (GCWs) and linear immunoglobulin G (IgG) staining on GCWs. Electron microscopy revealed sporadic subepithelial humps, discontinuous small and thin deposits in the endothelial side of the GBM and mesangial deposits. He was diagnosed with infection-related glomerulonephritis (IRGN) with the striking finding of linear IgG staining, which is unusual in IRGN. The patient did not have diabetes mellitus or anti-GBM disease. The patient's serum seemed not to contain IgG, which can bind to GCW. He showed normalization of complement within two months after relief from infection symptoms and a trend toward improvement in proteinuria, hematuria and renal function over 14 months. We discuss the possible mechanisms of linear IgG staining in our case based on clinical and experimental studies on IRGN with cationic bacterial protein as antigen.
authors.affiliation: Department of Internal Medicine, Teikyo University School of Medicine, Tokyo, Japan.|Central Laboratory, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Yoshihide
authors.identifier: http://orcid.org/0000-0003-2803-9161
authors.initials: Y
authors.lastname: Fujigaki
authors.affiliation: Department of Internal Medicine, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Kawamorita
authors.affiliation: Department of Internal Medicine, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Yamaguchi
authors.affiliation: Department of Internal Medicine, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Arai
authors.affiliation: Department of Internal Medicine, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Yoshifuru
authors.initials: Y
authors.lastname: Tamura
authors.affiliation: Department of Internal Medicine, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Tatsuru
authors.initials: T
authors.lastname: Ota
authors.affiliation: Department of Internal Medicine, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Shibata
authors.affiliation: Department of Pathology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Fukuo
authors.initials: F
authors.lastname: Kondo
authors.affiliation: Department of Pathology, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Yamaguchi
authors.affiliation: Department of Internal Medicine, Teikyo University School of Medicine, Tokyo, Japan.
authors.forename: Shunya
authors.initials: S
authors.lastname: Uchida
mesh_terms: D000328:Adult; D002196:Capillaries / Q000276:immunology / Q000473:pathology; D005455:Fluorescent Antibody Technique; D005921:Glomerulonephritis / Q000276:immunology* / Q000473:pathology*; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D007678:Kidney Glomerulus / Q000276:immunology* / Q000473:pathology*; D008297:Male
chemical_list: D007074:Immunoglobulin G
keywords: cationic protein; hump formation; infection-related glomerulonephritis; linear IgG staining