title: Validation study of Oxford Classification of IgA Nephropathy: the significance of extracapillary hypercellularity and mesangial IgG immunostaining.
abstract: The Oxford classification (OC) of IgA Nephropathy (IgAN) identified mesangial hypercellularity (M), endocapillary hypercellularity (E), segmental glomerulosclerosis (S), and tubular atrophy/interstitial fibrosis (T) as predictors of outcome. We aimed to validate the OC and to investigate the clinical significance of extracapillary hypercellularity and IgG immunostaining. We examined the renal outcome at December 31, 2014, of 121 adult patients with biopsy proven primary IgAN between 2003 and 2013. The primary endpoint was doubling of serum creatinine or renal replacement therapy initiation. The mean observation period was 59.7 months. Thirty-one percent of the patients presented with a grade of extracapillary hypercellularity. In comparison with the group with no crescents, they had higher grade of inflammation, lower eGFR and increased proteinuria. There were no differences between the IgA and IgA&IgG immunostaining groups regarding the disease progression risk factors. Mean kidney survival time for the entire cohort was 10.6 (9.1, 12.0) years. In the Cox regression model, the independent predictors of decreased renal survival were eGFR at time of biopsy, S1 and the presence of crescents. Our study showed that extracapillary proliferation and S1 had the greatest importance in establishing the renal prognosis of patients with IgAN.
authors.affiliation: Nephrology Department, "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania.|"Dr Carol Davila" Teaching Hospital of Nephrology, Bucharest, Romania.|Romanian Renal Registry.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Ştefan
authors.affiliation: Nephrology Department, "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania.|Center of Internal Medicine-Nephrology, Fundeni Clinical Institute, Bucharest, Romania.
authors.forename: Gener
authors.initials: G
authors.lastname: Ismail
authors.affiliation: Nephrology Department, "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania.|"Dr Carol Davila" Teaching Hospital of Nephrology, Bucharest, Romania.
authors.forename: Simona
authors.initials: S
authors.lastname: Stancu
authors.affiliation: Nephrology Department, "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania.|"Dr Carol Davila" Teaching Hospital of Nephrology, Bucharest, Romania.
authors.forename: Adrian
authors.initials: A
authors.lastname: Zugravu
authors.affiliation: Nephrology Department, "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania.|Center of Internal Medicine-Nephrology, Fundeni Clinical Institute, Bucharest, Romania.
authors.forename: Andreea
authors.initials: A
authors.lastname: Andronesi
authors.affiliation: "Dr Carol Davila" Teaching Hospital of Nephrology, Bucharest, Romania.
authors.forename: Eugen
authors.initials: E
authors.lastname: Mandache
authors.affiliation: Nephrology Department, "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania.|"Dr Carol Davila" Teaching Hospital of Nephrology, Bucharest, Romania.|Romanian Renal Registry.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Mircescu
mesh_terms: D000328:Adult; D015331:Cohort Studies; D005260:Female; D005455:Fluorescent Antibody Technique; D005919:Glomerular Filtration Rate; D005920:Glomerular Mesangium / Q000276:immunology* / Q000473:pathology; D005922:Glomerulonephritis, IGA / Q000145:classification* / Q000276:immunology / Q000473:pathology*; D006801:Humans; D007070:Immunoglobulin A / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: D007070:Immunoglobulin A; D007074:Immunoglobulin G
keywords: IgA Nephropathy; IgG deposits; Oxford classification; crescents; immunofluorescence; kidney survival