Cihan Heybeli1, Mehtat Unlu2, Serkan Yildiz3, Caner Çavdar3, Sulen Sarioglu2, Taner Camsari3. 1. a Department of Internal Medicine , Dokuz Eylul University School of Medicine , İzmir , Turkey . 2. b Department of Pathology , Dokuz Eylul University School of Medicine , İzmir , Turkey , and. 3. c Department of Nephrology , Dokuz Eylul University School of Medicine , İzmir , Turkey.
Abstract
BACKGROUND: In patients with IgA nephropathy (IgAN) lectin and alternative pathways of the complement can be activated. Our aim was to analyze the association of glomerular and extraglomerular C4d staining--the representative of lectin pathway-with demographic, clinical and histopathological findings in primary IgAN patients. DESIGN: Seventy-three patients were enrolled and after re-evaluation 37 of them were included in this study. Biopsies were analyzed for staining with anti-C4d primary monoclonal antibody by immunohistochemistry. Patients were classified as positive and negative groups based on their glomerular C4d deposition. Groups were compared for their baseline clinical and histopathological findings. RESULTS: Sixteen (43.2%) of 37 patients were C4d-positive. Glomerular C4d-staining was associated with more severe proteinuria (2906 mg/day vs. 1091 mg/day; p = 0.002), lower GFR (54.87 mL/min vs. 95 mL/min; p = 0.023), higher blood pressure (p = 0.022), more severe endocapillary hypercellularity (p < 0.001) and more severe tubular atrophy (p < 0.01). Mesangial IgM deposition was found to be associated with glomerular C4d staining and nephrotic range proteinuria. CONCLUSIONS: Glomerular C4d deposition was found to be associated with more unfavorable histopathological and clinical findings at the time of diagnosis. Association of mesangial IgM deposition with the activation of lectin pathway is a novel finding. Mesangial IgM deposition in our patients may reflect the genetic heterology of IgAN between diverse populations. However, since these data are about association, a cause-and-effect about IgM and IgAN cannot be proven solely with these findings.
BACKGROUND: In patients with IgA nephropathy (IgAN) lectin and alternative pathways of the complement can be activated. Our aim was to analyze the association of glomerular and extraglomerular C4d staining--the representative of lectin pathway-with demographic, clinical and histopathological findings in primary IgANpatients. DESIGN: Seventy-three patients were enrolled and after re-evaluation 37 of them were included in this study. Biopsies were analyzed for staining with anti-C4d primary monoclonal antibody by immunohistochemistry. Patients were classified as positive and negative groups based on their glomerular C4d deposition. Groups were compared for their baseline clinical and histopathological findings. RESULTS: Sixteen (43.2%) of 37 patients were C4d-positive. Glomerular C4d-staining was associated with more severe proteinuria (2906 mg/day vs. 1091 mg/day; p = 0.002), lower GFR (54.87 mL/min vs. 95 mL/min; p = 0.023), higher blood pressure (p = 0.022), more severe endocapillary hypercellularity (p < 0.001) and more severe tubular atrophy (p < 0.01). Mesangial IgM deposition was found to be associated with glomerular C4d staining and nephrotic range proteinuria. CONCLUSIONS: Glomerular C4d deposition was found to be associated with more unfavorable histopathological and clinical findings at the time of diagnosis. Association of mesangial IgM deposition with the activation of lectin pathway is a novel finding. Mesangial IgM deposition in our patients may reflect the genetic heterology of IgAN between diverse populations. However, since these data are about association, a cause-and-effect about IgM and IgAN cannot be proven solely with these findings.
Entities:
Keywords:
C4d; IgA nephropathy; IgM; complement; lectin pathway
Authors: Michael Eder; Nicolas Kozakowski; Haris Omic; Christof Aigner; Johannes Kläger; Brian Perschl; Roman Reindl-Schwaighofer; Gregor Bond; Georg A Böhmig; Željko Kikić Journal: J Nephrol Date: 2020-12-11 Impact factor: 3.902
Authors: Cinthia B Drachenberg; John C Papadimitriou; Preeti Chandra; Abdolreza Haririan; Susan Mendley; Matthew R Weir; Mario F Rubin Journal: Kidney Int Rep Date: 2019-07-30