Membranoproliferative GlomerulonephritisA Disease or a Pattern of Injury?

Abstract

Introduction: Membranoproliferative Glomerulonephritis (MPGN) is a pattern of glomerular injury resulting from wide range of diseases sharing a common pathogenesis and thus, presented with large spectrum of clinical presentation starting from slowly progressive subnephrotic range proteinuria to nephritic syndrome and Rapidly Progressive Glomerulonephritis (RPGN). Aim: The aim of the study was to do reanalysis of the aetiological classification of MPGN and its prognostic outcomes. Materials and Methods: A retrospective, cohort study was conducted including the patients of all age groups with MPGN pattern of injury, from February, 2018 to August, 2018 at a Tertiary Healthcare Centre of West Bengal, India. All specimens were examined by two nephropathologists at the institute using both light microscope and immunofluorescence microscope. Haematoxylin and Eosin (H&E), Periodic AcidSchiff (PAS), silver methanamine, Masson’s Trichrome (MT) stained smears were prepared for light microscopy. Specimens for immunofluorescence microscopy were stained using Fluorescein Isothiocyanate (FITC) conjugated polyclonal rabbit anti-sera against human IgG, IgM, IgA, C3, C1q, kappa, lambda. Correlations were evaluated using Spearman’s rank correlation. A p<0.05 was considered as statistically significant. GRAPHPAD PRISM 5 was used for statistical analysis. Results: From a total of 47 cases, 41 cases in immunoglobulin associated group, 4 cases in C3 nephropathy group and 2 cases in pauci-immune group were found. Autoimmune diseases had the strongest association followed by infections and dysproteinemia. Severity and chronicity parameters were more prevalent in the immunoglobulin positive group. The pauci-immune group showed maximum vascular involvement, indicating it to arise from a vascular pathology. Conclusion: Membranoproliferative Glomerulonephritis is not a single disease entity instead this pattern of injury could be seen in a variety of diseased condition.

Keywords

• immunofluorescence microscopy
• light microscopy
• nephritic syndrome