Association Study Of Relationship Between Mesangial Immune Deposition And Clinicopathology In IgA Nephropathy

Objective: To investigate the relationship between mesangial C3, sole IgM deposition, IgGand IgM co-deposition and the clinicopathological features in IgA nephropathy.Methods:170patients with primary IgA nephropathy were assigned into three groups (C3negative group, C3positive group and C3strongly positive group) according to the intensityof C3deposition in glomerular mesangium. And their pathological and clinical features werecompared between groups.152patients with C3strongly positive and positive were furtherassigned into three groups, namely simplex IgA deposition group (IgA group), simplex IgMdeposition(IgM group) and multi-immunoglobulin co-deposition group (IgG and IgMco-deposition group). The pathological and clinical features were compared between groups.Results:1. eGFR and serum C3were significantly correlated with the intensity of C3deposition in glomerular mesangium. The renal function degraded with the intensity of C3deposition, while the concentration of blood C3decreased(P＜0.05). Microscopic hematuria,serm IgA and24hours urine protein were not correlated with the intensity of C3deposition inglomerular mesangium（P＞0.05）.With the elevation of the intensity of mesangial C3deposition, the severity of renal tubular atrophy, renal tubular vacuolization degeneration,interstitial fibrosis, interstitial inflammatory cell infiltration, arteriolar lesions increased, andthe degree of Lee pathological grades increased（P＜0.05). capillary endothelial hyperplasia,crescent and glomerulosclerosis were not correlated with the intensity of C3deposition inglomerular mesangium（P＞0.05）.2. eGFR was correlated with the IgG and IgM co-deposition in glomerular mesangium. Thesubjects with IgG and IgM co-deposition maintains better renal function compared with IgAgroup（P＜0.05）. eGFR was not correlated with the IgM deposition in glomerular mesangium.There was not difference compared with IgA group（P＞0.05）. Diffuse proliferation wasrelated with IgG and IgM co-deposition in glomerular mesangium. The subjects with IgG andIgM co-deposition have been proved that maintain inapparent diffuse proliferation compared with IgA group（P＜0.05）. renal tubular vacuolization degeneration was related with IgMdeposition in glomerular mesangium. The subjects with IgM deposition have been proved thatmaintain inapparent renal tubular vacuolization degeneration compared with IgA group（P＜0.05）. Lee pathological grades was not correlated with IgA group,IgM group and IgG andIgM co-deposition group（P＞0.05）.Conclusions:1.With the increase of the intensity of mesangial C3deposition, thepathological lesion and renal function of IgA patients became worse. Mesangial C3deposition may be one of the key factors for the prognosis of IgA nephropathy.2. In subjects with C3strongly positive or positive, pathological lesion has showed no sign ofadvancement when the presence of IgM or IgG and IgM co-deposition, even slighter than thatof their counterparts. Our data suggested that the subjects with IgG and IgM co-depositionmaintains improved renal function. With the evidence we acquire from the study, we mayassume that IgG and IgM co-deposition may act as the protective factor in the development ofIgA nephropathy.