The Correlation Between Serum Immunoglobulin,Complement C3,C4 Levels And Diabetic Nephropathy

Purpose:The correlation between serum immunoglobulin,complement C3,C4 levels and diabetic nephropathy was retrospectively analyzed.Methods:We collected 63 patients with definite diagnosis of diabetic nephropathy(DN)received renal biopsy in the Department of Nephrology of the First Hospital of Jilin University from 2011 to 2020,and 37 patients diagnosed with diabetic mellitus(DM)without proteinuria in the Department of Endocrinology during the same period and 30 healthy subjects were selected as controls.According to whether the patient had DM o DN,they were divided into three groups:Normal control group(N=30),DM group(N=37)and DN group(N=63),According to the pathological results of renal biopsy,the DN patients were divided into three subgroups;early DN group(N=8),diffuse DN group(N=28)and nodular DN group(N=27).The clinical and pathological data of the above patients were collected,and the results were statistically analyzed to observe the relationship between serum immunoglobulin(Ig),complement 3(C3)and complement 4(C4)levels and the progression of diabetic nephropathy.Results:(1)Clinical characteristics and biochemical indexes of the control group,DM group and DN group were analyzed,the result shows:1)The level of serum IgG and C3 levels in DN group were lower than that in DM group and Normal control group(P<0.05).The level of serum C4 level in DN group were higher than that in DM group(P<0.05).The level of serum IgM level in DN group and DM group were lower than that in Normal control group(P<0.05).2)C3(OR:0.046,95%CI:0.007-0.315,P<0.05),serum albumin(OR:0.744,95%CI:0.641-0.863,P<0.05),IgG(OR:0.737,95%CI:0.544-0.999,P<0.05)were the predictors of DN,and serum albumin and IgG were independent predictors of DN.(2)The clinical characteristics and biochemical indexes of each group were analyzed.The results showed that estimated glomerular filtration rate(eGFR)in the three groups decreased successively,and the level of C3 in the nodular DN group was significantly lower than that in the early DN group.(3)After the analysis of the correlation of serum immunoglobulin,C3 and C4,and renal function in DN patients,it was found that serum IgA was negatively correlated with creatinine and 24-hour urinary microalbumin in DN.IgG were negatively correlated with creatinine,24-hour urinary microalbumin and albumin creatinie ratio(ACR).Serum C3 was negatively correlated with creatinine and positively correlated with eGFR.Conclusions:(1)Serum IgG and C3 are predictors of DN and plays an important role in the occurrence of DN.(2)Serum IgG and C3 are related to the progression of DN.With the decrease of renal function,the levels of serum IgG and C3 decrease,suggesting that immunoglobulin and complement system may be involved in the progression of DN.