The Study On The Relationship Between Serum And Urine Transferrin Levels And Diabetic Nephropathy

Objective To explore the relationship between serum and urine Tf levels and diabetic nephropathy（DN）,and explore new biological markers for clinical diagnosis and treatment of DN.Methods（1）170 patients with T2DM in the Endocrinology Department of the First Hospital of Lanzhou University were selected as the study subjects from October 2019to December 2020.At the same time,30 health examinees were selected as the control group in the physical examination center of our hospital.According to the severity of DN,patients with T2DM were divided into normal albuminuria group,microalbuminuria group,macroalbuminuria group and renal insufficiency group Pearson correlation analysis and logistic regression analysis of influencing factors of serum Tf level.（2）In Pub Med,Embase,Web of Science,Cochrane,CBM,CNKI and Wanfang database,we searched the database from October 2021 to about the level of serum transferrin and diabetic nephropathy.Or related literature on the diagnostic value of urine Tf in DN patients,meta-disc 1.4 and Stata 14.0 software were used to evaluate the correlation between serum Tf level and DN,as well as the diagnostic value of urine Tf level on DN through meta-analysis.Results（1）T2DM combined with normal proteinuria group（2.32±0.26）g/L,Serum Tf levels in microproteinuria group（2.13±0.32）g/L,macroproteinuria group（1.93±0.31）g/L and renal insufficiency group（1.74±0.33）g/L were significantly lower than those in normal control group（2.64±0.39）g/L.The serum Tf level in T2DM combined with microalbuminuria group was significantly lower than that in normal proteinuria group.The serum Tf level in T2DM with macroalbuminuria and renal insufficiency group was significantly lower than that in microalbuminuria group（2）T2DM patients were divided into 4 groups according to e GFR level.The serum Tf levels（2.06±0.34 g/L）and（1.82±0.41 g/L）in mildly decreased filtration function group（e GFR=60-89m L/min/1.73m~2）and moderate-severe decreased filtration function group（e GFR≤60m L/min/1.73m~2）were significantly lower than those in normal filtration function group（e GFR=90-120m L/min/1.73m~2）Tf level[（2.25±0.34）g/L,P<0.05].（3）Serum Tf level was negatively correlated with UAER and creatinine levels in T2DM patients[r=-0.479,P<0.001;r=-0.249,P=0.001].Positive correlation with e GFR level（r=0.317,P<0.001）.Multiple regression analysis showed that serum Tf level was negatively correlated with UAER（B=-0.001,P<0.001）.Ordered logistic regression analysis suggested that serum Tf level was an independent protective factor for the occurrence of nephropathy in T2DM patients（OR=0.029,P<0.001）.（4）A total of 9 literatures on the relationship between serum Tf level and DN were included.Meta-analysis showed that the serum Tf level in microproteinuria group was lower than that in normal albuminuria group[SMD=-0.61,95%CI（-0.99,-0.23）,P<0.05].The serum Tf level in macroalbuminuria group was lower than that in microalbuminuria group[SMD=-0.76,95%CI（-1.05,-0.47）,P<0.05].The serum Tf level in macroalbuminuria group was lower than in the normal albuminuria group[SMD=-1.36;95%CI（-1.76,-0.95）,P<0.05].（5）A total of 9 literatures on the diagnostic value of urine Tf level in DN were included.Meta-analysis showed that the combined sensitivity was 0.81（95%CI:0.71-0.88）,specificity was 0.89（95%CI:0.85-0.92）.The PLR was 7.31（95%CI:5.28-10.12）,the NLR was 0.22（95%CI:0.14-0.33）,and the DOR was 33.59（95%CI:17.43-64.74）.The AUC was 0.92（95%CI:0.89-0.94）.Conclusion Serum transferrin level in T2DM patients decreased gradually with the increase of urinary protein.Serum Tf was negatively correlated with the level of urinary albumin.Tf is a protective factor of diabetic nephropathy.In addition,serum and urine Tf have important clinical significance in the diagnosis of DN.