Abstract: Objective  To investigate the clinical value of serum protein electrophoresis (α2+β) / Alb ratio in the early screening of diabetic nephropathy and its combination with serum CysC for early diagnosis of diabetic nephropathy. Methods  According to urinary microalbumin/creatinine ratio (ACR), a total of 70  patients with type 2 diabetes were divided into normal albuminuria group and early diabetic nephropathy group with 35 cases in each group.At the same time, a total of 35 subjects for health check were selected as a  control group. The serum protein electrophoresis, estimated glomerular filtration rate (eGFR), serum CREA, α1MG, β2MG, CysC level and serum protein electrophoresis (α2+β) /Alb ratio were compared among  experimental groups, and the diagnostic value of each index was evaluated by ROC curve. Results  With the increase of ACR level in diabetic patients, serum protein electrophoresis changed significantly, there were significant differences among experient groups in (α2+β)/ Alb ratio (P<0.01). ROC curve analysis showed that the AUC of (α2+β)/Alb ratio in differentiating microalbuminuria, controls and normal albuminuria was 0.860 with the sensitivity of  91.4%  and the specificity of 75.7% in the optimal cutoff value of  0.32, superior to eGFR, CREA, α1MG, β2MG and CysC; The AUC of the combination of (α2+β)/Alb and CysC for diagnosis of early stage of diabetic kidney disease was 0.911  with the sensitivity of  91.4% and the specificity of  82.9%.Conclusion  The serum protein components of diabetic nephropathy changed in the early stage. The  (α2+β)/Alb  ratio has certain clinical significance for early screening of diabetic nephropathy, and its combination with CysC is helpful in the early diagnosis of diabetic nephropathy.

Key words: diabetic nephropathies, blood protein electrophoresis, early diagnosis