(A) Protein patterns of the patients with diabetes and control subjects examined in this study. Shown are compiled patterns consisting of all samples from each of the four groups. The molecular mass (0.7 to 25 kD, on a logarithmic scale) is plotted against normalized migration time (17 to 47 min). Signal intensity is encoded by peak height and color. (B) Distribution of potential differential-diagnostic biomarkers for diabetes in the patients with normoalbuminuria and healthy control subjects. All statistically significant biomarkers from Supplemental Table 1 are shown. (C) Distribution of potential differential-diagnostic biomarkers for diabetic nephropathy in the different groups of patients and healthy control subjects. Shown are all statistically significant biomarkers listed in Supplemental Table 2.

(A) Protein patterns of the patients with chronic renal disease (CRD). Shown are compiled patterns consisting of samples from patients with FSGS (n = 35) IgA nephropathy (IgAN; n = 57), minimal-change disease (MCD; n = 25), and membranous glomerulonephritis (MNGN; n = 29). In comparison with Figure 1A, these compiled data show a much higher degree of similarity to the patients with macroalbuminuria than to any other group with diabetes. The molecular mass (0.7 to 25 kD, on a logarithmic scale) is plotted against normalized migration time (17 to 47 min). Signal intensity is encoded by peak height and color. (B) Distribution of potential differential-diagnostic biomarkers for diabetic nephropathy(DN) in all patients with macroalbuminuria (DN group) and all control subjects with (CRD group) used in the study. All 37 statistically significant biomarkers from Table 2 are shown. (C) Receiver operating characteristic analysis of the performance of the differential diagnostic biomarker pattern for DN. (Left) Data from the training set of 44 case patients and 104 control subjects (sensitivity of 95.5% and specificity of 94.2%; area under the curve was 0.971). (Right) Data from validating the masked test set consisting of 64 samples (81.0% sensitivity and 90.7% specificity; area under the curve was 0.856).