To analyze the differences of biochemical and immunological indicators in gender or Lee′s classification of IgA nephropathy (IgAN) to provide laboratory evidence for clinical diagnosis and treatment of IgAN.

Retrospective cohort study. The information of biochemical and immunological indicators of 213 in-hospital patients which were admitted in Chinese PLA General Hospital in June to December, 2012. The data were collected and analyzed with t-test, non-parameter analysis, Pearson correlation analysis, ROC curves analysis and Logistic regression analysis according to gender or Lee′s classification (Lee′s≤3 group and Lee′s>3 group).

In this study, the average age and sex ratio of patients with IgAN was (35.0±10.6)years old and 2.04∶1.00. T-test and non-parameter analysis indicated homocysteine(HCY), immunoglobulin E (IgE), immunoglobulin M (IgM), prealbumin (PA), ceruloplasmin (CP), α1-acidoglycoprotein(α1-AGP), albumin (Alb), α2-globulin(α2-G) and γ-globulin(γ-G) had significant difference in gender (P<0.05). And cystantin-C (CYS-C), HCY, complement 4(C4), β2-microglobulin(β2-MG), PA, α1-AGP, α1-globulin(α1-G), immunoglobulin G (IgG), IgM and transferrin (TF) had significantly different in Lee′s classification (P<0.05). ROC curves analysis showed that the areas under curves of CYS-C and β2-MG were 0.891 and 0.839 respectively; the sensitivity was 90.2% and specificity was 75.3% when cutoff value of CYS-C was 1.56 mg/L; the sensitivity was 80.3% and specificity was 78.8% when cutoff value of β2-MG was 0.275 mg/dl. Logistic regression analysis showed that CYS-C (OR: 31.380, 95% CI: 10.808-91.113, P=0.000) and HCY (OR: 1.035, 95% CI: 1.002-1.069, P=0.040) were introduced into the model after twice variable selections. ROC curve of CYS-C combined with HCY for classifying Lee′s classification showed that the sensitivity, specificity, Jorden index and AUC were 0.843, 0.862, 0.705 and 0.894 (P=0.000), respectively.

CYS-C, β2-MG, PA and HCY were valuable indicators for Lee′s classification. CYS-C and β2-MG had high correlation with Lee′s classification, which indicated that these two tests were related to the severity of IgAN. CYS-C combined with HCY could improve the diagnostic efficiency of IgAN Lee′s classification. Combination of biochemical and immunological indicators could improve the accuracy of Lee′s classification and provide effective laboratory evidence for clinical treatment of IgAN.(Chin J Lab Med, 2016, 39: 695-700)

Glomerulonephritis, IGA; Cystatin C; beta 2-Microglobulin; Prealbumin; Homocysteine