Elevated Serum Levels of Carbohydrate Antigen 72–4 in Diabetic Kidney Disease

The aim of this study was to determine whether carbohydrate antigen 72–4 (CA72–4) is elevated in diabetic kidney disease (DKD), and examine the association between urinary albumin-to-creatinine ratio (UACR) and CA72–4 in patients with type 2 diabetes mellitus (T2DM). Non-dialysis patients with T2DM (n=296) and 90 healthy controls were recruited in this study. CA72–4 level was measured by electrochemiluminescence immunoassay. DKD was defined as UACR≥ 30 mg/g in the absence of a urinary infection or other renal diseases. We found that patients with DKD had significantly higher serum CA72–4 levels compared to those with normoalbuminuria and healthy controls. Positive rates of CA72–4 increased gradually and markedly from normoalbuminuria to microalbuminuria and to macroalbuminuria in diabetic patients (7.5, 11.2, and 17.4%, respectively; P for trend< 0.05). CA72–4 also showed a positive correlation with UACR (r=0.288, P< 0.01). Logistic regression analysis revealed the association of increased UACR with an increased odds ratio of elevation of CA72–4 levels (P for trend< 0.05) after multivariable adjustment. In conclusion, serum levels of CA72–4 increase abnormally with the increase in urinary albumin excretion, which affects the specificity of diagnosis of malignancies. An appropriate interpretation of CA72–4 is essential to prevent unnecessary and even hazardous diagnostic procedures in patients with T2DM.