ABSTRACT
Objective We aimed to investigate the clinical values of combination of blood creatinine and cystatin C for acute kidney injury(AKI)diagnosi. Methods Total 7 627 patients were studied retrospectively. The AKI was classified by creatinine or cystatin C according to the Kidney Disease:Improving Global Outcomes criteria. Results The maximum levels of cystatin C and creatinine were correlated(Spearman′s rank coefficient 0.699,P < 0.001). The area under a receiver operating characteristic curve of maximum cystatin C value for pre-dicting in-hospital death was 0.761(95% confidence interval 0.693 ~ 0.828). Total 1 004 and 173 patients were classified into AKI by blood creatinine or by cystatin C(13.2% vs.2.3%,P<0.001),respectively.The total inci-dence of AKI was 14.7% diagnosed by the combination of the two markers.In multivariable logistic model,the cre-atinine negative plus cystatin C positive group was associated with a higher in-hospital death compared with the cre-atinine and cystatin C double negative group(OR 15.524,95% confidence interval 5.110 ~ 47.166,P < 0.001). Conclusion Combination of cystatin C increased sensitivity of creatinine for AKI diagnosis and facilitated to iden-tify in-hospital patients with high risk.