Serum cystatin C and microalbuminuria in burn patients with acute kidney injury.

Abstract

This study was aimed at evaluating the effectiveness of serum cystatin C and microalbuminuria as diagnostic markers for acute kidney injury (AKI) in major burn patients. Major burn adult patients admitted to the burn intensive care unit within 24 h from the onset of injury were enrolled. Serum cystatin C and microalbuminuria (albumin-creatinine ratio, ACR) were obtained at postburn days 1, 3, 7, 14, 21 and 28. The patients were divided into two groups of the AKI group and the nonacute kidney injury group. A total of 97 patients were enrolled in this study. Acute kidney injury was diagnosed in 40 patients (41.2%) at postburn day 17.3 ± 7.9. The area under the curve of the receiver operating characteristic curve for serum cystatin C was 0.808 (95% CI, 0.711-0.905, P < 0.001) at postburn day 7 and 0.908 (95% CI, 0.843-0.973, P < 0.001) at postburn day 14. The results were 0.610 (95% CI, 0.497-0.724, P = 0.069) for ACR at postburn day 7 and 0.694 (95% CI, 0.589-0.798, P = 0.001) at postburn day 14. The optimal cut-off value of serum cystatin C at postburn day 14 and ACR at postburn day 14 were 0.85 mg/L (sensitivity, 89.5%; specificity, 82.5%) and 41.51 mg/g cre (sensitivity, 60.5%; specificity, 61.4%), respectively. Serum cystatin C at postburn day 14 was the only significant factor in relation to AKI. Serum cystatin C is a valuable diagnostic marker, whereas microalbuminuria is a relatively less significant marker for AKI in major burn patients.