Diagnostic value of serum cystatin C in the PICU children with septic acute kidney injury

Abstract

Objective To evaluate the early diagnosis value of serum cystatin C in the pediatric intensive care unit (PICU) children with septic acute kidney injury. Methods A total of 196 children in PICU confirmed with sepsis in Hunan Province Children's Hospital was enrolled in this study. Patients were divided into acute kidney injury (AKI) and non-AKI group according to whether accompanied with acute kidney injury. The serum cystatin C and serum creatinine were collected in 2 h, 48 h, and 96 h after admission, and the clinical data were collected. The serum Cys C was drawn in receiver operating characteristic (ROC) curve. The sensitivity and specificity of Cys C were evaluated in diagnosis of septic AKI. Results The incidence of septic AKI was 35.20%, higher Cys C levels were risk factors for the onset of AKI, and OR was 26.218 (95% CI: 6.235~110.232). In AKI group, the serum Cys C level in 2 hours after admission was (2.05±0.90)mg/L, which was higher than 48 hours (1.72±0.72)mg/L and 96 hours (1.62±0.95)mg/L(Z=2.169, P=0.030; Z=2.789, P=0.005). In the septic AKI group, cystatin C and creatinine were positive correlation (r=0.582, P=0.000). The area under the ROC curve at 2 hours after admission for serum cystatin C in diagnosis of AKI was 0.831. A cutoff point of 1.325 mg/L for 2 hours after admission was identified for cystatin C in the diagnosis of septic AKI, with a sensitivity of 87.1% and specificity of 78.9%. Conclusions Higher level of Cys C was risk factor for the onset of AKI. Compare to creatinine, cystatin C was earlier increased in children with septic AKI and positively correlated with it. It might be a biomarker for early diagnosis of septic AKI in PICU critical ill children. Key words: Cysteine proteinase inhibitors/BL; Sepsis/BL/CO/DI; Kidney/IN; Intensive care units, pediatric