Urinary cystatin C is diagnostic of acute kidney injury and sepsis, and predicts mortality in the intensive care unit.
Crit Care. 2010 May 12;14(3):R85
Authors: Nejat M, Pickering JW, Walker RJ, Westhuyzen J, Shaw GM, Frampton CM, Endre ZH
ABSTRACT: INTRODUCTION: To evaluate the utility of urinary cystatin C (uCysC) as a diagnostic marker of Acute Kidney Injury (AKI) and sepsis, and predictor of mortality in critically ill patients. METHODS: A two-centre, prospective AKI observational study and post-hoc sepsis subgroup analysis of four hundred and forty four general intensive care unit (ICU) patients. uCysC and plasma creatinine were measured at entry to ICU. AKI was defined as a 50% or 0.3mg/dl increase in plasma creatinine above baseline. Sepsis was defined clinically. Mortality data was collected to 30 days. The diagnostic and predictive performances of uCysC were assessed from the Area Under the Receiver Operator Characteristic Curve (AUC) and the odds ratio (OR). Multivariate logistic regression was used to adjust for covariates. RESULTS: Eighty-one patients (18%) had sepsis, 198 (45%) AKI, and 64 (14%) died within 30 days. AUCs for diagnosis using uCysC were: sepsis 0.80, (95% Confidence Interval (CI):0.74 to 0.87), AKI 0.70 (CI:0.64 to 0.75), and death within 30 days, 0.64 (CI:0.56 to 0.72). Following adjustment for covariates, uCysC remained independently associated with sepsis, AKI and mortality with odds ratios (CI) of 3.43 (2.46 to 4.78), 1.49 (1.14 to 1.95), and 1.60 (1.16 to 2.21) respectively. Concentrations of uCysC were significantly higher in the presence of sepsis (P < 0.0001) or AKI (P < 0.0001). There was no interaction between sepsis and AKI on the uCysC concentrations (P = 0.53). CONCLUSIONS: Urinary cystatin C was independently associated with AKI, sepsis, and death within 30 days. Trial registration: Australian New Zealand Clinical Trials Registry ACTRN012606000032550.
PMID: 20459852 [PubMed - as supplied by publisher]