Acute kidney injury network criteria as a predictor of hospital mortality in cirrhotic patients with ascites.

BACKGROUND: Acute kidney injury (AKI) is frequent in cirrhotic patients but its best definition is unclear. Recently, the Acute Kidney Injury Network (AKIN) proposed criteria to define AKI. The aims of this study were to apply AKIN criteria to cirrhotic patients with ascites and to evaluate its association to hospital mortality. STUDY: In this retrospective study, cirrhotic patients with ascites admitted to a university hospital in Brazil between November 2003 and December 2007 were included. AKIN criteria were applied in the first 48 hours of hospitalization, considering 2 values of creatinine in this period. Association of AKI at admission and hospital mortality was analyzed.
RESULTS: Of the 198 patients in the study, 91 (46%) presented AKI at hospital admission. Overall hospital mortality was 40.4%. Patients without AKI had a hospital mortality rate of 29.9%, whereas the same rate for patients with this complication was 52.7% (odds ratio=2.6; 95% confidence interval, 1.5-4.7; P=0.001). In a logistic regression analysis, 4 variables were independently associated to hospital mortality: infection, hepatic encephalopathy, Child score, and AKI. A receiver operating characteristic curve analysis revealed that the variation in creatinine proposed by AKIN had the best combination of sensitivity and specificity in relation to hospital mortality.
CONCLUSIONS: In cirrhotic patients with ascites, prevalence of AKI at hospital admission is high. Patients with renal dysfunction defined by AKIN have significant higher hospital mortality. AKIN criteria are useful in cirrhotic patients with ascites, as it identifies earlier patients with worse prognosis.