Background and aims: Spontaneous bacterial peritonitis (SBP) often triggers acute-on-chronic liver failure (ACLF). Acute kidney injury (AKI) is frequent and correlates with higher mortality in such cases. The aim of this study is to evaluate the Acute Kidney Injury Network (AKIN) criteria in the prediction of death in cirrhotic patients after an episode of SBP.
Material and methods: Forty-six cirrhotic patients with SBP were included in a cohort study. Renal injury was estimated by AKIN criteria (grades 1, 2 or 3) to examine the association between AKI severity and mortality. Patients were followed-up for a mean of 13.22 months. Kaplan-Meier survival curve and the hazard ratio of mortality by Cox regression model were calculated accordingly to the AKIN criteria.
Results: The mean age of the included patients was 56.94 ± 9.49; 29 (63%) were male. Mean MELD score was 19.46 ± 6.16; 78.3% were Child-Pugh C. AKI occurred in 43.5% of patients (8.7, 17.4 and 17.4% respectively for AKIN criteria 1, 2 and 3). Inpatient mortality for AKIN 1, 2 and 3 was 50, 37.5 and 62.5 vs. 3.8% for patients without renal injury (p = 0.002, 0.001 and < 0.001 respectively). Patients with AKIN grades 1, 2 or 3 had no significant differences regarding MELD score (p = 0.893). The hazard ratio and 95% confidence interval of mortality for patients with AKI (AKIN grades 1, 2 and 3 grouped) were 3.41 (1.58-7.36).
Conclusions: AKIN criteria are useful to predict mortality in patients with SBP.