Spectrum of bacterial infections and predictors of mortality in adult cirrhotic patients

Background. Bacterial infections are more frequent in patients with decompensated cirrhosis than those with compensated liver disease and account for significant morbidity and mortality in them. Once an infection develops, it induces excessive production of pro-inflammatory cytokines leading to organ failure and death. Aims. This study aims to identify the clinical characteristics and outcome of bacterial infections affecting various organ systems in patients with liver cirrhosis and to determine factors associated with mortality. Methods. A cross sectional study was performed on subjects with cirrhosis having microbiologically proven bacterial infection involving various organ systems, admitted to a tertiary care hospital in southern India. Demographic, clinical data, laboratory parameters and outcome details were noted. Univariate associations and subsequent multivariate logistic regression analysis was performed to determine factors associated with mortality. Results. The study included 158 patients. Chronic alcohol intake was the most common etiology of cirrhosis (66.4%). Community acquired infections occurred more frequently than hospital acquired infections (85.5% vs 14.5%). The common site of isolation of etiological agent was ascitic fluid (38.3%) followed by blood (24.3%), respiratory tract (15.5%) and urinary tract (14.5%). Gram negative bacterial infections were more common (74.3%), Escherichia coli being the most frequent pathogen (38.5%). Mortality was noted in 38 (24%) patients. The factors associated with mortality were the type of infection, Child Pugh category, acute kidney injury, hepatic encephalopathy, urinary tract infection, and creatinine and bilirubin levels. Multivariate logistic regression analysis revealed that type of infection (OR: 0.33, 95% CI: 0.11-1.01), ascitic fluid infection (OR: 2.81, 95% CI: 1.11-7.12), hepatic encephalopathy (OR: 0.17, 95% CI: 0.070-0.422) and acute kidney injury (OR: 0.19, 95% CI: 0.077-0.502) were significantly associated with in-hospital mortality. Conclusion. This study indicates that the type of infection, hepatic encephalopathy, ascitic fluid infection and acute kidney injury are associated with mortality in cirrhotic patients. Early effective treatment and prevention of these complications may help modify the outcome.