Abstract
Background: Infection is common in acute-on-chronic liver failure (ACLF), which may worsen the clinical condition and prognosis. However, the characteristics of infection and its influence on prognosis in hepatitis B virus related ACLF (HBV-ACLF) as defined by the European Association for the Study of the Liver (EASL) have not been clarified. We aimed to investigate the characteristics of infection and its influence on mortality in HBV-ACLF defined by EASL in China.Methods: We performed a retrospective cohort study with HBV-ACLF patients defined by EASL in a single center from January 2015 to December 2017. Patients were divided into an infection group and a non-infection group. The incidence, sites, strains of infection, and risk factors for mortality were evaluated. Results: A total of 289 patients were included, of which 185 (64.0%) were diagnosed with an infection. The most common was pneumonia (55.7%), followed by spontaneous bacterial peritonitis (47.6%) and others. The gram-negative bacteria were the most frequent (58.3%). Patients with one, two, and three or more infection sites had a gradually increasing incidence of sepsis (P<0.01), sepsis shock (P<0.001), and ACLF-3 (P<0.05). One, two, and three or more strains were isolated in 86, 16, and 18 patients, who showed a growing incidence of sepsis (P<0.01) and sepsis shock (P<0.001). Infection was identified as an independent risk factor for 28-day mortality in HBV-ACLF patients. Infected patients showed a significantly higher 28-day mortality than those without (P<0.01), especially in patients with ACLF-3. Pneumonia and sepsis were identified as independent predictors of 28-day mortality for infected patients.Conclusions: Infection is associated with severe clinical course and high mortality in HBV-ACLF defined by EASL. The increased incidence of sepsis and sepsis shock was associated with an increased number of infection sites and isolated strains. Pneumonia and sepsis were independent predictors affecting mortality in HBV-ACLF patients with infection.