Abstract: Objective The purpose of this study was to investigate the prevalence of bacterial infection in patients with hepatitis B viral infection-related acute-on-chronic liver failure (HBV-ACLF). Methods The clinical materials of 214 patients with HBV-ACLF between January 2015 and February 2022 were retrieved from His system in our hospital, and various infections were defined according to related criteria. The multivariate Logistic regression analysis was applied to reveal the impacting factors for infection. Results Out of the 214 patients with HBV-ACLF, the bacteria infection was found in 145 cases(67.7%), involving one organ in 113 cases, two in 28 cases and three in 4 cases, including spontaneous bacterial peritonitis (SBP) in 127 cases (85.2%), pulmonary infection in 41 cases (27.5%), acute cholecystitis in 25 cases(16.8%), urinary tract infection in 4 cases (2.7%) and perianal infection in 2 cases (1.3%); there were significant differences as respect to ages, systemic inflammatory response syndrome (SIRS) score, peripheral white blood cell counts, platelet counts, C-reactive protein, procalcitonin, prothrombin time activity (PTA), serum bilirubin, albumin, the incidence of hepatic encephalopathy (HE) and ascites between patients with and without bacterial infections(P<0.05); the multivariate Logistic analysis showed that the age, SIRS scores, WBC counts, PCT and ascites were the independent risk factors, while the PTA and serum albumin levels were the protective ones for bacterial infection in patients with HBV-ACLF(P<0.05); we set the SIRS score as the basic parameter, and its combination with age in predicting bacterial infection had the sensitivity (Se) and specificity (Sp) of 75.9% and 55.1%, with WBC counts of 77.2% and 62.3%, with PTA of 79.3% and 59.4%, with PCT of 89.7% and 46.4%, with ALB of 80.7% and 63.8%, and with ascites of 67.6% and 72.5%, suggesting a good Se with relatively low Sp. Conclusion The patients with HBV-ACLF are prone to bacterial infection, and some factors, such as elderly persons, hyperbilirubinemia and severe coagulation dysfunction, might trigger the infection, which should be appropriately dealt with as early as possible in clinical practice.

Key words: Acute-on-chronic liver failure, Bacterial infection, Systemic inflammatory response syndrome, Spontaneous peritonitis, Multivariate Logistic analysis