Abstract: Objective To investigate the risk factors of bacterial infection in patients with decompensated cirrhosis and the value of early diagnosis by inflammation index. Methods A retrospective analysis was performed on 278 patients with decompensated cirrhosis admitted to our hospital from January 2022 to December 2023. According to whether the patients were accompanied by bacterial infection, they were divided into an infected group (102 cases) and a non-infected group (176 cases). The clinical characteristics of infection were analyzed. Multiple logistic regression was used to analyze the risk factors of decompensated cirrhosis complicated with bacterial infection. The value of white blood cell count (WBC), neutrophil to lymphocyte count ratio (NLR), C-reactive protein (CRP) and procalcitonin (PCT) in early diagnosis of decompensated cirrhosis complicated with bacterial infection was calculated by receiver operating characteristic curve (ROC). Results Decompensated cirrhosis is prone to complications of respiratory tract infection and spontaneous peritonitis, and the pathogenic bacteria are mainly Escherichia coli (36.8%) and Klebsiella pneumoniae (22.8%). Multivariate analysis suggests that diabetes mellitus, upper gastrointestinal hemorrhage, and Child-Pugh grade C are the risk factors of bacterial infection in cirrhosis patients. The clinical reference value for the diagnosis of decompensated cirrhosis complicated with bacterial infection was calculated by ROC curve: the clinical reference value of WBC was 6.25×10⁹/L (AUC=0.787, P<0.05, 95%CI 0.720~0.855), and the clinical reference value of NLR was 3.17 (AUC=0.706, P<0.05, 95%CI 0.631~0.781), the clinical reference value of CRP was 15.19 mg/L (AUC=0.621, P<0.05, 95%CI 0.536~0.707), and the clinical reference value of procalcitonin was 0.335ng/mL (AUC=0.835, P<0.05, 95%CI 0.774~0.895), the sensitivity and specificity of the combined diagnosis were 90.6% and 64.3%, respectively. Conclusion Patients with decompensated cirrhosis are prone to complicated with respiratory tract infection and spontaneous peritonitis, mainly caused by Escherichia coli and Klebsiella pneumoniae. Patients with cirrhosis combined with diabetes, upper gastrointestinal hemorrhage and Child-Pugh grade C are prone to bacterial infection. During clinical diagnosis and treatment, the WBC count, NLR, C-reactive protein, procalcitonin and other inflammatory indicators should be dynamically monitored for patients with decompensated cirrhosis with the abovel risk factors, so as to early detect and promptly treat potential infection and improve prognosis.

Key words: Liver cirrhosis, Infection, Risk factors, Inflammatory index