Abstract: Objective The purpose of this study was to investigate the diagnostic efficacy of serum C-reactive protein (CRP) and soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) levels for secondary infections in patients with hepatitis B virus-associated acute-on-chronic liver failure (HBV-ACLF). Methods 96 consecutive patients with HBV-ACLF were encountered in our hospital between February 2020 and February 2023. Serum CRP and sTREM-1 levels were measured by ELISA. The multivariate Logistic regression analysis was conducted to identify the influencing factors for secondary infections in patients with HBV-ACLF. The diagnostic performance of above parameters was evaluated by using the receiver operating characteristic (ROC) curve. Results 67 (69.8%) patients with HBV-ACLF in our series developed secondary infections, and the spontaneous bacterial peritonitis, pulmonary infection, urinary tract infection, biliary tract infection, intestinal infection, and skin and soft tissue infection accounted for 40.3%, 31.3%, 11.9%, 4.5%, 4.5%, and 7.5%, respectively; the model of end-stage liver disease score and chronic liver failure sequential organ failure assessment score in patients with infection were (15.7±3.0) and (8.5±1.1), both significantly greater than [(12.40±3.00) and (6.1±1.0), P<0.05] in patients without infection; serum CRP and sTREM-1 levels in patients with infection were (52.2±4.6)mg/L and (29.9±5.8)pg/mL, both much higher than [(10.1±3.3)mg/L and (13.3±4.1)pg/mL, P<0.05] in those without; the Logistic regression analysis showed that the international normalization ratio, serum CRP, sTREM-1 and procalcitonin levels were all the independent risk factors for secondary infection (P<0.05); the ROC analysis demonstrated that the AUC was 0.906, with the sensitivity of 98.5% and the specificity of 82.8%, when serum CRP and sTREM-1 level combination was applied to predict the existence of infection, much superior to any parameter alone (P<0.05). Conclusion The surveillance of serum CRP and sTREM-1 level could help diagnose the secondary infections in patients with HBV-ACLF, which needs further clinical investigation.

Key words: Acute-on-chronic liver failure, C-reactive protein, Soluble triggering receptor expressed on myeloid cells-1, Secondary infection, Diagnosis