This study aimed to investigate the impact of IL-35 on the prognosis of patients with HBV-ACLF. We recruited 69 patients with HBV-ACLF, 20 patients with chronic hepatitis B (CHB), 17 patients with liver cirrhosis (LC), and 20 healthy controls (HCs) from a regional infectious disease treatment center in China. Plasma levels of IL-35 at baseline were detected using ELISA. Plasma IL-35 levels in the HBV-ACLF group were the highest among all four groups. Furthermore, survivors exhibited significantly higher IL-35 levels than non-survivors (p p p p p = 0.001), and lactate (r =−0.38, p =0.001). The combination of plasma IL-35 and MELD score had the highest mortality prediction efficiency, with an area under the curve (AUC) of 0.895 (95% CI: 0.812–0.978, p p < 0.001). Our results demonstrated that IL-35 could be an effective predictive marker for the prognosis of HBV-ACLF and improve the predictive performance when combined with the MELD score.
