DLL1 and inflammatory response: Crucially, the levels of DLL1 exhibited only marginal correlations with hepatic function parameters, indicating minimal confounding from liver inflammation, but failed to independently predict mortality in patients with ACLF and BI.<h4>Conclusion</h4>Serum DLL1 represents a robust and clinically deployable diagnostic biomarker for BI in patients with ACLF, and its performance is minimally affected by underlying hepatic dysfunction.