Aim: Recently, new diagnostic criteria for acute-on-chronic liver failure (ACLF) were established in Japan. However, there is little evidence regarding the feasibility of classifying patients undergoing living-donor liver transplantation (LDLT). The aim was to re-evaluate the impact of these new diagnostic criteria on ACLF and the severity classification of patients undergoing LDLT. Methods: We collected data of 82 recipients who underwent LDLT for liver failure between 1997 and 2020 and reviewed it retrospectively. Results: Of the 82 patients with liver failure, 31 (37.8%) were diagnosed with ACLF; Grade 0 (n = 6), Grade 1 (n = 7), Grade 2 (n = 9), and Grade 3 (n = 9). There was no substantial difference in overall survival (OS) and the occurrence of postoperative complications between liver failure patients with and without ACLF. The OS after LDLT was significantly different among the four groups of ACLF patients (P =.036). Interestingly, ACLF Grade 3 patients had substantially lower OS compared to other ACLF groups even after LDLT (P =.006; 5-year OS rates, 33.3% vs. 85.9%). Conclusion: Proper use of the new diagnostic criteria for ACLF in Japan demonstrated that the presence and severity of ACLF, especially the presence of multiple organ failures, leads to morbidity and mortality even in an LDLT setting. Considering that the patients with ACLF Grade 3 do not have the favorable outcomes of LDLT, deceased-donor liver transplantation usage, or LDLT before reaching the severity of Grade 3 may be suitable for further research.
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