Abstract: Objective The aim of this prospective study is to verify four bleeding criteria in patients with acute-on-chronic liver failure（ACLF）. Method We prospectively enrolled 56 patients with non-ACLF,26 with Asian Pacific Association for the Study of the Liver （APASL）-ACLF and 12 with European Association for the Study of the Liver（EASL）-ACLF）,and evaluated their bleeding events by using four bleeding criteria,e.g. Bleeding Academic Research Consortium（BARC）,Thrombolysis in myocardial infarction（TIMI）,Global Use of Strategies To Open Coronary Arteries（GUSTO） and International Society on Thrombosis and Haemostasis （ISTH）. Result Out of the 94 patients,bleeding events occurred in 57.6%,and lethal bleeding events was 1.1%;the bleeding incidence in patients with non-ACLF was 41.1%,significant lower than 76.9% in patients with APASL-ACLF or 100.0% in patients with EASL-ACLF（both P<0.05）;patients with bleeding had higher 28 day and 90 day mortality rate than those without bleeding （13.0% vs. 0.0% and 24.5% vs. 0.0%,respectively,P<0.05）;the area under curve of receiver operating characteristic（AUC） in predicting 28 day mortality by ISTH was 0.95 （95%CI:0.861-1.000）,significant wider than by BARC[0.880（95%CI:0.747-1.000,P<0.05）] or by TIMI [0.801（95%CI:0.653-0.948,P<0.05）]. Conclusion Bleeding events are common in patients with ACLF and the incidence increases in accordance with the severity of the diseases,though the fatal bleeding events are rare. ISTH bleeding criteria is recommended for assessment of hemorrhagic events in patients with ACLF.

Key words: Acute-on-chronic liver failure, Bleeding criteria, Short-term prognosis