Background and aims:Acute appendicitis(AA)is among the most common causes of acute abdominal pain.Diagnosis of AA is still challenging and some controversies on its management are still present among different settings and practice patterns worldwide.

In July 2015,the World Society of Emergency Surgery(WSES)organized in Jerusalem the first consensus conference on the diagnosis and treatment of AA in adult patients with the intention of producing evidence-based guidelines.An updated consensus conference took place in Nijemegen in June 2019 and the guidelines have now been updated in order to provide evidence-based statements and recommendations in keeping with varying clinical practice:use of clinical scores and imaging in diagnosing AA,indications and timing for surgery,use of nonoperative management and antibiotics,laparoscopy and surgical techniques,intra-operative scoring,and perioperative antibiotic therapy.

Methods:This executive manuscript summarizes the WSES guidelines for the diagnosis and treatment of AA.Literature search has been updated up to 2019 and statements and recommendations have been developed according to the GRADE methodology.The statements were voted,eventually modified,and finally approved by the participants to the consensus conference and by the board of co-authors,using a Delphi methodology for voting whenever there was controversy on a statement or a recommendation.Several tables highlighting the research topics and questions,search syntaxes,and the statements and the WSES evidence-based recommendations are provided.Finally,two different practical clinical algorithms are provided in the form of a flow chart for both adults and pediatric(<16 years old)patients.

Conclusions:The 2020 WSES guidelines on AA aim to provide updated evidence-based statements and recommendations on each of the following topics:(1)diagnosis,(2)non-operative management for uncomplicated AA,(3)timing of appendectomy and in-hospital delay,(4)surgical treatment,(5)intra-operative grading of AA,(6),management of perforated AA with phlegmon or abscess,and(7)peri-operative antibiotic therapy.

背景和目的：急性阑尾炎（AA）是急性腹痛的最常见原因之一。AA的诊断仍然具有挑战性，全球不同环境和实践模式对其管理仍存在一些争议。

2015年7月，世界急诊外科学会（WSES）在耶路撒冷组织了关于成人患者AA诊断和治疗的第一次共识会议，目的是制定循证指南。2019年6月在Nijemegen召开了更新共识会议，指南现已更新，以便提供符合不同临床实践的循证声明和建议：使用临床评分和成像诊断AA、手术适应症和时机、使用非手术治疗和抗生素、腹腔镜和手术技术、术中评分和围手术期抗生素治疗。

方法：本执行手稿总结了WSES AA-诊断和治疗指南。文献检索已更新至2019年，并根据GRADE方法制定了声明和建议。声明经过表决，最终进行了修改，并最终获得了共识会议与会者和共同作者委员会的批准，当对声明或建议存在争议时，使用Delphi方法进行表决。提供了几个表格，突出显示研究课题和问题、检索语法以及声明和WSES循证建议。最后，以流程图的形式提供了两种不同的实用临床算法，用于成人和儿童（<16岁）患者。

结论：2020年WSES AA指南旨在提供关于以下每个主题的最新循证声明和建议：（1）诊断，（2）非复杂性AA的非手术治疗，（3）阑尾切除术的时机和住院延迟，（4）手术治疗，（5）AA的术中分级，（6）伴蜂窝织炎或脓肿的穿孔AA的治疗，以及（7）围手术期抗生素治疗。