摘要艰难梭菌感染（CDI）指由艰难梭菌引起的肠道感染，主要临床症状为发热、腹痛、水样便、腹泻。轻者表现为腹泻，严重者可发生伪膜性肠炎，且常伴有中毒性巨结肠、肠穿孔、感染性休克等并发症；是常见的医院内感染类型，是住院患者特别是老年患者出现并发症和死亡的重要原因。本部指南的撰写目的是对CDI患者的诊断、治疗及预防提供指导。指南内容包括CDI的诊断、治疗及预防三个方面，共20个临床问题。本指南的制定主要由指南专家组和指南工作组两个交叉合作的专家团队完成。其中指南专家组由与CDI诊断、治疗和感染控制相关的18个专业的37名临床专家组成。本部指南采用国际公认的GRADE标准和流程制定，GRADE包括证据级别和推荐强度。GRADE系统将证据级别分为高、中、低和极低4个等级。制定推荐意见时，考虑了医学干预的利弊平衡、证据质量、价值观念与偏好，以及成本与资源耗费等因素，并将推荐意见分为强推荐和弱推荐（有条件推荐）两种。本部指南的应用对象为中国医师和患者。

abstractsClostridium difficile infection(CDI) is an intestinal infection caused by Clostridium difficile,characterized by clinical symptoms such as fever,abdominal pain,watery diarrhea,and loose stools. Mild cases present with diarrhea,while severe cases can progress to pseudomembranous colitis,often accompany by complications such as toxic megacolon,intestinal perforation,and septic shock. CDI is a significant cause of complications and mortality,especially among elderly patients,and is one of the most common hospital-acquired infections. The purpose of this guideline is to provide guidance on the diagnosis,treatment,and prevention of CDI,covering a total of 20 clinical questions across three domains: diagnosis,treatment,and prevention. The guideline was developed by a collaborative effort of a guideline expert group and a guideline working group. The guideline expert group consists of 37 clinical experts in 18 specialties related to the diagnosis and treatment of CDI and healthcare associated infection control. This guideline was developed using the internationally recognized GRADE method. It includes evidence evaluation and recommendation grading. It categorizes the quality of evidence into four levels: high,medium,low and very low. When formulating recommendations,it considers factors such as the balance of benefits and harms of intervention,quality of evidence,values and preferences,as well as cost and resource consumption. The recommendations are classified into strong and weak recommendations(conditional recommendations). The target audience of this guideline includes Chinese doctors and patients.