摘要高通量宏基因测序、代谢组学等技术研究发现人体肠道内栖息种类超过1 500多种，生物量接近于10 14菌落形成单位，并给机体增加约60万个基因。微生物及其代谢产物在人体内起生物屏障、参与免疫系统成熟和免疫应答的调节，并对机体生理代谢起着重要作用。年龄、环境、饮食、疾病及用药等因素会引起肠道微生态失衡，同时肠道微生态变化与感染(尤其是耐药菌感染，二重感染)、肝病、消化道疾病、肿瘤、糖尿病、肥胖、自闭症、阿尔茨海默病、高血压的发生发展等密切有关，肠道微生态可为各类相关疾病甚至是肿瘤免疫治疗提供诊断工具和治疗策略。微生态调节剂对各种原因引起的肠道微生态失衡起较好的调节作用，随着人体微生态学研究的深入和发展，微生态调节剂的品种和应用也越来越广泛。近年来，微生态基础及临床应用研究发展迅速，微生态学研究技术及相关的概念颠覆了以往的医学认知。因此我们在第一版的基础上修订新版中国微生态调节剂临床应用专家共识，以供广大临床医师在选择和应用微生态调节剂时参考。

abstractsHigh-throughput metagenomics sequencing, metabolomics and other techniques have showed that there are more than 1, 500 species of microorganisms living in the human intestinal tract, and the biomass is close to 10 14 colony forming units, and about 600, 000 genes are added to the human body. Microorganisms and their metabolites act as biological barriers in human body, participate in the regulation of immune system maturation and immune response, and play an important role in physiological metabolism of the body. Factors such as age, environment, diet, disease and medication can cause intestinal microecological imbalance, at the same time there are closely relationship between the change of intestinal microecology and the occurrence and development of infection (especially drug-resistant bacteria infection, super infection), hepatic disease, gastrointestinal disease, tumor, diabetes, obesity, autism, Alzheimer’s disease and hypertension. Intestinal microecology can provide diagnostic tools and treatment strategies for various related diseases and even the tumor immunotherapy. Microecological preparations play a great role in regulating intestinal microecological imbalance caused by various causes. With the development of human microecology research, the varieties of microecological modulators are increasing and their applications are extending. In recent years, the basic and clinical application research of microecology have been rapidly developed, and the research techniques and related concepts of microecology have overturned some previous medical cognition. Therefore, based on the first edition, we have compiled the new edition of expert consensus on the clinical application of microecological modulators in China to provide a reference for clinicians in the selection and application of microecological modulators.