肠道正常菌群的菌种多达100种以上。这些正常茵群与宿主呈共生关系,不仅有助于食物消化、吸收和肠内容物解毒,同时还具有排除外来病原微生物的作用。使用抗菌药物,可引起下列多种结肠疾患,其发生大多与菌交替症有关。1.难辨梭状杆菌性肠炎:难辨梭状杆菌(C.difficile)为专性厌氧性革兰氏阳性杆菌,部分菌株能产生毒素。虽然在0～29.4% The normal intestinal flora of up to 100 kinds of bacteria. These normal Yin population and host symbiotic relationship, not only contribute to food digestion, absorption and intestinal contents detoxification, but also has the role of excluding foreign pathogenic microorganisms. The use of antibacterial drugs, can cause a variety of colon disorders, most of which occur with bacterial alternation. 1. Clostridium difficile enteritis: C. difficile is an obligate anaerobic Gram-positive bacterium, and some strains produce toxins. Although in 0 ~ 29.4%