Ciampolini M, Bini S, Orsi A
Department of Pediatrics, University of Florence, Italy.
Physiol Behav. 1996 Dec;60(6):1551-6. doi: 10.1016/s0031-9384(96)00312-5.
A pathogenic role for high numbers of bacteria in the small intestine had been suggested previously by bacterial counts on luminal aspirates, but these investigations were flawed by the sampling device "contamination" in the mouth and the changing nature of fluent intestinal content. A procedure was developed to sterilize the Watson biopsy capsule with HCl in the upper portion of the duodenum. Bacteria were counted in the mucosal homogenate of the first (diagnostic) duodenojejunal biopsy in 80 untreated celiac children, and in 46 children with irritable bowel syndrome (IBS) in a four-cell, controlled, randomized investigation. Persistence of bacteria on the mucosa for 20 h after the last meal was investigated in 62 subjects, and for 26 h after the last meal in 64 subjects. Bacteria, mainly streptococci and staphylococci, persisted at a concentration of 10(6) per gram of mucosa 20 h after the last meal. The number of bacteria per gram of mucosa was 24 times higher in all 62 children of the 20-h fast groups than in all 64 children of the 26-h fast groups (p < 0.001). The bacteria count in celiac children was 39 times higher in the 20-h fast group than in the 26-h one. This difference was significantly higher than the 11 times difference that was found on the normal mucosa between the 20- and 26-h fast IBS groups (p < 0.001), which was still significant. The number of bacteria on duodenojejunal mucosa depends on nutrient absorption and persists longer than the intermeal interval in these subjects.
先前通过管腔吸出物中的细菌计数提示小肠中大量细菌具有致病作用,但这些研究存在口腔中采样装置“污染”以及肠道内容物性质不断变化的缺陷。开发了一种用盐酸在十二指肠上部对沃森活检胶囊进行消毒的程序。在一项四组对照随机研究中,对80名未经治疗的乳糜泻儿童以及46名肠易激综合征(IBS)儿童的首次(诊断性)十二指肠空肠活检的黏膜匀浆中的细菌进行了计数。在62名受试者中研究了最后一餐20小时后黏膜上细菌的持续存在情况,在64名受试者中研究了最后一餐26小时后细菌的持续存在情况。最后一餐20小时后,主要为链球菌和葡萄球菌的细菌以每克黏膜10⁶的浓度持续存在。在20小时禁食组的所有62名儿童中,每克黏膜的细菌数量比26小时禁食组的所有64名儿童高24倍(p<0.001)。乳糜泻儿童20小时禁食组的细菌计数比26小时禁食组高39倍。这种差异明显高于20小时和26小时禁食的IBS组正常黏膜之间11倍的差异(p<0.001),该差异仍然显著。十二指肠空肠黏膜上的细菌数量取决于营养吸收,并且在这些受试者中持续存在的时间比餐间间隔更长。