Luminal bacteria and small-intestinal permeability
Luminal bacteria and small-intestinal permeability
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DOI：
10.3109/00365529709025099
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发表时间：
1997-06-01
影响因子：
1.9
通讯作者：
Thomas, MC
中科院分区：
文献类型：
--
作者：
Riordan, SM;McIver, CJ;Thomas, MC
背景：肠腔细菌对小肠通透性的影响尚未得到充分评估。本研究解决了这个问题。方法：通过小肠抽吸物培养，对 34 名受试者（平均年龄 64 岁；范围 22-95 岁）进行了可能的小肠细菌过度生长 (SIBO) 调查。对所有受试者进行乳果糖/甘露醇小肠渗透性测试、评估小肠组织学并测量血清维生素 B-12 浓度。还对 34 名无症状志愿者组成的对照组进行了渗透性评估。结果：即使没有绒毛萎缩，患有结肠型菌群的 SIBO 受试者的尿乳果糖/甘露醇比率也显着增加 (P < 0.0005)。在校正受试者间肾功能差异后，由于尿乳果糖浓度显着增加（P < 0.0005）而不是尿甘露醇水平降低，该组尿乳果糖/甘露醇比率增加。本组CD8表型上皮内淋巴细胞计数显着增加（P = 0.003）。尽管上皮内淋巴细胞计数与小肠通透性总体之间存在显着相关性（P < 0.002），但在具有结肠型菌群的 SIBO 受试者中，这些计数在通透性值小于或等于或 > 0.028（无症状对照的正常上限）的受试者中没有显着差异。血清维生素 B-12 浓度在各组之间没有显着差异 (P > 0.5)。衰老并不独立影响小肠通透性（P > 0.5）。结论：患有结肠型细菌的 SIBO 受试者的小肠通透性增加。这种作用与衰老无关，也不是由维生素 B-12 缺乏介导的。尽管在这种疾病中 CD8 表型的上皮内淋巴细胞计数增加，但这些细胞也不太可能在此过程中发挥重要的致病作用。常规光学显微镜评估低估了这种疾病中小肠功能障碍的患病率。
Background: The influence of luminal bacteria on small-intestinal permeability has not been fully assessed. This study addressed this issue. Methods: Thirty-four subjects (mean age 64 years; range 22-95 years) were investigated for possible small-intestinal bacterial overgrowth (SIBO) with culture of a small-intestinal aspirate. A lactulose/mannitol small-intestinal permeability test was performed, small-intestinal histology assessed and serum vitamin B-12 concentrations measured in all subjects. Permeability was also assessed in a control group of 34 asymptomatic volunteers. Results: Urinary lactulose/mannitol ratios were significantly increased in subjects with SIBO with colonic-type flora (P < 0.0005), even in the absence of villous atrophy. Urinary lactulose/mannitol ratios were increased in this group due to significantly increased urinary lactulose concentrations (P < 0.0005) rather than reduced urinary mannitol levels, after correcting for inter-subject variations in renal function. Counts of intraepithelial lymphocytes of CD8 phenotype were significantly increased in this group (P = 0.003). Although a significant correlation was found between intraepithelial lymphocyte counts and small-intestinal permeability overall (P < 0.002), these counts were not significantly different in subjects with SIBO with colonic-type flora whose permeability values were less than or equal to or > 0.028, the upper limit of normal in asymptomatic controls. Serum vitamin B-12 concentrations did not differ significantly between groups (P > 0.5). Ageing did not independently influence small-intestinal permeability (P > 0.5). Conclusions: Small-intestinal permeability is increased in subjects with SIBO with colonic-type bacteria. This effect is independent of ageing and not mediated by vitamin B-12 deficiency. Although counts of intraepithelial lymphocytes of CD8 phenotype are increased in this disorder, it is also unlikely that these cells play an important causative role in this process. Routine light microscopic assessment underestimates the prevalence of small-intestinal functional disturbance in this disorder.