Bixquert Jiménez M
Department of Medicine, School of Medicine (Gastroenterology Teaching Unit), University of Valencia, Spain.
Rev Esp Enferm Dig. 2009 Aug;101(8):553-64. doi: 10.4321/s1130-01082009000800006.
Irritable bowel syndrome (IBS) is the most common functional digestive disorder, and may affect 11-20% of the adult population in industrialized countries. In accordance with Rome III criteria (2006) IBS involves abdominal pain and bowel habit disturbance, which are not explained by structural or biochemical abnormalities. Several hypotheses attempt to account for the pathophysiology of IBS, but the etiology still remains uncertain or obscure, perhaps multifactorial. Abnormalities in colonic microflora have recently been suggested in such patients, as has abnormal small-intestine bacterial overgrowth (SIBO), or in particular a significant reduction in the amount of intraluminal Bifidobacteria or Lactobacilli, with consequences like the production of colonic gas, and motility or sensitivity disturbances of the intestinal tract. The disorder is difficult to treat, and the wide spectrum of non-drug and drug treatments shows our ignorance about the cause of the condition. Newer drugs, both pro- and anti-serotonin, have failed to show long-term efficacy or have been withdrawn due to concerns about harmful effects. Recent research has provided increasing support for the idea that disturbances of intestinal microbiota occur in patients with IBS, and that such abnormalities may contribute to IBS symptoms. Studies in Scandinavian countries in the last ten years emphasize the role of probiotics in the modulation of intestinal microbiota, and as a consequence in the regulation of the motility and hypersensitivity of the digestive tract. Although results between studies are difficult to compare because of differences in study design, probiotic dose, strain, and duration of therapy, some studies show symptom improvement. Lactobacilli are found among the normal bacterial flora of the gastrointestinal tract, and Lactobacillus plantarum (Lp) is one of the species frequently isolated from the human mucosa, which is capable of surviving the low pH of the stomach and duodenum, resisting the effect of bile acids in the upper small intestine when ingested, and temporarily colonizing the gastrointestinal tract by binding to the intestinal and colonic mucosa. Concurrent with colonization by Lp there is a decrease in bacterial groups with gas-producing ability, such as Veillonella spp. and Clostridia spp. Evidence has now accumulated to suggest the efficacy of certain probiotics like Lp299v, which may be capable of bringing about a significant reduction in pain, abdominal distension and flatulence, while increasing health-related quality of life in IBS.
肠易激综合征（IBS）是最常见的功能性消化紊乱疾病，在工业化国家可能影响11% - 20%的成年人口。根据罗马III标准（2006年），IBS包括腹痛和排便习惯紊乱，且这些症状无法用结构或生化异常来解释。有几种假说试图解释IBS的病理生理学，但病因仍不明确或模糊，可能是多因素的。最近有人提出，此类患者存在结肠微生物群异常，以及小肠细菌过度生长（SIBO）异常，特别是管腔内双歧杆菌或乳酸杆菌数量显著减少，从而导致结肠气体产生、肠道动力或敏感性紊乱等后果。这种疾病难以治疗，广泛的非药物和药物治疗方法表明我们对其病因并不了解。新型药物，无论是促5-羟色胺类还是抗5-羟色胺类，都未能显示出长期疗效，或因担心有害影响而被撤回。最近的研究越来越支持这样一种观点，即IBS患者存在肠道微生物群紊乱，且这种异常可能导致IBS症状。过去十年在斯堪的纳维亚国家进行的研究强调了益生菌在调节肠道微生物群方面的作用，进而在调节消化道动力和超敏反应方面的作用。尽管由于研究设计、益生菌剂量、菌株和治疗持续时间的差异，不同研究结果难以比较，但一些研究显示症状有所改善。乳酸杆菌存在于胃肠道的正常细菌菌群中，植物乳杆菌（Lp）是经常从人体黏膜分离出的菌种之一，它能够在胃和十二指肠的低pH环境中存活，摄入后能抵抗上小肠中胆汁酸的作用，并通过与肠道和结肠黏膜结合而暂时在胃肠道定植。随着Lp的定植，具有产气能力的细菌群，如韦荣氏菌属和梭菌属，数量会减少。现在已有证据表明某些益生菌，如Lp299v，可能有效，它能够显著减轻疼痛、腹胀和肠胃气胀，同时提高IBS患者与健康相关的生活质量。
