Bamba Shigeki, Imai Takayuki, Sasaki Masaya, Ohno Masashi, Yoshida Shinya, Nishida Atsushi, Takahashi Kenichiro, Inatomi Osamu, Andoh Akira
Division of Digestive Endoscopy, Shiga University of Medical Science, Otsu, Japan.
Division of Clinical Nutrition, Shiga University of Medical Science, Otsu, Japan.
J Gastroenterol Hepatol. 2023 Jan;38(1):61-69. doi: 10.1111/jgh.16013. Epub 2022 Oct 19.
Small intestinal bacterial overgrowth (SIBO) is diagnosed by using quantitative culture of duodenal aspirates and/or a hydrogen breath test. However, few studies have analyzed bacterial microbiota in Japanese patients with SIBO.
Twenty-four patients with any abdominal symptoms and suspected SIBO were enrolled. Quantitative culture of duodenal aspirates and a glucose hydrogen breath test were performed on the same day. SIBO was diagnosed based on a bacterial count ≥ 10 CFU/mL or a rise in the hydrogen breath level of ≥ 20 ppm. The composition of the duodenal microbiota was analyzed by 16S rRNA gene sequencing.
Small intestinal bacterial overgrowth was diagnosed in 17 of the 24 patients (71%). The positive rates for the hydrogen breath test and quantitative culture of duodenal aspirates were 50% and 62%, respectively. Patients with SIBO showed significantly reduced α-diversity compared with non-SIBO patients, and analysis of β-diversity revealed significantly different distributions between SIBO and non-SIBO patients. In addition, the intestinal microbiome in SIBO patients was characterized by increased relative abundance of Streptococcus and decreased relative abundance of Bacteroides compared with non-SIBO patients.
Duodenal dysbiosis was identified in patients with SIBO and may play a role in the pathophysiology of SIBO.
小肠细菌过度生长（SIBO）通过十二指肠抽吸物的定量培养和/或氢呼气试验来诊断。然而，很少有研究分析日本SIBO患者的细菌微生物群。
纳入24例有任何腹部症状且疑似SIBO的患者。在同一天进行十二指肠抽吸物的定量培养和葡萄糖氢呼气试验。根据细菌计数≥10⁵ CFU/mL或氢呼气水平升高≥20 ppm诊断SIBO。通过16S rRNA基因测序分析十二指肠微生物群的组成。
24例患者中有17例（71%）被诊断为小肠细菌过度生长。氢呼气试验和十二指肠抽吸物定量培养的阳性率分别为50%和62%。与非SIBO患者相比，SIBO患者的α多样性显著降低，β多样性分析显示SIBO患者和非SIBO患者之间的分布存在显著差异。此外，与非SIBO患者相比，SIBO患者肠道微生物群的特征是链球菌相对丰度增加，拟杆菌相对丰度降低。
在SIBO患者中发现十二指肠生态失调，其可能在SIBO的病理生理学中起作用。
