BACKGROUND Postoperative complications after colorectal cancer surgery have been linked to the gut microbiome. However, the impact of mechanical bowel preparation using oral preparation agents or rectal enema on postoperative infections remains poorly understood. This study aimed to compare the impact of oral preparation and rectal enema on the gut microbiome and postoperative complications. METHODS This open-label pilot RCT was conducted at the National Cancer Institute, Vilnius, Lithuania. Patients with left-side colorectal cancer scheduled for elective resection with primary anastomosis were randomized 1 : 1 to preoperative mechanical bowel preparation with either oral preparation or rectal enema. Stool samples were collected before surgery, and on postoperative day 6 and 30 for 16S rRNA gene sequencing analysis. The primary outcome was difference in β-diversity between groups on postoperative day 6. RESULTS Forty participants were randomized to oral preparation (20) or rectal enema (20). The two groups had similar changes in microbiome composition, and there was no difference in β-diversity on postoperative day 6. Postoperative infections occurred in 12 patients (32%), without differences between the study groups. Patients with infections had an increased abundance of bacteria from the Actinomycetaceae family, Actinomyces genus, Sutterella uncultured species, and Enterococcus faecalis species. CONCLUSION Mechanical bowel preparation with oral preparation or rectal enema resulted in similar dysbiosis. Patients who experienced postoperative infections exhibited distinct gut microbiome compositions on postoperative day 6, characterized by an increased abundance of bacteria from the Actinomycetaceae family, Actinomyces genus, Sutterella uncultured species, and Enterococcus faecalis species. REGISTRATION NUMBER NCT04013841 (http://www.clinicaltrials.gov).

中文翻译：

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机械肠道准备对接受左侧结直肠癌手术的患者肠道微生物群的影响：随机临床试验。


背景结直肠癌手术后的术后并发症与肠道微生物组有关。然而，使用口服制剂或直肠灌肠进行机械肠道准备对术后感染的影响仍知之甚少。本研究旨在比较口服制剂和直肠灌肠对肠道微生物组和术后并发症的影响。方法 这项开放标签试点随机对照试验是在立陶宛维尔纽斯国家癌症研究所进行的。计划进行选择性切除和一期吻合术的左侧结直肠癌患者以 1:1 的比例随机接受术前机械肠道准备（口服制剂或直肠灌肠）。术前、术后第6天和第30天收集粪便样本进行16S rRNA基因测序分析。主要结果是术后第 6 天各组间 β 多样性的差异。 结果 40 名参与者被随机分配接受口服制剂 (20) 或直肠灌肠 (20)。两组微生物组组成的变化相似，术后第 6 天的 β 多样性没有差异。12 名患者（32%）发生术后感染，研究组之间没有差异。感染患者的放线菌科、放线菌属、未培养的萨特氏菌属和粪肠球菌属细菌丰度增加。结论 采用口服制剂或直肠灌肠进行机械肠道准备会导致类似的菌群失调。 经历术后感染的患者在术后第 6 天表现出不同的肠道微生物组组成，其特征是来自放线菌科、放线菌属、Sutterella 未培养物种和粪肠球菌物种的细菌丰度增加。注册号 NCT04013841 (http://www.clinicaltrials.gov)。