下消化道出血是指Treitz韧带以下的肠道出血。包括小肠、结肠、直肠和肛管等部位。约占消化道出血的15%,较上消化道出血相对少见。病因复杂,出血部位难以判断。近十年来随着诊断技术及治疗水平的提高,下消化道出血的病死率和手术机会均明显下降,但仍有少数患者尤其是除外了大肠出血的患者,其出血的原因不能明确,并可能发生误诊。 Lower gastrointestinal bleeding refers to intestinal bleeding below the Treitz ligament. Including the small intestine, colon, rectum and anal canal and other parts. About 15% of gastrointestinal bleeding, upper gastrointestinal bleeding is relatively rare. Complex etiology, bleeding site difficult to judge. In the past decade, with the improvement of diagnostic techniques and treatment, mortality and surgical chance of lower gastrointestinal bleeding have dropped significantly. However, there are still a few patients, especially patients with large intestinal bleeding, whose causes of bleeding are not clear and possibly Misdiagnosis occurred.