Bounds Brenna Casey, Friedman Lawrence S
Department of Medicine, Harvard Medical School, Gastrointestinal Unit, Massachusetts General Hospital, 55 Fruit Street, Blake 453C, Boston, MA 02114, USA.
Gastroenterol Clin North Am. 2003 Dec;32(4):1107-25. doi: 10.1016/s0889-8553(03)00086-4.
Lower gastrointestinal bleeding is defined as blood loss that originates from a source distal to the ligament of Treitz and results in hemodynamic instability or symptomatic anemia. Although approximately 10% to 15% of patients presenting with acute severe hematochezia have an upper gastrointestinal source of bleeding identified on upper endoscopy, the most common causes of lower gastrointestinal bleeding are diverticulosis, hemorrhoids, ischemic colitis, and angiodysplasia. As with upper gastrointestinal bleeding, lower gastrointestinal bleeding ceases spontaneously in most cases.
下消化道出血定义为源自屈氏韧带远端的失血，可导致血流动力学不稳定或症状性贫血。尽管约10%至15%表现为急性严重便血的患者在上消化道内镜检查中被发现有上消化道出血源，但下消化道出血最常见的原因是憩室病、痔疮、缺血性结肠炎和血管发育异常。与上消化道出血一样，下消化道出血在大多数情况下会自行停止。
