Area Editoriale
Lower-GI (LGI) bleeding is defined as bleeding distal to the ligament of Treitz. The annual incidence of LGI bleeding is estimated to be 20 to 27 cases per 100,000 adult population at risk. When patients hospitalized for GI bleeding are identified, LGI sources account for a quarter to a third of all bleeding events. Lower-GI bleeding is more common in men than in women, and the incidence rate increases with age, with a greater than 200-fold increase from the 3rd to the 9th decades of life. The mortality rate for LGI bleeding is reported at 3.6% and, similar to upper-GI (UGI) bleeding, mortality is markedly higher in patients who begin bleeding after hospitalization. In contrast to UGI bleeding, patients with LGI bleeding are less likely to present with shock and to have lower transfusion requirements. Similar to UGI bleeding, spontaneous cessation of bleeding occurs in approximately 80% of cases.In most patients whose bleeding ceases spontaneously, an elective colonoscopy after routine preparation is indicated. Patients with continued bleeding require urgent diagnosis. Unless the bleeding is massive, rapid intestinal lavage allows adequate preparation for urgent colonoscopy. Although the historical view was that colonoscopy in patients with severe hematochezia is impractical because of inadequate visualization, colonoscopy is feasible and useful after prior rapid cleansing. Urgent colonoscopy makes a final diagnosis of colonic lesions in 74% to 90% of patients. In one series that included prior upper endoscopy, UGI lesions were diagnosed in 11%, presumed small-bowel lesions in 9%, and no site in 6% of 80 patients with ongoing hematochezia. This diagnostic accuracy is better than that of arteriography. Despite these data, controversy continues about the value of urgent colonoscopy and endoscopic treatment of LGI bleeding stigmata. The purpose of this review is to highlight the recent publications on this topic and to point out the need for further prospective studies.