[en] BACKGROUND AND STUDY AIMS: The small intestine is a potential origin of bleeding in patients with unexplained gastrointestinal tract hemorrhage or iron-deficiency anemia. Most reports on the investigation of these patients describe the use of upper tract enteroscopy. The diagnostic yield of combined upper and lower enteroscopy has not been widely assessed and remains to be clarified. The aim of this study was to assess the benefit of lower gastrointestinal tract enteroscopy in occult digestive bleeding. PATIENTS AND METHODS: Between 1 December 1995 and 15 January 1998, 54 patients with gastrointestinal bleeding of unknown origin were prospectively studied using upper and lower video push enteroscopy (44 for chronic iron-deficiency anemia and 10 for unexplained gastrointestinal tract hemorrhage with no potential site having been identified by other investigations). Examinations were done using a Olympus video enteroscope (SIF-100) under general anesthesia in a one-day clinic. An upper tract examination was done first, directly followed by the lower tract investigation. RESULTS: The upper tract enteroscopy was successful in 53 patients (98%) and retrograde ileoscopy in 21 patients (39%). In 18 (38%) cases the technical failure resulted from the impossibility of intubating the ileocecal valve. A potential source of upper gastrointestinal bleeding was detected in 35% of patients with chronic iron-deficiency anemia and in 20% of those with unexplained gastrointestinal tract hemorrhage. The most common lesion in the small bowel was angiodysplasia (25%). The lower tract video push enteroscopy disclosed 11 lesions in patients with chronic anemia. However the lesions, including two ileocecal valve cancers, were mainly located in the colon and had been missed by previous colonoscopy. No case of ileal lesion was detected in this group of patients. In patients with unexplained gastrointestinal tract hemorrhage, three lesions were detected but only one of these was in the ileum. Associated colonic and jejunal lesions were observed in three patients (5.5%). Overall, the diagnostic yield of lower video push enteroscopy was less than 2%. CONCLUSION: This prospective study has shown that using an enteroscope as a colonoscope in the management of patients with gastrointestinal bleeding of unknown origin is of little help. It might actually be more appropriate to perform a second colonoscopy. This however remains controversial and a prospective study is needed to answer that question.