RESUMEN
BACKGROUND AND STUDY AIMS: Capsule endoscopy is considered the diagnostic procedure of choice in patients with obscure gastrointestinal bleeding (OGIB). Double-balloon endoscopy (DBE) offers both diagnostic and therapeutic potential, but is invasive, complex, and time-consuming. The aim was to evaluate diagnostic agreement between capsule endoscopy and DBE in patients with OGIB, and secondarily the diagnostic gain of DBE when capsule endoscopy detected only blood or clots in the small-bowel lumen. METHODS: Multicenter prospective study carried out at six institutions in Italy. RESULTS: 193 patients (119 men, mean age 61.6 +/- 16.2) first underwent capsule endoscopy and then DBE. The most frequent positive findings at capsule endoscopy were vascular lesions (74 patients, 38.3 %), blood or clot in the lumen (34, 17.6 %), and tumor mass (20, 10.4 %). The most frequent findings at DBE were vascular lesions (72 patients, 37.3 %), neoplasia (30, 15.5 %) and ulcers/inflammatory lesions (12, 6.2 %). Overall kappa coefficient was 0.46 (95 %CI 0.38 - 0.54), with maximum concordance for vascular (0.72 [95 %CI 0.59 - 0.84]) and inflammatory (0.78 [0.58 - 0.99]) lesions and minimum for polyps (0.46 [0.16 - 0.80]). Blood in the lumen was the only positive finding at capsule endoscopy in 34 cases; of these, 12 had negative DBE findings whereas 10 had vascular lesions, 6 neoplasia, 1 ulcer, and 5 diverticula. CONCLUSION: Capsule endoscopy and DBE have good agreement for vascular and inflammatory lesions but not for polyps or neoplasia. DBE provides valuable adjunctive information, particularly in patients with neoplasia or polyp at capsule endoscopy. DBE clarified the origin of bleeding in two-thirds of patients with capsule endoscopy showing only blood in the lumen.