What is the Role of Double-Balloon Endoscopy in Patients Presenting with Obscure Gastrointestinal Bleeding?

Small bowel lesions were very difficult to diagnose up until the development of video capsule endoscopy (VCE). It had been regarded as a ‘no man’s area’ in many cases. Although VCE was developed to observe the small bowel lesions, it is difficult to observe in detail the lesion desired by the operator. Moreover, using VCE, it is difficult to perform a biopsy or to treat small bowel lesions. In particular, it is difficult to cope with an emergency situation in patients with gastrointestinal bleeding. A double balloon endoscopy (DBE) has been developed in 2001 by Yamamoto et al, and it has been useful to diagnose and treat small bowel diseases. DBE is advantageous over VCE with respect to the diagnostic and therapeutic capabilities, including tissue sampling, tattooing, hemostasis, endoscopic mucosal resection, balloon dilation, and retention material removal. Obscure gastrointestinal bleeding (OGIB) refers to a state in which unknown origin bleeding or iron deficiency anemia is repeated or persistent after a negative evaluation, including upper gastrointestinal endoscopy and colonoscopy. OGIB can be classified into overt OGIB and occult OGIB. It is important to distinguish between overt bleeding and occult bleeding, because they show different clinical courses and different treatment strategies. OGIB is not an uncommon problem encountered by gastroenterologists, since this may account for 5%–10% of all patients with gastrointestinal bleeding. OGIB usually occurs from lesions in the small bowel. Angiodysplasia is the most common cause of small bowel bleeding, accounting for about 70% of cases. The introduction of VCE and DBE has led to a major advance in the diagnosis and treatment of OGIB. The diagnostic yield of VCE and DBE in OGIB has been reported variously, depending on the different definitions of positive findings as well as on the type of bleeding investigated. Several studies have compared the yield of VCE and DBE, but have shown inconsistent results due to the small sample size. Arakawa et al. reported that a comparison of the overall diagnostic yield between VCE (54%) and DBE (64%) was not significantly different. They insisted that a complementary combination between VCE and DBE was useful for the management of OGIB. In other words, these two procedures should be considered complimentary and not competitive in the diagnosis and treatment of OGIB. Shishido et al. compared VCE-based and DBE-based detections of small bowel lesions in patients with OGIB and showed that small bowel lesions were detected by VCE in 44.9% and by DBE in 53.4% (p=0.01); agreement between VCE and DBE findings was good (κ=0.76). Several investigators compared the diagnostic yields according to the type of OGIB and the timing of the procedures. For patients with prior overt OGIB, the diagnostic yield was less than that for current overt OGIB, which decreased substanReceived: January 19, 2017 Accepted: January 21, 2017 Correspondence: Kwang An Kwon Department of Internal Medicine, Gachon University Gil Hospital, 21 Namdong-daero 774 beon-gil, Namdong-gu, Incheon 21565, Korea Tel: +82-2-32-460-3778, Fax: +82-2-32-460-3408, E-mail: [email protected]