Factors associated with diagnosis of obscure gastrointestinal bleeding by video capsule enteroscopy

Current status of capsule endoscopy through a whole digestive tract

More than a decade has passed since small-bowel capsule endoscopy (CE) was first reported. Small-bowel CE is a non-invasive tool that allows visualization of the entire small-intestinal mucosa and facilitates detection of small-intestinal abnormalities. Several studies have shown benefit of small-bowel CE for certain disorders. Because it is non-invasive, CE has been applied to other organs including the esophagus, stomach, and colon. The main indications for esophageal CE (ECE) are screening for gastroesophageal reflux disease/Barrett's esophagus, and esophageal varices. However, the clinical benefit of ECE is unconfirmed. Magnetically guided CE (MGCE) was developed to visualize the gastric mucosa. MGCE is a new concept with room for improvement of capsule navigation and the preparation protocol. Recently, two new small-bowel CE tools were released. First-generation colon CE (CCE-1) has moderate sensitivity and specificity compared with colonoscopy for colorectal neoplasia surveillance. To obtain higher accuracy, a second-generation CCE (CCE-2) was developed with a high sensitivity for detecting clinically relevant polypoid lesions. A possible application of CCE is for inflammatory bowel disease. In the near future, CE may include diagnostic and therapeutic functions such as magnifying endoscopy systems, targeted biopsy forceps, and drug delivery systems.

Video capsule endoscopy: Perspectives of a revolutionary technique

Video capsule endoscopy (VCE) was launched in 2000 and has revolutionized direct endoscopic imaging of the gut. VCE is now a first-line procedure for exploring the small bowel in cases of obscure digestive bleeding and is also indicated in some patients with Crohn’s disease, celiac disease, and polyposis syndrome. A video capsule has also been designed for visualizing the esophagus in order to detect Barrett’s esophagus or esophageal varices. Different capsules are now available and differ with regard to dimensions, image acquisition rate, battery life, field of view, and possible optical enhancements. More recently, the use of VCE has been extended to exploring the colon. Within the last 5 years, tremendous developments have been made toward increasing the capabilities of the colon capsule. Although colon capsule cannot be proposed as a first-line colorectal cancer screening procedure, colon capsule may be used in patients with incomplete colonoscopy or in patients who are unwilling to undergo colonoscopy. In the near future, new technological developments will improve the diagnostic yield of VCE and broaden its therapeutic capabilities.

Wireless capsule endoscopy: Perspectives beyond gastrointestinal bleeding

Wireless capsule endoscopy (CE) is a technology developed for the endoscopic exploration of the small bowel. The first capsule model was approved by the Food and Drug Administration in 2001, and its first and essential indication was occult gastrointestinal (GI) bleeding. Over subsequent years, this technology has been refined to provide superior resolution, increased battery life, and capabilities to view different parts of the GI tract. Indeed, cases for which CE proved useful have increased significantly over the last few years, with new indications for the small bowel and technical improvements that have expanded its use to other parts of the GI tract, including the esophagus and colon. The main challenges in the development of CE are new devices with the ability to provide therapy, air inflation for a better vision of the small bowel, biopsy sampling systems attached to the capsule and the possibility to guide and move the capsule with an external motion control. In this article we review the current and new indications of CE, and the evolving technological changes shaping this technology, which has a promising potential in the coming future of gastroenterology.

Capsule endoscopy: Present status and future expectation

Video capsule endoscopy (CE) since its introduction 13 years back, has revolutionized our approach to small intestinal diseases. Obscure gastrointestinal bleed (OGIB) continues to be the most important indication for CE with a high sensitivity, specificity as well as positive and negative predictive values. It is best performed during ongoing bleed or immediately thereafter. Overt OGIB has a higher diagnostic yield than occult OGIB. However, even in iron deficiency anemia, CE is emerging as important investigation after initial negative work up. In suspected Crohn’s disease (CD), CE has been shown superior to traditional imaging and endoscopic technique and should be considered after a negative ileocolonoscopy. Although CE has also been used for evaluating established CD, a high capsule retention rate precludes its use ahead of cross-sectional imaging. Celiac disease, particularly where gastro-duodenoscopy cannot be performed or is normal, can also be investigated by CE. Small bowel tumor, hereditary polyposis syndrome, and non-steroidal anti-inflammatory drugs induced intestinal damage are other indications for CE. Capsule retention is the only significant adverse outcome of CE and occurs mostly in presence of intestinal obstruction. This can be prevented by use of Patency capsule prior to CE examination. Presence of cardiac pacemaker and intracardiac devices continue to be relative contraindications for CE, though data do not suggest interference of CE with these devices. Major limitations of CE today include failure to control its movement from outside, inability of CE to acquire tissue for diagnosis, and lack of therapeutic help. With ongoing interesting and exciting developments taking place in these areas, these issues would be solved in all probability in near future. CE has the potential to become one of the most important tools in diagnostic and possibly in the therapeutic field of gastrointestinal disorder.

Capsule endoscopy for obscure gastrointestinal bleeding in patients with comorbid rheumatic diseases

Background and Aim. We evaluated the association between patients with rheumatic diseases (RD) suffering from obscure gastrointestinal bleeding (OGIB) and positive capsule endoscopy (CE) findings. Methods. All CE procedures performed on patients with RD and OGIB were assessed from a large database at St. Paul's Hospital (Vancouver, BC, Canada) between December 2001 and April 2011. A positive finding on CE was defined as any pathology, including ulcers/erosions, vascular lesions, and mass lesions, perceived to be the source of bleeding. Results. Of the 1133 CEs performed, 41 (4%) complete CEs were for OGIB in patients with RD. Of these, 54% presented with overt bleeding. Mean age was 66 years. Positive findings were seen in 61% of patients. Ulcerations/erosions (36%) and vascular lesions (36%) were the most common findings. Significant differences between the RD versus non-RD populations included: inpatient status, nonsteroidal anti-inflammatory drug (NSAIDs) use, oral steroid use, and mean Charlson index score (all P ≤ 0.008). Similar nonsignificant trends were seen between positive and negative CEs among the RD population. Conclusions. The correlation between RD and positive CE findings is likely influenced by ongoing anti-inflammatory drug use, poorer health status, and a predisposition for angiodysplastic lesions.

The management of lower gastrointestinal bleeding

Lower gastrointestinal (LGI) bleeding is generally less severe than upper gastrointestinal (UGI) bleeding with spontaneous cessation of bleeding in 80% of cases and a mortality of 2-4%. However, unlike UGI bleeding, there is no consensual agreement about management. Once the patient has been stabilized, the main objective and greatest difficulty is to identify the location of bleeding in order to provide specific appropriate treatment. While upper endoscopy and colonoscopy remain the essential first-line examinations, the development and availability of angiography have made this an important imaging modality for cases of active bleeding; they allow diagnostic localization of bleeding and guide subsequent therapy, whether therapeutic embolization, interventional colonoscopy or, if other techniques fail or are unavailable, surgery directed at the precise site of bleeding. Furthermore, newly developed endoscopic techniques, particularly video capsule enteroscopy, now allow minimally invasive exploration of the small intestine; if this is positive, it will guide subsequent assisted enteroscopy or surgery. Other small bowel imaging techniques include enteroclysis by CT or magnetic resonance imaging. At the present time, exploratory surgery is no longer a first-line approach. In view of the lesser gravity of LGI bleeding, it is most reasonable to simply stabilize the patient initially for subsequent transfer to a specialized center, if minimally invasive techniques are not available at the local hospital. In all cases, the complexity and diversity of LGI bleeding require a multidisciplinary collaboration involving the gastroenterologist, radiologist, intensivist and surgeon to optimize diagnosis and treatment of the patient.

Wireless capsule endoscopy

Over the last decade, WCE has established itself as a valuable test for imaging the small intestine. It is a safe and relatively easy procedure to perform that can provide valuable information in the diagnosis of small-bowel conditions. Its applications still remain limited within the esophagus and colon. Future developments may include improving visualization within the esophagus and developing technologies that may allow manipulation of the capsule within the GI tract and biopsy capabilities.

Characteristics of the small bowel lesions detected by capsule endoscopy in patients with chronic kidney disease

Obscure gastrointestinal bleeding (OGIB) is one of the common complications in patients with chronic kidney disease (CKD), especially those who are on maintenance hemodialysis (HD). However, little is known about the characteristics of the small-bowel lesions in these patients, or of the factors that could predict the presence of such lesions. Therefore we enrolled a total of 42 CKD patients (including 19 HD patients and 23 non-HD patients), and compared the incidence of the small-bowel lesions among two groups. Furthermore, to identify predictive factors for the presence of small-bowel lesions, we performed multivariate logistic-regression-analyses. The incidence of small-bowel vascular lesions was significantly higher in CKD patients than in age-and-sex matched non-CKD patients (P < 0.001). On the other hand, there was any significant difference of the incidence of small-bowel lesions between HD and non-HD patients. In CKD patients, past history of blood transfusion (OR 5.66; 95% CI 1.10–29.1, P = 0.04) was identified as an independent predictor of the presence of vascular lesions, and history of low-dose aspirin use (OR 6.00; 95% CI 1.13–31.9, P = 0.04) was identified as that of erosive/ulcerated lesions. This indicated that proactive CE examination would be clinically meaningful for these patients.