Bleeding from the small intestine remains a relatively uncommon event, accounting for ~5-10% of all patients presenting with gastrointestinal (GI) bleeding. Given advances in small bowel imaging with video capsule endoscopy (VCE), deep enteroscopy, and radiographic imaging, the cause of bleeding in the small bowel can now be identified in most patients. The term small bowel bleeding is therefore proposed as a replacement for the previous classification of obscure GI bleeding (OGIB). We recommend that the term OGIB should be reserved for patients in whom a source of bleeding cannot be identified anywhere in the GI tract. A source of small bowel bleeding should be considered in patients with GI bleeding after performance of a normal upper and lower endoscopic examination. Second-look examinations using upper endoscopy, push enteroscopy, and/or colonoscopy can be performed if indicated before small bowel evaluation. VCE should be considered a first-line procedure for small bowel investigation. Any method of deep enteroscopy can be used when endoscopic evaluation and therapy are required. VCE should be performed before deep enteroscopy if there is no contraindication. Computed tomographic enterography should be performed in patients with suspected obstruction before VCE or after negative VCE examinations. When there is acute overt hemorrhage in the unstable patient, angiography should be performed emergently. In patients with occult hemorrhage or stable patients with active overt bleeding, multiphasic computed tomography should be performed after VCE or CTE to identify the source of bleeding and to guide further management. If a source of bleeding is identified in the small bowel that is associated with significant ongoing anemia and/or active bleeding, the patient should be managed with endoscopic therapy. Conservative management is recommended for patients without a source found after small bowel investigation, whereas repeat diagnostic investigations are recommended for patients with initial negative small bowel evaluations and ongoing overt or occult bleeding.

Obscure gastrointestinal bleeding is still a clinical challenge for gastroenterologists. The recent development of novel technologies for the diagnosis and treatment of different bleeding causes has allowed a better management of patients, but it also determines the need of a deeper comprehension of pathophysiology and the analysis of local expertise in order to develop a rational management algorithm. Obscure gastrointestinal bleeding can be divided in occult, when a positive occult blood fecal test is the main manifestation, and overt, when external sings of bleeding are visible. In this paper we are going to focus on overt gastrointestinal bleeding, describing the physiopathology of the most usual causes, analyzing the diagnostic procedures available, from the most classical to the novel ones, and establishing a standard algorithm which can be adapted depending on the local expertise or availability. Finally, we will review the main therapeutic options for this complex and not so uncommon clinical problem.

Within the last decade, the technological development improved the diagnostic work-up of small bowel diseases. In addition to abdominal ultrasound and radiological methods, the importance of endoscopy is increasing. Nowadays, five nonsurgical flexible endoscopy techniques are available for small bowel endoscopy: push enteroscopy and balloon-guided enteroscopy for evaluation of the proximal small bowel, balloon-assisted enteroscopy using two balloons (double-balloon enteroscopy) or one balloon (single-balloon enteroscopy), and spiral enteroscopy for evaluation of the deep small bowel. Intraoperative enteroscopy has become a reserve method.

Nowadays, 5 nonsurgical flexible endoscopic techniques are available for small bowel endoscopy: push enteroscopy (PE), balloon-assisted enteroscopy using 2 balloons (double-balloon enteroscopy [DBE]) or 1 balloon (single-balloon enteroscopy [SBE]), balloon-guided enteroscopy (BGE), and spiral enteroscopy (SE). PE is a cost-saving, easy, and fast procedure for the examination of the proximal jejunum, but for a deep small bowel endoscopy, the other flexible enteroscopic techniques are required. BGE does not play a considerable role in deep small bowel endoscopy. DBE is the oldest flexible enteroscopic technique. Actually, the balloon-assisted enteroscopy (BAE) techniques with one balloon (SBE) or two balloons (DBE) are the mainly used techniques. DBE has become established throughout the world for diagnostic and therapeutic examinations of the small bowel and is now used universally in clinical routine work. DBE is still regarded as the gold standard nonsurgical procedure for deep small bowel endoscopy, because it provides the highest rates of complete enteroscopy, which becomes increasingly useful. The recently introduced SE technique represents a promising method but still needs technical improvement. Larger prospective studies on SE and prospective studies comparing the 3 systems (DBE, SBE, SE) are awaited before conclusive assessments can be made.

Small bowel endoscopy has made tremendous advances over the last 8 years. The introduction of capsule endoscopy, double-balloon enteroscopy, single-balloon enteroscopy and spiral overtube-assisted enteroscopy have completely removed the mystery in investigating the small intestine. These new procedures are challenging and timeconsuming to perform. A brief overview on the technical issues and complications related to these small bowel endoscopy procedures is presented.

To evaluate the diagnostic yield of push enteroscopy in relation to indication and compare the yield in patients who had capsule endoscopy followed by push enteroscopy against capsule endoscopy naive patients.

With the advent of capsule endoscopy the role of push enteroscopy needs to be reevaluated.

Patients who underwent push enteroscopy from January 2002 to May 2006 were included.

One hundred fifty-five patients underwent push enteroscopy: 93 females, average age 55 years. There were 74 cases where both push enteroscopy (PE) and capsule endoscopy (CE) were performed. Indications for PE were iron deficiency anemia (n=51), overt bleeding (n=31), suspected celiac disease (n=32), refractory celiac disease (n=19), assessment for Crohn's disease (n=10), and miscellaneous (n=12). In 148 patients, an average length of 70 cm of small bowel was examined (range 30 to 130 cm). PE was unsuccessful in 7 patients due to anatomic strictures or patient distress. The overall diagnostic yield was 30% with the highest yield in overt bleeding when compared with other subgroups (P<0.001). Nine percent of lesions were within the reach of a standard endoscope. Comparison of the diagnostic yield in patients who had CE followed by PE against CE naive patients was 41% versus 47%, respectively (P<1). There were no cases where push enteroscopy recognized a lesion that had not been already detected by capsule endoscopy.

Push enteroscopy has the greatest diagnostic yield in patients with overt bleeding when compared with other referral indications. PE should be used as an adjuvant to CE for therapeutic intervention.

This literature review and the recommendations therein were prepared for the AGA Institute Clinical Practice and Economics Committee. The paper was approved by the Committee on March 12, 2007, and by the AGA Institute Governing Board on May 19, 2007.

Push enteroscopy has not been compared to standard endoscopy in children.

The aim of this study was to determine the feasibility of push enteroscopy in children with suspected proximal small bowel disease, and to compare its diagnostic yield and safety with standard endoscopy.

Database review.

A database analysis was performed on all children who underwent push enteroscopy at The Johns Hopkins Children's Center from 2001 to 2005. Patient demographics, clinical history, and indication for push enteroscopy were all recorded. Clinical utility was qualified based on the influence of PE on therapy.

Diagnostic yield and safety of push enteroscopy in children.

Push enteroscopy was performed on 44 children (27 M; 17 F) with a median age (range) of 10 (2-18) years. The most common indications for push enteroscopy were suspected proximal small bowel disease based on radiological criteria (21), and bleeding (9). Push enteroscopy confirmed the diagnosis of proximal small bowel Crohn's disease (CD) in 23, polyps in 5, eosinophilic gastroenteritis in 4, celiac disease in 1, microvillous inclusion disease in 1, and lymphoproliferative disease in 1 patient. An isolated non-Crohn's related gastric (1) and jejunal ulcer (1) was also identified. Just 9 of these identifiable lesions were within reach by esophagogastroduodenoscopy (EGD). Seven patients had a normal push enteroscopy. The clinical management was modified in 34 patients. Push enteroscopy was not shown to significantly alter the time of procedure when compared to EGD.

Push enteroscopy is a safe diagnostic tool with proven clinical utility in children with suspected proximal small bowel disease. Larger studies are needed to establish the widespread application of push enteroscopy in pediatrics.

Obscure GI bleeding is a relatively common problem facing internists, gastroenterologists, and surgeons in a typical clinical practice. The etiology is occasionally suggested by the patient's age, history, and medications. Management is complicated and typically requires a team-oriented approach, with input from the internist, gastroenterologist, radiologist, and surgeon alike. SBFT and enteroclysis seem to have a limited role, unless there is a high suspicion of a small bowel mass lesion or Crohn's disease. Scintigraphy may be performed in patients with active bleeding in whom endoscopy has failed oris contraindicated. Angiography may be used in patients with an early positive nuclear imaging or failed endoscopic therapy. Provocative angiography probably has a lower diagnostic yield than previously reported, and should be performed only in experienced centers. Helical CT is a new and potentially important option in patients with obscure bleeding, but is currently considered experimental. All patients with obscure GI bleeding should undergo repeat upper endoscopy and perhaps colonoscopy to rule out missed lesions. SBE seems to be complementary to capsule endoscopy, and it is unknown whether this should be performed before capsule endoscopy or only if capsule endoscopy yields a positive proximal small bowel finding. Double balloon enteroscopy seems promising, but the technique requires further study. Surgery should be reserved for patients who have a positive capsule endoscopy requiring surgical therapy or patients who have persistent GI bleeding requiring recurrent blood transfusions in whom all other modalities have failed. Treatment for vascularectasias, the most common cause of obscure GI bleeding, is currently inadequate,and typically requires a combination of multiple management approaches.

Although enteroscopy has been increasingly used to investigate occult or obscure bleeding, little is known about its impact on patient management. The aim of the present paper was to evaluate both the diagnostic yield and the impact of push enteroscopy on the management of patients referred to a tertiary Australian institution.

Data were collected prospectively in all patients undergoing push enteroscopy at Royal Adelaide Hospital. Fifty-five patients were investigated for obscure gastrointestinal (GI) bleeding (25 women, mean age 65.6 years), the cause of which remained unknown despite previous gastroscopy and colonoscopy. The patients were divided into two groups: occult-obscure (anemia without macroscopic blood loss) and overt-obscure (macroscopic bleeding). Findings at enteroscopy, therapeutic procedures, and complications were recorded. Patients were followed to establish the impact of the procedure on subsequent management and clinical outcome.

Enteroscopy demonstrated a potential site of bleeding in 38 patients (69%), and 38% of lesions found were within the reach of the gastroscope. The most common lesions were small intestinal angiodysplasia. Seventy-five percent of patients with positive findings had alterations to their management. After subsequent treatment, 62% were no longer anemic and there was a significant reduction in rebleeding (P < 0.05) and transfusion requirements (P < 0.05) compared to patients with negative findings. The procedure was well tolerated and complications were rare.

Enteroscopy has a positive impact on patient management and clinical outcome in a majority of patients with obscure gastrointestinal bleeding.

The management of patients with small bowel bleeding remains a diagnostic and therapeutic challenge. In most gastrointestinal bleeding episodes, the source of hemorrhage is localized to either the upper gastrointestinal tract or colon; however, in about 5% of cases, upper endoscopy and colonoscopy are nondiagnostic, and the small intestine is the site of bleeding. Patients with suspected small bowel source of bleeding may present with either occult blood loss or recurrent overt gastrointestinal hemorrhage requiring frequent blood transfusions and hospitalizations. Knowing the etiology and site of hemorrhage is essential prior to initiating appropriate therapy. The most common causes of small bowel bleeding are vascular ectasia, tumors, ulcerative diseases, and Meckel's diverticula. For patients with severe obscure bleeding, push enteroscopy with a 220- to 250-cm enteroscope is strongly recommended. This procedure provides not only a thorough examination for diagnosis, but also allows for biopsy, tattooing, and hemostasis of lesions. If enteroscopy is nondiagnostic, capsule endoscopy is recommended. A diagnostic capsule endoscopy will direct appropriate medical, endoscopic, or surgical intervention, depending on whether the lesion is single or multiple, and whether the patient is a surgical candidate for intraoperative enteroscopy. Intraoperative enteroscopy should be strongly considered in patients with recurrent bleeding and a nondiagnostic evaluation. Laparoscopy and intraoperative enteroscopy is highly recommended in young patients (< 50 years of age) because there is an increased frequency of small bowel tumors and Meckel's diverticulum which are amenable to surgical therapy.

The identification and treatment of lesions located in the small intestine in obscure gastrointestinal bleeding is always a clinical challenge.

To examine prospectively the diagnostic precision and the clinical efficacy of capsule endoscopy compared with push enteroscopy in obscure gastrointestinal bleeding.

Forty-two patients (22 men and 20 women) with obscure gastrointestinal bleeding (overt bleeding in 26 cases and occult blood loss with chronic anaemia in 16) and normal oesophagogastroduodenoscopy and colonoscopy were analysed. All patients were instructed to receive the capsule endoscopy and push enteroscopy was performed within the next 7 days. Both techniques were blindly performed by separate examiners. The diagnostic yield for each technique was defined as the frequency of detection of clinically relevant intestinal lesions carrying potential for bleeding.

A bleeding site potentially related to gastrointestinal bleeding or evidence of active bleeding was identified in a greater proportion of patients using capsule endoscopy (74%; 31 of 42) than enteroscopy (19%; eight of 42) (P = 0.05). The most frequent capsule endoscopy findings were: angiodysplasia (45%), fresh blood (23%), jejunal ulcers (10%), ileal inflammatory mucosa (6%) and ileal tumour (6%). No additional intestinal diagnoses were made by enteroscopy. In seven patients (22%), the results obtained with capsule endoscopy led to a successful change in the therapeutic approach.

Compared with push enteroscopy, capsule endoscopy increases the diagnosis yield in patients with obscure gastrointestinal bleeding, and allows modification on therapy strategy in a remarkable proportion of patients.

The identification and localization of lesions located in the small intestine that may provoke gastrointestinal bleeding is difficult.

To analyze the role of capsule endoscopy in patients with obscure digestive bleeding and to compare the results obtained with those of enteroscopy.

Twenty-one patients with obscure digestive bleeding (acute hemorrhage in 11 patients and chronic anemia in 10) and normal total fibergastroscopy and fibrocolonoscopy were analyzed. All patients were instructed to receive the capsule and enteroscopy was performed after 1 week. The results obtained using both procedures were independently compared and without knowledge of the results of the other procedure.

Visualization of findings potentially related to gastrointestinal bleeding was significantly greater (p < 0.05) using the capsule (14 of 21 patients [66%]) than with enteroscopy (4 of 21 patients [19%]). The most frequent lesions were angiodysplasias and jejunal ulcers. In 4 patients, the results obtained led to a change in therapeutic approach. One patient with jejunal stenosis and two with ileal lesions underwent surgery, which confirmed the diagnosis of Crohn's disease in the first patient and carcinoid tumor in the remaining two. Another patient with evidence of angiodysplasia and bleeding was effectively treated with Argon-beam during enteroscopy. The capsule was well tolerated in all patients. In the patient with jejunal stenosis, capsule extraction was required during surgery.

Capsule endoscopy allows adequate visualization of the entire small intestine and its diagnostic efficacy is greater than that of enteroscopy in patients with obscure digestive bleeding. Moreover, in our series, this procedure allowed modification of therapy in one out of every five patients.