Use and Misuse of Small Bowel Video Capsule Endoscopy in Clinical Practice

Abstract

Video capsule endoscopy (VCE) was introduced into the United States in 2000 and has significantly advanced the ability to visualize the small intestinal mucosa by using noninvasive technology. Compared with traditional imaging with small bowel barium imaging, the use of VCE has demonstrated the ability to enhance diagnostic yield in patients with suspected small bowel pathology by approximately 25%–50% in patients with suspected small bowel disorders.1Costamagna G. Shah S.K. Riccioni M.E. et al.A prospective trial comparing small bowel radiographs and video capsule endoscopy for suspected small bowel disease.Gastroenterology. 2002; 123: 999-1005Abstract Full Text Full Text PDF PubMed Scopus (780) Google Scholar, 2Hara A.K. Leighton J.A. Sharma V.K. et al.Small bowel: preliminary comparison of capsule endoscopy with barium study and CT.Radiology. 2004; 230: 260-265Crossref PubMed Scopus (252) Google Scholar, 3Laine L. Sahota A. Shah A. Does capsule endoscopy improve outcomes in obscure gastrointestinal bleeding? Randomized trial versus dedicated small bowel radiography.Gastroenterology. 2010; 138: 1673-1680Abstract Full Text Full Text PDF PubMed Scopus (84) Google Scholar Although the use of VCE has been recommended as the next step in patients with obscure gastrointestinal hemorrhage after a negative upper and/or lower endoscopic examination,4Raju G.S. Gerson L. Das A. et al.American Gastroenterological Association (AGA) Institute technical review on obscure gastrointestinal bleeding.Gastroenterology. 2007; 133: 1697-1717Abstract Full Text Full Text PDF PubMed Scopus (400) Google Scholar its use in other clinical scenarios such as small bowel inflammatory disorders may not be associated with similar diagnostic yields. The major complication associated with the use of VCE remains small bowel retention. Although the risk of this event is virtually nil in patients with obscure bleeding, it can approach 10% in patients with known inflammatory bowel disease (IBD).5Cheifetz A.S. Kornbluth A.A. Legnani P. et al.The risk of retention of the capsule endoscope in patients with known or suspected Crohn's disease.Am J Gastroenterol. 2006; 101: 2218-2222Crossref PubMed Scopus (300) Google Scholar A critical appraisement of appropriate use of this technology may help physicians and third-party payers to determine which subset of patients with suspected or known small bowel disorders would benefit the most from undergoing a VCE procedure. To critically examine the use of VCE in clinical practice, an evidence-based approach was performed by using the GRADE system,6Atkins D. Best D. Briss P.A. et al.Grading quality of evidence and strength of recommendations.BMJ. 2004; 328: 1490-1494Crossref PubMed Google Scholar, 7Atkins D. Briss P.A. Eccles M. et al.Systems for grading the quality of evidence and the strength of recommendations II: pilot study of a new system.BMC Health Serv Res. 2005; 5: 25-36Crossref PubMed Scopus (247) Google Scholar and a critical review of the literature on capsule endoscopy was performed by using PubMed, SCOPUS, and the Cochrane Database from 2000–2012. The quality of evidence could range from high (implying that further research was unlikely to change the authors' confidence in the estimate of the effect) to moderate (further research would be likely to have an impact on the confidence in the estimate of effect) or low (further research would be expected to have an important impact on the confidence in the estimate of the effect and would be likely to change the estimate). The strength of a recommendation was graded as strong when the desirable effects of an intervention clearly outweigh the undesirable effects and as conditional when there was uncertainty about the tradeoffs. The evidence-based statements generated from this review are shown in Table 1. Studies including more than 20 patients were included for each topic to increase data quality when meta-analyses or randomized controlled trials were not available.Table 1Evidence-based Recommendations for Use of VCERecommendations for use of VCE Obscure gastrointestinal hemorrhage VCE should be performed for evaluation of obscure bleeding as the next diagnostic test after normal upper and lower endoscopic examinations. (Strong recommendation, high level of evidence) For patients with obscure overt bleeding, VCE should be administered as soon as feasible to increase the diagnostic yield. (Strong recommendation, high level of evidence) In patients with IDA, VCE should be performed for further evaluation after negative upper endoscopic and colonoscopic examinations. (Strong recommendation, high level of evidence) IBD VCE is recommended in patients with suspected or known Crohn's disease after negative ileoscopy in patients without signs or symptoms of obstruction. (Strong recommendation, high level of evidence) In patients with suspected obstruction, patency VCE or enterography examination should occur as the next diagnostic test. (Conditional recommendation, moderate level of evidence) VCE should not be routinely performed after a normal IC and MRE/CTE examination because of the low diagnostic yield for Crohn's disease. (Conditional recommendation, moderate level of evidence) Celiac disease VCE can be considered as an alternative test to histology for the diagnosis of celiac disease. (Conditional recommendation, moderate level of evidence) VCE should be performed in patients with nonresponsive celiac disease to assess for disease-associated complications. (Conditional recommendation, moderate level of evidence) Hereditary polyposis In patients with PJS, small bowel surveillance with VCE should occur starting at the age of 8 years and continuing every 3 years. (Conditional recommendation, low level of evidence) Screening for distal polyps by VCE can be considered in patients with FAP who have evidence of duodenal polyps on side-viewing endoscopic examination. (Conditional recommendation, low level evidence)Potential misuse of capsule endoscopy Chronic abdominal pain or isolated diarrhea VCE is not recommended in patients with isolated abdominal pain or diarrhea without the presence of inflammatory markers. (Conditional recommendation, moderate level of evidence) VCE should not be performed to evaluate isolated weight loss. (Conditional recommendation, low level of evidence) Scenarios with high risk of retention VCE should be avoided in clinical scenarios with increased risks of capsule retention including known IBD and radiation enteritis. (Conditional recommendation, moderate level of evidence) Open table in a new tab The use of VCE has been demonstrated to be superior compared with use of small bowel radiography, push enteroscopy (PE), or computed or magnetic enterography for visualization of small bowel sources of overt hemorrhage or iron deficiency anemia (IDA). Bleeding from a small bowel source remains uncommon, accounting for approximately 5% of sources in patients presenting with overt or occult gastrointestinal hemorrhage.4Raju G.S. Gerson L. Das A. et al.American Gastroenterological Association (AGA) Institute technical review on obscure gastrointestinal bleeding.Gastroenterology. 2007; 133: 1697-1717Abstract Full Text Full Text PDF PubMed Scopus (400) Google Scholar In patients with suspected small intestinal disorders, the yield of capsule endoscopy has been estimated to be approximately 60%. Capsule endoscopy is preferred as the initial test compared to deep enteroscopy because of its ability to visualize the entire small bowel, a decreased potential for complications, and decreased use of endoscopic resources.8Gerson L. Kamal A. Cost-effectiveness analysis of management strategies for obscure GI bleeding.Gastrointest Endosc. 2008; 68: 920-936Abstract Full Text Full Text PDF PubMed Scopus (99) Google Scholar On the basis of this information, use of VCE has been recommended as the next step in the evaluation of patients with gastrointestinal hemorrhage after a normal upper and lower endoscopic examination.9Pennazio M. Eisen G. Goldfarb N. ICCE consensus for obscure gastrointestinal bleeding.Endoscopy. 2005; 37: 1046-1050Crossref PubMed Scopus (146) Google Scholar The caveat of this recommendation is that approximately 20%–30% of patients will have sources of bleeding detected within reach of a standard endoscope or colonoscope on repeat examination that were not detected on initial examination. This finding has been demonstrated in patients undergoing both capsule endoscopy10Robinson C.A. Jackson C. Condon D. et al.Impact of inpatient status and gender on small-bowel capsule endoscopy findings.Gastrointest Endosc. 2011; 74: 1061-1066Abstract Full Text Full Text PDF PubMed Scopus (39) Google Scholar and deep enteroscopy.11Fry L.C. Bellutti M. Neumann H. et al.Incidence of bleeding lesions within reach of conventional upper and lower endoscopes in patients undergoing double-balloon enteroscopy for obscure gastrointestinal bleeding.Aliment Pharmacol Ther. 2009; 29: 342-349Crossref PubMed Scopus (90) Google Scholar Use of VCE has been demonstrated to be clearly superior to other imaging modalities for the small bowel in patients with obscure bleeding. Based on the prior literature, VCE offers an increased diagnostic yield of 25%–50% compared to the yield demonstrated by using traditional small bowel radiography1Costamagna G. Shah S.K. Riccioni M.E. et al.A prospective trial comparing small bowel radiographs and video capsule endoscopy for suspected small bowel disease.Gastroenterology. 2002; 123: 999-1005Abstract Full Text Full Text PDF PubMed Scopus (780) Google Scholar, 2Hara A.K. Leighton J.A. Sharma V.K. et al.Small bowel: preliminary comparison of capsule endoscopy with barium study and CT.Radiology. 2004; 230: 260-265Crossref PubMed Scopus (252) Google Scholar (yield, 3%–20%), PE (yield, 3%–30%),12Lewis B.S. Swain P. Capsule endoscopy in the evaluation of patients with suspected small intestinal bleeding: results of a pilot study.Gastrointest Endosc. 2002; 56: 349-353Abstract Full Text Full Text PDF PubMed Scopus (529) Google Scholar, 13Mylonaki M. Fritscher-Ravens A. Swain P. Wireless capsule endoscopy: a comparison with push enteroscopy in patients with gastroscopy and colonoscopy negative gastrointestinal bleeding.Gut. 2003; 52: 1122-1126Crossref PubMed Scopus (471) Google Scholar, 14Pennazio M. Santucci R. Rondonotti E. et al.Outcome of patients with obscure gastrointestinal bleeding after capsule endoscopy: report of 100 consecutive cases.Gastroenterology. 2004; 126: 643-653Abstract Full Text Full Text PDF PubMed Scopus (853) Google Scholar and/or elective angiography (5%–15%).15Defreyne L. Uder M. Vanlangenhove P. et al.Angiography for acute lower gastrointestinal hemorrhage: efficacy of cut film compared with digital subtraction techniques.J Vasc Interv Radiol. 2003; 14: 313-322Abstract Full Text Full Text PDF PubMed Scopus (16) Google Scholar, 16Berjljung L. Hjorth S. Svendler C.A. et al.Angiography in acute gastrointestinal bleeding.Surg Gynecol Obstet. 1977; 145: 501-503PubMed Google Scholar In patients with a negative capsule endoscopy, the use of multidetector computed tomographic enterography (CTE) or magnetic resonance enterography (MRE) has been shown to detect pathology in some patients, particularly if bleeding is related to an underlying neoplasm.17Hakim F.A. Alexander J.A. Huprich J.E. et al.CT-enterography may identify small bowel tumors not detected by capsule endoscopy: eight years experience at Mayo Clinic Rochester.Dig Dis Sci. 2011; 56: 2914-2919Crossref PubMed Scopus (88) Google Scholar Timing of the VCE examination has been demonstrated to be associated with diagnostic yield in patients with overt obscure hemorrhage. In a landmark study published by Pennazio et al14Pennazio M. Santucci R. Rondonotti E. et al.Outcome of patients with obscure gastrointestinal bleeding after capsule endoscopy: report of 100 consecutive cases.Gastroenterology. 2004; 126: 643-653Abstract Full Text Full Text PDF PubMed Scopus (853) Google Scholar in 2004, the diagnostic yield in 100 patients undergoing VCE was 92% in patients with ongoing overt hemorrhage, 13% in patients with bleeding that had stopped (intervals ranging between 10 days and 1 year), and 44% in the IDA cohort. Subsequent studies defined higher diagnostic yields when VCE was performed within 2 weeks of an overt bleeding episode (detection rate, 91%) compared with 34% when the VCE occurred more than 2 weeks later.18Bresci G. Parisi G. Bertoni M. et al.The role of video capsule endoscopy for evaluating obscure gastrointestinal bleeding: usefulness of early use.J Gastroenterol. 2005; 40: 256-259Crossref PubMed Scopus (130) Google Scholar Similarly higher diagnostic rates have been demonstrated when deep enteroscopy is performed within 2 weeks of an overt bleeding episode.19Shinozaki S. Yamamoto H. Yano T. et al.Long-term outcome of patients with obscure gastrointestinal bleeding investigated by double-balloon endoscopy.Clin Gastroenterol Hepatol. 2010; 8: 151-158Abstract Full Text Full Text PDF PubMed Scopus (105) Google Scholar For inpatients, the yield of VCE has been shown to exceed 90% when administered within 48 hours of hospital admission.20Apostolopoulos P. Liatsos C. Gralnek I.M. et al.Evaluation of capsule endoscopy in active, mild-to-moderate, overt, obscure GI bleeding.Gastrointest Endosc. 2007; 66: 1174-1181Abstract Full Text Full Text PDF PubMed Scopus (75) Google Scholar However, although associated with higher diagnostic yields, use of VCE in the inpatient setting carries increased rates of gastric retention and incomplete examinations to the cecum.10Robinson C.A. Jackson C. Condon D. et al.Impact of inpatient status and gender on small-bowel capsule endoscopy findings.Gastrointest Endosc. 2011; 74: 1061-1066Abstract Full Text Full Text PDF PubMed Scopus (39) Google Scholar In patients at higher risk of incomplete examinations, endoscopic placement into the duodenum and/or administration of prokinetic therapy should be considered. In patients presenting with chronic IDA, performance of VCE is also recommended as the next diagnostic test after a negative upper and lower endoscopic examination.4Raju G.S. Gerson L. Das A. et al.American Gastroenterological Association (AGA) Institute technical review on obscure gastrointestinal bleeding.Gastroenterology. 2007; 133: 1697-1717Abstract Full Text Full Text PDF PubMed Scopus (400) Google Scholar A recent meta-analysis published in 2012 examined the utility of VCE in 1960 patients from 24 studies with IDA.21Koulaouzidis A. Rondonotti E. Giannakou A. et al.Diagnostic yield of small-bowel capsule endoscopy in patients with iron-deficiency anemia: a systematic review.Gastrointest Endosc. 2012; 76: 983-992Abstract Full Text Full Text PDF PubMed Scopus (90) Google Scholar Although the diagnostic yield overall was 47% (95% confidence interval, 42%–52%), there was significant heterogeneity among studies that influenced the results. When only patients with confirmed IDA by established thresholds for hemoglobin and ferritin values were included, the diagnostic yield increased to 67% (95% confidence interval, 61%–72%). Angioectasias accounted for approximately 45% of the positive findings on VCE examinations. The risk of rebleeding after VCE depends on the type of lesion detected and the associated patient comorbidities. Patients with normal VCE examinations have a very low risk (<5%) of rebleeding during the course of the subsequent year.22Lai L.H. Wong G.L. Chow D.K. et al.Long-term follow-up of patients with obscure gastrointestinal bleeding after negative capsule endoscopy.Am J Gastroenterol. 2006; 101: 1224-1228Crossref PubMed Scopus (153) Google Scholar Rebleeding rates can be expected to be highest (>50%) in patients with fresh blood on VCE examination or angiodysplastic lesions. In many patients with small bowel arteriovenous malformations, however, bleeding can subside over time without endoscopic or other therapy.3Laine L. Sahota A. Shah A. Does capsule endoscopy improve outcomes in obscure gastrointestinal bleeding? Randomized trial versus dedicated small bowel radiography.Gastroenterology. 2010; 138: 1673-1680Abstract Full Text Full Text PDF PubMed Scopus (84) Google Scholar, 23Sheibani S. Levesque B.G. Friedland S. et al.Long-term impact of capsule endoscopy in patients referred for iron-deficiency anemia.Dig Dis Sci. 2010; 55: 703-708Crossref PubMed Scopus (21) Google Scholar Patients with comorbid conditions including cardiovascular, renal, and pulmonary disorders are most likely to demonstrate rebleeding from new or existing vascular lesions.24Arakawa D. Ohmiya N. Nakamura M. et al.Outcome after enteroscopy for patients with obscure GI bleeding: diagnostic comparison between double-balloon endoscopy and videocapsule endoscopy.Gastrointest Endosc. 2009; 69: 866-874Abstract Full Text Full Text PDF PubMed Scopus (161) Google Scholar Several studies have assessed further change in management after VCE studies performed for obscure gastrointestinal bleeding. In the original 2004 study published by Pennazio et al,14Pennazio M. Santucci R. Rondonotti E. et al.Outcome of patients with obscure gastrointestinal bleeding after capsule endoscopy: report of 100 consecutive cases.Gastroenterology. 2004; 126: 643-653Abstract Full Text Full Text PDF PubMed Scopus (853) Google Scholar all of the 23 patients with overt bleeding were treated (including medical therapy in 9 patients, endoscopic treatment in 11, and surgery in 3 patients), resulting in a cessation rate of 87% during the follow-up period ranging from 12–25 months. Of the 39 patients with obscure-occult bleeding, 25 patients underwent further examinations after VCE. The diagnosis remained unknown in 17 patients, 18 were treated medically, 5 underwent endoscopic therapy, 6 had surgery, and 10 patients were not treated. Complete resolution in this cohort was 69% during the follow-up period. In a subsequent 2007 study published in the Netherlands by van Tuyl et al,25van Tuyl S.A. van Noorden J.T. Stolk M.F. et al.Clinical consequences of videocapsule endoscopy in GI bleeding and Crohn's disease.Gastrointest Endosc. 2007; 66: 1164-1170Abstract Full Text Full Text PDF PubMed Scopus (15) Google Scholar questionnaires were sent to the treating physicians for 150 patients undergoing VCE for evaluation of obscure bleeding (N = 97), Crohn's disease (N = 36), or other reasons (N = 17). Assessments occurred 1 year after VCE to determine the impact of VCE on subsequent patient management. Management alterations were considered to be present if there was a change in medication, performance of an endoscopic procedure, surgery or other procedure, or avoidance of additional testing. VCE established a definite diagnosis in 51 patients (34%), probable diagnosis in 51 (34%), and no diagnosis in 48 of the patients (32%). Fifty-nine percent of the patients with a definite diagnosis had a change in management, compared with the overall rate of 38%. Despite change in management as a result of the VCE study findings, performance of a VCE study may not change long-term patient outcomes such as resolution or recurrence of bleeding. This is particularly true for patients with small bowel angiodysplastic lesions, in whom rebleeding rates have been shown to exceed 50% at 1 year post-VCE.22Lai L.H. Wong G.L. Chow D.K. et al.Long-term follow-up of patients with obscure gastrointestinal bleeding after negative capsule endoscopy.Am J Gastroenterol. 2006; 101: 1224-1228Crossref PubMed Scopus (153) Google Scholar Long-term outcome studies after deep enteroscopy have demonstrated that patients with small bowel vascular lesions are more likely to experience recurrent bleeding 1 and 3 years after enteroscopy,19Shinozaki S. Yamamoto H. Yano T. et al.Long-term outcome of patients with obscure gastrointestinal bleeding investigated by double-balloon endoscopy.Clin Gastroenterol Hepatol. 2010; 8: 151-158Abstract Full Text Full Text PDF PubMed Scopus (105) Google Scholar, 26Gerson L.B. Batenic M.A. Newsom S.L. et al.Long-term outcomes after double-balloon enteroscopy for obscure gastrointestinal bleeding.Clin Gastroenterol Hepatol. 2009; 7: 664-669Abstract Full Text Full Text PDF PubMed Scopus (105) Google Scholar particularly in the setting of concomitant cardiovascular and/or renal disease.24Arakawa D. Ohmiya N. Nakamura M. et al.Outcome after enteroscopy for patients with obscure GI bleeding: diagnostic comparison between double-balloon endoscopy and videocapsule endoscopy.Gastrointest Endosc. 2009; 69: 866-874Abstract Full Text Full Text PDF PubMed Scopus (161) Google Scholar On the other hand, studies have demonstrated that approximately 30%–40% of patients with angiodysplastic lesions may experience spontaneous cessation of bleeding and/or anemia over time.27Junquera F. Feu F. Papo M. et al.A multicenter, randomized, clinical trial of hormonal therapy in the prevention of rebleeding from gastrointestinal angiodysplasia.Gastroenterology. 2001; 121: 1073-1079Abstract Full Text Full Text PDF PubMed Scopus (182) Google Scholar In a 2010 retrospective study, 82 patients with a history of obscure gastrointestinal bleeding (including IDA in 57 and overt bleeding in 25) were followed for a mean of 36 ± 16 months (IDA cohort) or 40 months (obscure bleeding group).23Sheibani S. Levesque B.G. Friedland S. et al.Long-term impact of capsule endoscopy in patients referred for iron-deficiency anemia.Dig Dis Sci. 2010; 55: 703-708Crossref PubMed Scopus (21) Google Scholar Abnormal findings on VCE were detected in 60% of both cohorts, with angiodysplastic lesions accounting for 40% of the findings. During the mean follow-up period, there was no difference in the percentage of patients who remained anemic (23% of the IDA group vs 22% of the overt group). Of the 35 patients in the IDA referral group with significant VCE pathology, 15 underwent therapeutic procedures, and 20 were managed conservatively. The authors found that most of the patients referred for VCE examination to evaluate IDA were no longer anemic at 36 months of follow-up, with or without therapeutic intervention. The use of VCE for patients with inflammatory disorders of the small bowel has been established. Capsule endoscopy can be used to diagnose IBD in patients with suggestive signs and/or symptoms and can exclude the diagnosis in patients with nonspecific inflammation of the bowel on other imaging modalities. VCE can be used to assess disease activity and/or recurrence in patients with established small bowel Crohn's disease. However, the ability of VCE to distinguish whether ulcerations are a result of IBD compared to other causes such as nonsteroidal anti-inflammatory drugs remains a significant limitation. In a study published in 2005, 39 patients (11 with suspected Crohn's disease and 28 with established disease) underwent VCE, ileocolonoscopy (IC), and either small bowel series (small bowel follow-through [SBFT]) or barium enema examinations to evaluate symptoms. All 3 testing modalities were performed in 11 of 39 patients without a diagnosis of Crohn's disease and in 28 of 39 patients with established disease. A final diagnosis of active Crohn's disease was made in 29 of 39 patients (74%); the diagnosis was made on the basis of endoscopy and histopathology in 25 of 39 patients (64%), VCE in 26 of 39 (67%), and radiographic studies in 8 of 39 (20% with a miss rate of 72%). Overall, VCE had a sensitivity of 90% and specificity of 100% compared with SBFT with a sensitivity of 26% and specificity of 100% for the diagnosis of small bowel Crohn's disease28Dubcenco E. Jeejeebhoy K.N. Petroniene R. et al.Capsule endoscopy findings in patients with established and suspected small-bowel Crohn's disease: correlation with radiologic, endoscopic, and histologic findings.Gastrointest Endosc. 2005; 62: 538-544Abstract Full Text Full Text PDF PubMed Scopus (108) Google Scholar (Table 2).Table 2Sensitivity and Specificity of VCE for Small Bowel DisordersaNumbers shown as sensitivity (specificity) in table.Study, yearNo. of patientsVCECTEHistologySBFTObscure gastrointestinal bleeding Hara,2Hara A.K. Leighton J.A. Sharma V.K. et al.Small bowel: preliminary comparison of capsule endoscopy with barium study and CT.Radiology. 2004; 230: 260-265Crossref PubMed Scopus (252) Google Scholar 200443Gold standardCT: 25% (86%)—5% (100%) Eliakim,60Eliakim R. Suissa A. Yassin K. et al.Wireless capsule video endoscopy compared to barium follow-through and computerised tomography in patients with suspected Crohn's disease: final report.Dig Liver Dis. 2004; 36: 519-522Abstract Full Text Full Text PDF PubMed Scopus (159) Google Scholar 20042089% (83%)—Gold standard57% (83%)Crohn's disease Dubcenco,28Dubcenco E. Jeejeebhoy K.N. Petroniene R. et al.Capsule endoscopy findings in patients with established and suspected small-bowel Crohn's disease: correlation with radiologic, endoscopic, and histologic findings.Gastrointest Endosc. 2005; 62: 538-544Abstract Full Text Full Text PDF PubMed Scopus (108) Google Scholar 20053990% (100%)bCalculated sensitivity and specificity comparing IC and SBFT with VCE.—Gold standard28% (100%) Solem,29Solem C.A. Loftus Jr, E.V. Fletcher J.G. et al.Small-bowel imaging in Crohn's disease: a prospective, blinded, 4-way comparison trial.Gastrointest Endosc. 2008; 68: 255-266Abstract Full Text Full Text PDF PubMed Scopus (291) Google Scholar 20084183% (53%)cSensitivity and specificity calculated compared with consensus diagnosis.82% (89%)74% (100%)65% (94%) Jensen,32Jensen M.D. Nathan T. Rafaelsen S.R. et al.Diagnostic accuracy of capsule endoscopy for small bowel Crohn's disease is superior to that of MR enterography or CT enterography.Clin Gastroenterol Hepatol. 2011; 9: 124-129Abstract Full Text Full Text PDF PubMed Scopus (185) Google Scholar 201193100% (91%)76% (85%), MRE 81% (86%)Gold standard—Celiac disease Rondonotti,38Rondonotti E. Spada C. Cave D. et al.Video capsule enteroscopy in the diagnosis of celiac disease: a multicenter study.Am J Gastroenterol. 2007; 102: 1624-1631Crossref PubMed Scopus (149) Google Scholar 20074387.5% (91%)—Gold standard— Hopper,39Hopper A.D. Sidhu R. Hurlstone D.P. et al.Capsule endoscopy: an alternative to duodenal biopsy for the recognition of villous atrophy in coeliac disease?.Dig Liver Dis. 2007; 39: 140-145Abstract Full Text Full Text PDF PubMed Scopus (85) Google Scholar 20072185% (100%)—Gold standard— Rokkas,40Rokkas T. Niv Y. The role of video capsule endoscopy in the diagnosis of celiac disease: a meta-analysis.Eur J Gastroenterol Hepatol. 2012; 24: 303-308Crossref PubMed Scopus (85) Google Scholar 201216689% (95%)—Gold standard—Nonresponsive celiac disease Atlas,42Atlas D.S. Rubio-Tapia A. Van Dyke C.T. et al.Capsule endoscopy in nonresponsive celiac disease.Gastrointest Endosc. 2011; 74: 1315-1322Abstract Full Text Full Text PDF PubMed Scopus (59) Google Scholar 20114256% (85%)—Gold standard—a Numbers shown as sensitivity (specificity) in table.b Calculated sensitivity and specificity comparing IC and SBFT with VCE.c Sensitivity and specificity calculated compared with consensus diagnosis. Open table in a new tab In a subsequent four-way crossover trial published in 2008, 41 patients with suspected or known Crohn's disease underwent testing with CTE (performed in all patients), IC (in 36 patients), SBFT (N = 38), and VCE (N = 28; 10 patients excluded because of partial small bowel obstructions, and 2 patients dropped out).29Solem C.A. Loftus Jr, E.V. Fletcher J.G. et al.Small-bowel imaging in Crohn's disease: a prospective, blinded, 4-way comparison trial.Gastrointest Endosc. 2008; 68: 255-266Abstract Full Text Full Text PDF PubMed Scopus (291) Google Scholar Active Crohn's disease was present in 51% of the cohort, and 42% were normal. Overall, VCE had a sensitivity of 83%, which was comparable with that of CTE for the diagnosis of small bowel Crohn's disease, but the specificity for VCE was 52%, which was lower compared with CTE, IC, and SBFT because of the presence of nonspecific VCE findings. In a meta-analysis comparing the yield of VCE with SBFT and IC for suspected or established Crohn's disease, the number needed to treat was 3 for the use of VCE compared with SBFT and number needed to treat = 7 comparing IC with VCE. Although the differences were highly statistically significant for patients with established Crohn's disease, use of VCE did not show a significant advantage compared with the other modalities for patients with suspected Crohn's disease.30Triester S.L. Leighton J.A. Leontiadis G.I. et al.A meta-analysis of the yield of capsule endoscopy compared to other diagnostic modalities in patients with non-stricturing small bowel Crohn's disease.Am J Gastroenterol. 2006; 101: 954-964Crossref PubMed Scopus (476) Google Scholar The authors questioned whether this latter result was due to a lack of adequate sample size because of the small number of patients with suspected Crohn's disease in these studies. A subsequent meta-analysis in 2010 was performed to determine whether the use of VCE was also the preferred modality for patients with suspected Crohn's disease by using a larger sample size.31Dionisio P.M. Gurudu S.R. Leighton J.A. et al.Capsule endoscopy has a significantly higher diagnostic yield in patients with suspected and established small-bowel Crohn's disease: a meta-analysis.Am J Gastroenterol. 2010; 105: 1240-1248Crossref PubMed Scopus (286) Google Scholar The authors performed an analysis of 12 trials that included more than 428 patients who had undergone testing with PE, VCE, SBFT, IC, CTE, or MRE. The results demonstrated that VCE yield for suspected Crohn's disease patients was superior to those of PE, SBFT, IC, and CTE. The differences between VCE and MRE were not