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OBSCURE GI BLEED. Talat Bessissow , MC CM, FRCPC Assistant Professor, Department of Medicine Division of Gastroenterology McGill University Health Center. Definition. Definition = GI bleeding of uncertain etiology after EGD, C-scope, and small bowel radiography
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OBSCURE GI BLEED TalatBessissow, MC CM, FRCPC Assistant Professor, Department of Medicine Division of Gastroenterology McGill University Health Center
Definition • Definition = GI bleeding of uncertain etiology after EGD, C-scope, and small bowel radiography • Overt OGIB = hematochezia, melena, hematemesis or CG emesis • Occult OGIB = FOB + in abscence of visible blood, Iron deficiency Anemia
Fecal occult blood testing • Guaiac-based tests: The pseudoperoxidase activity of hemoglobin turns the guaiac compound blue in the presence of hydrogen peroxide
Epidemiology • 300,000 pts hospitalized/yr in US ... 5% of these will have normal EGD and C-scopes • Median time for diagnosis is 2 years • Average cost $33,630 per patient • Average 7.3 tests per patient • Paradigm shift since introduction of VCE and DBE
Etiology of Obscure GI Bleeding • 5% of patients presenting with GI hemorrhage have no source found by upper endoscopy and colonoscopy. • Of these, 75% are 2ndry to small bowel lesions • Of these, 30-60% angiectasias Am J Surg 1992;163:90–92 Br Med J (Clin Res Ed)1984;288:1663–1665.
Etiology • 40% of OGIB - due to angiectasias (AVMs) • Angiectasias : ectatic blood vessels made of thin wall with or without endothelial lining • Natural history of angiectasias is not well known • Only 10% of all patients with angioectasia will eventually bleed • Once a lesion has bled up to 50% will not rebleed --- predictors of rebleeding: multiple bleeding episodes, transfusion requirement • Bleeding angiectasias are associated with abnormal von Willebrand’s factor (vWF)
AVM • Conditions/diseases associated with angiodysplastic lesions: • Elderly • CRF • Aortic valve disease (Heyde’s syndrome) • Cirrhosis • Collagen vascular disease
What is Heyde’s syndrome ? • Heyde’s syndrome: Bleeding from angiectasias in patients with AS. • Increased consumption of high-molecular-weight multimers of VWF due to shear stress of the abnormal valve which corrects after aortic valve replacement with decreased severity of bleeding Transfus Med Rev 2003;17:272–286.; Abdom Imaging (2009) 34:311–319
Small Bowel Bleeding • Etiology depends on the age of the patient • Young: small intestinal tumors, Meckel’s diverticulum, Dieulafoy lesion, Crohn’s disease • Older: (>40) vascular lesions, NSAID-induced SB disease • Uncommon: hemobilia, hemosuccus pancreaticus, aortoenteric fistula
History and Physical Examination • The nature of the exact presenting symptom is important in deciding a practical, efficient, and cost-effective evaluation plan • Hematemesis indicate upper GI bleed • Melena can be anywhere from the nose to the right colon • Hematochezia can be a lower GI bleed or a fast upper GI bleed • History of medications (mainly OTC) • Family history • Skin signs
Investigation options • Repeat G & C • CTE • Capsule endoscopy • Enteroscopy - push or SBE/DBE • Angiography • Tagged RBC scan
Common lesions that are overlooked • EGD: Cameron’s erosions, fundic varices, PUD, angioectasias, Dieulafoy lesion, GAVE • C-scope: angioectasias, neoplasms
Investigation • Repeat standard endoscopy, especially if anemia and overt GI bleeding: • Overlooked lesions: fundus • high lesser curvature antrum C loop of duodenum, posterior wall of duodenal bulb • Random SB Bx can be + for celiac disease in up to 12% • The yield of repeat colonoscopy is 6%, yield of repeat EGD is 29% (ASGE) Am J Gastroenterol 1996;91:2099–2102
Investigation • Consider side-viewing scope if pancreatobiliary pathology is suspected • Small bowel series/SBFT: • When compared with capsule endoscopy • diagnostic yield 8% vs 67% • clinically significant finding 6% vs 42% (NNT 3) • Used if SB obstruction is suspected Gastroenterology 2002;123:999–1005
Investigation • CT Enterography: • Thin sections and large volumes of enteric contrast material to better display the small bowel lumen and wall. • Neutral enteric contrast + IV contrast • 1.5 – 2 L of milk, PEG electrolytes or low-concentration barium
Investigation • CT Enterography: • Advantages: displays entire wall thickness examination of deep ileal loops mesentery & perienteric fat no need for NGT
Investigation • Technetium-99m–labeled RBC scan: Limited value Blood loss of 0.1-0.4 ml/min (2U PRBCs /d) Poor localization of SB bleeding - not enough to direct operative therapy • Angiography: Useful in massive bleeding (>0.5ml/min) Diagnostic & therapeutic Nucl Med Commun 2002;23:591–594
Investigation • Endoscopic imaging: • Intraoperativeenteroscopy; Terminal ileum can be reached in 90% of cases • diagnostic yield 58-88% • mortality up to 17%
Investigations • Push enteroscopy: • Length 220-250 cm • usually limited to 150 cm • diagnostic yield up to 70% • angioectasias in up to 60% • some suggest push enteroscopy over repeat EGD as second look
Capsule endoscopy • Size 11x26 mm • Obtains images and transmits the data via radiofrequency to a recording device • The capsule is disposable • Examination takes at least 8 hours (57,600 images) • Reading 60 – 120 minutes • SB obstruction is a contraindication
Capsule endoscopy • Capsule endoscopy: yield 63% vs 23% for push enteroscopy Sensitivity 89 - 95% Specificity 75 – 95% +ve predictive value 97% -ve predictive value 86%
Lin, GIE 2008 • Rastogi et al. GIE 2004 • Pennazio et al. Gastroenterol 2004 • Apostolopoulos et al. Endoscopy 2006 • Estevez et al. Eur J Gastro Hep 2006 • Delvaux et al. Endoscopy 2004
Superior yield to other diagnostic modalities in both active and inactive obscure GI bleeds • * Marmo, APT 2005, Triester, AJG 2005, Saperas AJG 2007
Double Balloon Enteroscopy • Double Balloon Enteroscopy (DBE) • 1stdescribed in 2001 • 200-cm enteroscope • 140-cm overtube
Double Balloon Enteroscopy (DBE) • Antegradeapproach: mean distance 240 +/- 100 cm mean time 72.5 +/- 23 min • Retrograde approach: mean distance 140 +/- 90 cm mean time 75 +/- 28 min
Complications • Perforation – 0.3-1.1% • Bleeding (post-polypectomy) – 1.4-1.9% • Pancreatitis – 0.2-0.3% Melsink Endoscopy 2007, Gerson ACG 2008
Single Balloon Enteroscopy • Much more recent • Simpler to set up, works with existing Olympus equipment • Same specifications as DBE without the second balloon on the endoscope Hartmann, Endoscopy 2007
Single Balloon Enteroscopy Kawamura GIE 2008
SBE versus DBE • Efthymiou, abstract 2010 • RCT involving 79 patients recruited for mainly OvGIB/ObGIB • About half had SBE • Depth of insertion retrograde was identical (100 cm) • Depth of insertion orally favoured DBE (250 versus 205 cm but not significant) • Therapeutic yield was 54% DBE, 37% SBE (not significant) • Targetted biopsies or application of cautery or argon plasma
Pennazio et al. Endoscopy 2005 & AGA Technical Insitute. Gastroenterol 2007