Finding Sources of Obscure Lower GI Bleeding

1. به نام خدا

2. Finding Sources of Obscure Lower GI Bleeding Dr.P.Fallah Abed

5. Causes of Hematochezia • COLONIC BLEEDING (95%) SMALL BOWEL BLEEDING (5%) • Diverticular disease 30-40 Angiodysplasias • Ischemia 5-10 Erosions or ulcers (K, NSAIDs) • Anorectal disease 5-15 Crohn's disease • Neoplasia 5-10 Radiation • Infectious colitis 3-8 Meckel's diverticulum • Postpolypectomy 3-7 Neoplasia • IBD 3-4 Aortoenteric fistula • Angiodysplasia 3 • Radiation colitis/proctitis1-3 • Other 1-5 • Unknown 10-25

6. Causes of Hematochezia • Diverticulosis • Bleeding occurs in only 3-5% • Left-sided source more common when diagnosed by colonoscopy • Right-sided source more common when diagnosed by angiography • Angiodysplasia • Most common in cecum and ascending colon • When in the small bowel, presents as iron deficiency anemia and rarely as hematochezia

7. Causes of Hematochezia • Hemorrhoids • Ischemic colitis • Neoplasms • NSAID-induced injury in terminal ileum and proximal colon • IBD • 10-15% of hematochezia caused by upper GI bleed

8. History • NSAIDs & ASA strongly associated with lower GI bleeding just as with upper GI bleeding • Stercoral ulcers caused by severe constipation • Recent polypectomy • Hypovolemia preceding bleed suggests ischemic colitis

9. Going Hunting

10. Going Hunting • Bleeding source not found in 25% • KUB to look for perforation or obstruction • NG aspirate • Colonoscopy • No agreement over whether prep is needed because of increased risk of perforation with unpreped colon • Radionuclide imaging • Can detect slow bleeds at 0.1-0.5ml/min • More sensitive but less specific than angiography

11. Going Hunting • Angiography • Requires bleeding of at least 1ml/min • Very specific but not very sensitive • May cause bowel infarction, renal failure • Small bowel evaluation • Push enteroscopy can allow evaluation of the first 60cm of jejunum • Video capsule to evaluate the remainder • Meckel scan

12. Strategy with Lower GI bleeding • If persistently unstable and major bleeding, proceed to surgery • If colonic source, subtotal colectomy with ileorectal anastomosis • If small bowel source, resection • If no identified source, intraoperative enteroscopy followed by resection • If stable and major bleeding • Tagged red cell scan • If positive, follow with angiography • If negative, capsule endoscopy, enteroclysis, enteroscopy

13. Strategy with Lower GI bleeding • If stable and minor bleeding • Colonoscopy • If negative, capsule endoscopy, enteroclysis, enteroscopy • If all studies negative • Colonoscopy if rebleeding

15. Don’t Forget • In addition to basic labs (CBC, Chemistries, Coags), obtaining type and cross • Two large bore peripheral IV’s • Rectal exam as up to 40% of rectal cancers can be detected this way

18. Case Presentation • A 41 year old AA male was admitted to the hospital after an acute episode of bleeding per rectum • Admission hemoglobin = 6.2 g/dl • The patient had a recent stay at a local private hospital for investigation of bleeding per rectum within the last 3 months and upper GI endoscopy, colonoscopy, small bowel contrast study were normal • Following his last hospitalization, he was discharged on iron supplements

19. Case Presentation • The gastrointestinal ROS: otherwise negative. He had had no abdominal pain, weight loss, or change in bowel function. Strong family history of PVD/MI • PMH: • CHF EF ~ 30% on last echo • HTN • DM • PVD • RA/GOUT • Hx. AAA

20. Case presentation • Meds: • Metoprolol • ASA • Plavix • Insulin • Allopurinol • Methotrexate 10 mg weekly • Celebrex

22. Case presentation • Routine laboratory: all normal except for initial hemoglobin level of 6.2 • Coagulation, liver chemistries, blood urea nitrogen, and creatinine levels were normal • Nasogastric aspirate produced bile-stained gastric contents but no blood • Results of proctoscopy performed in the emergency department showed red blood but no source of bleeding • The patient was admitted to the surgical intensive care unit (ICU)

23. Case presentation • What is our DDX? • What would you do for this patient?

24. Case presentation • AVM • Camerons lesion • Dieulafoy • Gastric or duodenal varices • Neoplasm • Aortoenteric fistula • Hemobilia • Hemosuccus pancreaticus • Meckel’s • IBD • Celiac sprue • NSAID enteropathy

26. Obscure GI BleedingDefinition • Bleeding of unknown origin that persists or recurs after negative colonoscopy and negative upper endoscopy • Recurrent or persistent bleeding • FOBT positive • IDA • Visible bleeding • Melena, hematemesis, hematochezia, coffee grounds

28. Obscure GI BleedingFrequency • 10% - 20% of GI bleeding without identifiable etiology • 5% GI bleeding recurrent without identifiable etiology • Majority have small bowel source

29. Obscure GI BleedingSmall BowelCauses Grouped by Age • Patient’s < 25 years old • Meckel’s Diverticula • Patient’s between 30 – 50 years old • Tumors • Patient’s > 50 years old • Vascular ectasias

30. Small Bowel BleedingCauses By Etiology • Vascular Lesions • Neoplasms • Inflammatory Lesions • Other

32. Small Bowel BleedingVascular Lesions • Angioectasias • Telangiectasias • Hereditary hemorrhagic telangiectasia • Osler-Weber-Rendu Syndrome • CREST Syndrome • Calcinosis, Reynaud’s, Esophageal dysmotility Sclerodactyl, Telangiectasia • Other • Dieulafoy’s lesion • Aortoenteric fistula • Small bowel varices

33. Small Bowel BleedingAngiodysplasia • Dilated tortuous blood vessels with thin walls lined by endothelium with little or no smooth muscle • Most common small bowel bleeding in the elderly (> 50 years old) • May be associated with aging associated degeneration of vascular integrity

34. Small Bowel BleedingTumors • Second most common cause of bleeding • One out of ten patients with obscure bleeding will have a small bowel tumor • Most common cause in persons age 30 – 50 years of age • Malignant and Benign • Adenocarcinoma, carcinoid, lymphoma, leiomyosarcoma, • Leiomyoma, polyps (Peutz-Jeghers, familial polyposis), GIST • Metastatic • Melanoma, breast, renal-cell, kaposi’s sarcoma, colon, ovarian

35. Causes of Small Bowel BleedingDiverticula • Small bowel diverticula • At the site of perforating blood vessels • Meckel’s diverticulum • Remnant of vitelline duct in distal ileum • Most common cause of small bowel bleeding in patients under the age of 25 years old • Ectopic gastric tissue causes ulceration • Intussusception • Inverted Meckel’s, angioectasias, submucosal tumors

36. Small Bowel BleedingInflammatory Lesions • Crohn’s Disease • Isolated ulcers • Idiopathic ulcers • Nonsteroidal antiinflammatory drugs • Ischemic • Other • Vasculitis, Zollinger-Ellison syndrome, Celiac disease

37. Small Bowel BleedingRare Causes • Hemobilia • Neoplasm, vascular aneurysm, liver abscess, trauma, liver biopsy • Hemosuccus pancreaticus • Pancreatic pseudocysts, pancreatitis, neoplasms • Erosion into a vessel with communication with PD • Infections • Cytomegalovirus, histoplasmosis, Tb

39. Small Bowel Bleeding Diagnosis • UGI SBFT • Enteroclysis • Push enteroscopy • Double balloon enteroscopy • Intraoperative enteroscopy • CT scan  ionizing radiation…. • CT enteroclysis • MRI  no ionizing radiation • Video capsule endoscopy

40. Obscure BleedingSBFT and Enteroclysis • SBFT • 0-5.6% diagnostic yield • Used for exclusion of structural lesion or fistula • Enteroclysis • Superior to SBFT • Double contrast, Tube into proximal small bowel • Inject barium, methylcellulose, air • Performed with CT and MRI • Only 10-21% diagnostic yield • Use if capsule endoscopy or enteroscopy unavailable

43. Obscure GI BleedingAngiography • Severe bleeding • Bleeding rate of 0.5 mL/min • Positive in 27-77% of acute LGI bleeding • Positive in 61-72% if, • Pt actively bleeding requiring transfusion • Hemodynamic compromise • TRBC scan shows an immediate blush • Administer anticoagulants, vasodilators, clot-lysing agents to precipitate bleeding • Increased diagnostic yield from 32 to 65% • 17% complication rate including excessive bleeding

45. bscure BleedingEnteroscopy • Pass scope beyond the ligament of Treitz • Adult or pediatric colonoscope, SB enteroscope • Diagnostic yield : 40-50% • Angiodysplasia in 80% • Advantage over capsule endoscopy • Sample tissue • Endoscopic therapy

46. Obscure GI BleedingExploratory Laparotomy • Seldom without intraoperative enteroscopy • 65% of 37 pt’s had lesion identified by palpation or transillumination

48. Wireless Capsule Endoscopy Patient Experience • Sensors placed and attached to data recorder • Easily ingested, painless procedure • Progresses naturally through the GI tract via peristalsis • Transmits images to data recorder

49. PillCam SB Patient Experience • Liquid diet from lunch the day before • Movie Prep the night before • 12 hour fast the night before • Capsule ingested in the morning • Reglan or erythromycin for inpatients • Liquid diet after 2 hours • Light meal 4 hours after ingestion • Disconnect after 8 hours