Management of Hematochezia with Inconclusive Colonoscopy and Bleeding Around Ileocecal Valve
For a patient with hematochezia where colonoscopy cannot determine the bleeding focus but reveals bleeding around the ileocecal valve and old blood from the descending colon, the first step should be to repeat colonoscopy. 1
Diagnostic Algorithm for Obscure Lower GI Bleeding
First-Line Approach
- Repeat colonoscopy is recommended as the first step when initial colonoscopy is inconclusive but suggests bleeding around the ileocecal valve 1
- A thorough bowel preparation is essential to improve visualization, as poor preparation may have led to incomplete evaluation of the colonic mucosa in the first examination 1
- Special attention should be paid to the ileocecal valve area, with careful intubation of the terminal ileum 2, 3
Rationale for Repeat Colonoscopy
- The diagnostic accuracy of colonoscopy ranges from 72-86% in patients with lower gastrointestinal bleeding 1
- Terminal ileoscopy can provide valuable information in patients with hematochezia and should be attempted when the source of bleeding is not identified in the colon 2
- Findings of bleeding around the ileocecal valve suggest a possible small bowel source that may be accessible via terminal ileoscopy 2, 3
Alternative Diagnostic Steps if Repeat Colonoscopy is Inconclusive
Nuclear Scintigraphy
- If repeat colonoscopy fails to identify the source, radionuclide imaging with [99Tcm] pertechnetate-labeled red blood cells should be considered 1
- Scintigraphy can detect active bleeding at rates of 0.1-0.5 mL/min and is more sensitive than angiography 1
- Early scans (<4 hours after baseline) are more helpful in localizing the bleeding site than delayed scans 1
Angiography
- Angiography should be performed only after positive scintigraphy or in patients with hemodynamic instability and severe unremitting bleeding 1
- Angiography requires a bleeding rate of at least 1 mL/min for accurate detection of extravasation 1
- A positive red blood cell scan should necessitate urgent angiography within 1 hour of positive scintigraphy 1
Special Considerations
Terminal Ileum Evaluation
- Retrograde terminal ileoscopy gives limited but valuable information in patients with hematochezia and should be attempted during repeat colonoscopy 2
- In one study of hematochezia patients with normal colonoscopy, terminal ileoscopy revealed pathology including ileal ulcers, nodularity, Dieulafoy's lesion, and angiomatous malformation 2
- The technique for intubation of the ileocecal valve should be methodical to facilitate successful ileoscopy 3
Potential Findings
- Angiodysplasia is a common cause of obscure GI bleeding, accounting for up to 80% of cases 1
- Small bowel tumors are the most common cause of obscure bleeding in patients younger than 50 years 1
- Colonic angiodysplasia are most common in the cecum and proximal ascending colon (54%), followed by the sigmoid colon (18%) and rectum (14%) 1
Precautions During Colonoscopy
- Assess bleeding risk prior to the procedure with correction of coagulopathy if present 4
- Check vital signs, determine hemoglobin and hematocrit, and assess coagulation parameters 4
- Consider blood typing and cross-matching in case transfusion becomes necessary 4
- Maintain hemoglobin levels >7 g/dL during any procedure 4
Common Pitfalls to Avoid
- Inadequate bowel preparation leading to poor visualization of the mucosa 1
- Use of narcotic medication for sedation may decrease the sensitivity of colonoscopy for detecting angiodysplasia by transiently decreasing mucosal blood flow 1
- Failure to examine the terminal ileum when lower GI bleeding source is not identified in the colon 2
- Premature resort to more invasive procedures before optimizing endoscopic evaluation 1