Colonoscopy GI Bleeding

Colonoscopy is a crucial diagnostic tool for identifying the source of gastrointestinal (GI) bleeding in the lower GI tract, specifically the colon and rectum. It is used both for diagnostic purposes and for therapeutic intervention when bleeding is identified.

Indications for Colonoscopy in GI Bleeding

Colonoscopy is typically performed in cases of lower GI bleeding where the bleeding source is suspected to be in the colon or rectum. Indications include:

Acute Lower GI Bleeding:

• Hematochezia (bright red blood per rectum) or maroon stools.
• Severe or ongoing rectal bleeding that cannot be controlled with conservative measures.

Chronic or Recurrent GI Bleeding:

• Occult blood loss detected via stool tests (e.g., positive fecal occult blood test or stool DNA test).
• Unexplained iron-deficiency anemia, suggesting chronic bleeding.

Abnormal Imaging Results:

• Positive findings from a barium enema, CT colonography, or abdominal imaging suggesting a potential source in the colon.

Surveillance in High-Risk Populations:

• Patients with a history of polyps, colorectal cancer, inflammatory bowel disease (IBD), or diverticular disease.

Causes of GI Bleeding Identified by Colonoscopy

Diverticular Disease:

• Diverticulosis: Small pouches or sacs in the colon wall that can bleed, especially in the sigmoid colon.
• Diverticulitis: Inflammation of diverticula can cause infection and bleeding.

Colorectal Polyps and Cancer:

• Benign Polyps: Can bleed, especially adenomatous polyps.
• Colorectal Cancer: Tumors can ulcerate or invade blood vessels, leading to bleeding.

Inflammatory Bowel Disease (IBD):

• Ulcerative Colitis: Chronic inflammation of the colon with bleeding as a prominent symptom.
• Crohn's Disease: Can cause ulcers, fistulas, and bleeding in the colon or other parts of the GI tract.

Angiodysplasia:

• Vascular malformations that cause slow, intermittent bleeding, usually in the cecum or right colon.

Hemorrhoids and Anal Fissures:

• Can cause bright red blood per rectum, especially with straining or during bowel movements.

Ischemic Colitis:

• Reduced blood flow to the colon, often affecting the left colon, resulting in bleeding and inflammation.

Infectious Colitis:

• Infections like Clostridium difficile or other pathogens can cause inflammation and bleeding in the colon.

Risks and Complications

Although colonoscopy is generally safe, there are potential risks, especially when performed for GI bleeding:

• Bleeding: From biopsies, polypectomies, or therapeutic interventions.
• Perforation: Rare but more likely if there is active inflammation or infection.
• Infection: While uncommon, infection can occur in the colon, particularly with certain therapeutic interventions.