Angiodysplasia of the colon
Angiodysplasia of the colon is an acquired vascular ectasia, most often in the cecum and ascending colon of older adults, that causes painless intermittent or chronic hematochezia and iron deficiency anemia. Colonoscopy establishes the diagnosis and delivers first-line treatment with endoscopic thermal ablation such as argon plasma coagulation.
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What this article covers
- Overview
Angiodysplasia of the colon, also called angiectasia or an arteriovenous malformation, is an acquired lesion of ectatic, dilated, thin-walled blood vessels of the mucosa and submucosa, most often clustered in the cecum and ascending colon.
- Epidemiology
Age: Clinical bleeding concentrates in patients older than 60 years; angiodysplasia is the most common identified cause of small-bowel bleeding in this age group.
- Risk factors
Advanced age: Chronic colonic wall stress accumulates over decades, so risk rises past age 60.
- Pathophysiology
The lesion is an aberrant, dilated submucosal blood vessel with an abnormally thin wall; the bleed follows its erosion into the bowel lumen.
- Clinical features
Occult presentation: Chronic, low-volume blood loss detected only as iron deficiency anemia, fatigue, weakness, or exertional dyspnea, with no blood noted by the patient.
- Differential diagnosis
Diverticular bleeding: Also painless hematochezia in an older adult, but abrupt and higher volume; colonoscopy shows a diverticulum with a visible vessel or clot, not a vascular lesion.
- Diagnosis
First, what establishes the diagnosis: Direct visualization of a flat, red, fernlike vascular lesion at colonoscopy, or at video capsule or push enteroscopy for a small-bowel lesion; no blood test or imaging finding confirms it alone.
- Management
Immediate stabilization for active or hemodynamically significant bleeding: Secure intravenous access, give crystalloid, and transfuse packed red blood cells once hemoglobin falls below 7 g/dL in a…
- Complications
Recurrent or refractory bleeding: The rebleeding rate after angiodysplasia-related LGIB is 37% to 64%, higher than after diverticular bleeding.
- Prognosis
Most bleeding episodes stop spontaneously and respond to endoscopic therapy, but angiodysplasia is chronic and relapsing rather than cured by one treatment; new lesions can develop at other sites over years.
- Prevention
Avoid nonaspirin NSAIDs after any diverticular or angiodysplasia-related bleeding episode, a modifiable driver of recurrence.
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