Diverticular bleeding
Diverticular bleeding is painless arterial hematochezia from rupture of a vasa recta at the neck or dome of a colonic diverticulum, the most common cause of severe acute lower gastrointestinal bleeding, and it stops spontaneously in about 75% of episodes. Diagnosis rests on hemodynamic triage followed by urgent colonoscopy or CT angiography to localize the source, and management combines resuscitation with a restrictive transfusion threshold, endoscopic hemostasis, and angiographic embolization or surgery for refractory bleeding.
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What this article covers
- Overview
Definition: diverticular bleeding is acute, painless hematochezia caused by rupture of a vasa recta, the small penetrating artery crossing the dome or neck of a colonic diverticulum.
- Epidemiology
Built on a common substrate: diverticulosis is present in roughly 80% of people 85 years and older, and about 15% of patients with diverticulosis develop a complication, chiefly bleeding or diverticulitis.
- Risk factors
Diverticulosis itself: the obligate substrate; bleeding cannot occur without an existing diverticulum.
- Pathophysiology
Diverticulum formation: chronic elevation of intraluminal colonic pressure combined with focal weakness of the colonic wall produces herniation of mucosa and submucosa through the muscularis at the…
- Clinical features
Sudden, painless hematochezia: the hallmark presentation is the abrupt passage of maroon or bright red blood per rectum without preceding or accompanying abdominal pain, which is the key feature…
- Differential diagnosis
Diverticulitis: left lower quadrant pain, fever, and leukocytosis from peridiverticular inflammation; rectal bleeding is uncommon, unlike the painless hemorrhage of diverticular bleeding (Diverticulitis).
- Diagnosis
Diverticular bleeding is confirmed by direct visualization of active bleeding, a nonbleeding visible vessel, or an adherent clot at a diverticulum on colonoscopy, or by extravasation from a…
- Management
Resuscitate first, in parallel with localization: two large-bore (minimum 18-gauge) peripheral IV catheters, IV crystalloid to restore hemodynamic stability, correction of coagulopathy, and…
- Complications
Hemorrhagic shock: occurs with brisk, ongoing bleeding before stabilization and source control are achieved.
- Prognosis
Favorable in the majority: about 75% of episodes stop spontaneously, and most patients recover fully with or without endoscopic intervention.
- Prevention
Avoid nonaspirin NSAIDs indefinitely after any episode of diverticular or angiodysplasia-related bleeding.
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Related articles
- Diverticulosis
Diverticulosis is the acquired presence of uninflamed mucosal and submucosal herniations through the colonic wall, overwhelmingly asymptomatic and usually found incidentally on colonoscopy or CT, that serves as the anatomic substrate for diverticulitis and diverticular bleeding rather than a disease in itself. Management of uncomplicated diverticulosis is a high-fiber diet with no restriction of nuts, seeds, or popcorn, plus routine age-based colorectal cancer screening.
- Diverticulitis
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- Acute lower gastrointestinal bleeding
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