Diverticular bleed

Pathophysiology: Intimal thickening and medial thinning of vasa recta as they course over dome of diverticulum → weakening of vascular wall → arterial rupture. Diverticula more common in left colon; but bleeding diverticula more often in right colon.

Clinical: older, ASA/NSAIDs, usually painless hematochezia ± abd cramping

Treatment: Usually stops spontaneously (~75%); ~20% recur. Can perform endoscopic hemostasis. Surgery (partial colectomy) last resort.