Most Common Sources of GI Bleeding in America
The most common sources of gastrointestinal bleeding in America differ by anatomic location: peptic ulcer disease (gastric and duodenal ulcers) is the leading cause of upper GI bleeding, while diverticulosis is the most common cause of lower GI bleeding. 1, 2
Upper GI Bleeding Sources (Proximal to Ligament of Treitz)
Most Common Causes
Peptic ulcer disease accounts for the majority of nonvariceal upper GI bleeding, with gastric ulcers representing 32% and duodenal ulcers 28% of cases in large prospective series. 3 This is primarily related to Helicobacter pylori infection and NSAID use. 1, 2, 4
Esophageal varices represent 9% of upper GI bleeding cases, occurring predominantly in patients with cirrhosis and portal hypertension. 2, 3
Gastric erosions and stress-related mucosal disease are particularly prevalent in critically ill patients with risk factors including mechanical ventilation, coagulopathy, and renal failure. 2
Mallory-Weiss tears account for approximately 6% of cases, resulting from forceful vomiting or retching. 2, 3
Esophagitis and duodenitis represent additional inflammatory causes of upper GI bleeding. 2
Less Common but Important Causes
Dieulafoy lesions account for 1-2% of acute upper GI bleeding, consisting of tortuous submucosal arteries that penetrate the gastric mucosa, typically at the posterior gastric wall. 2
Angiodysplasia, vascular malformations, and neoplasms (including gastric cancer) represent additional etiologies. 2
Hemosuccus pancreaticus is responsible for approximately 1 in 500 cases of upper GI bleeding, making it the most common pancreatic cause. 5, 2
Hemobilia and aortoenteric fistula are rare but potentially catastrophic causes. 1, 2
Lower GI Bleeding Sources (Distal to Ligament of Treitz)
Most Common Causes
Diverticulosis is the leading cause of lower GI bleeding, accounting for 30-41% of cases across multiple studies. 1 The prevalence increases significantly with age, explaining the 200-fold increase in incidence from age 20 to 80 years. 1
Colitis and ulcers (including inflammatory bowel disease, infectious colitis, radiation colitis, and ischemic colitis) represent 12-21% of cases. 1
Anorectal sources (hemorrhoids, anal fissures, rectal ulcers) account for 5-14% of cases. 1
Cancer and polyps represent 6-14% of lower GI bleeding, with higher percentages in some series. 1
Angiodysplasia accounts for 3-40% of cases, with significant variation across studies, and like diverticulosis, increases in prevalence with age. 1
Critical Clinical Context
Approximately 10-15% of patients presenting with acute severe hematochezia actually have an upper GI source identified on upper endoscopy, emphasizing the importance of considering upper sources even with bright red blood per rectum. 1
Small bowel sources account for only 0.7-9% of cases presenting as severe hematochezia. 1
Upper GI bleeding has an incidence of 61-78 cases per 100,000 persons, which is 4-5 times higher than lower GI bleeding (20.5-27 cases per 100,000). 1
Mortality rates are 2-10% for upper GI bleeding and 2-4% for lower GI bleeding, though 75-85% of cases stop spontaneously. 1, 2