Peptic Ulcer Disease

Definition

Peptic ulcer disease (PUD) refers to mucosal erosions equal to or greater than 5 mm in the stomach or duodenum, caused by an imbalance between mucosal protective mechanisms and aggressive factors such as acid and pepsin.

Epidemiology

• Global prevalence: ~5–10% lifetime risk
• Incidence declining due to H. pylori eradication and reduced NSAID use
• Peak incidence: 40–60 years for duodenal ulcers, 60–70 years for gastric ulcers
• Male predominance in duodenal ulcers; gastric ulcers equal gender distribution
• Complications: bleeding (most common), perforation, gastric outlet obstruction

Etiology

• Helicobacter pylori infection (most common cause)
• Nonsteroidal anti-inflammatory drugs (NSAIDs) and aspirin
• Stress-related mucosal damage (critical illness, burns, trauma)
• Zollinger-Ellison syndrome (gastrinoma leading to excess acid)
• Smoking, alcohol consumption, and chronic illness as risk modifiers
• Genetic predisposition (family history of PUD)

Pathophysiology

• Disruption of mucosal protective factors: mucus, bicarbonate, prostaglandins, epithelial regeneration, mucosal blood flow
• Excess gastric acid and pepsin secretion overwhelms defense mechanisms
• H. pylori infection induces chronic gastritis, increasing acid exposure and reducing mucosal protection
• NSAIDs inhibit prostaglandin synthesis, impairing mucosal defense and healing
• Chronic inflammation can lead to ulceration, scarring, and complications
• Ulcer healing may be incomplete, leading to recurrence if underlying cause persists