Etiology

The two major contributing factors to the development of PUD are gastrointestinal infection with H. pylori and nonsteroidal anti-inflammatory drug (NSAID) use. Both factors contribute to the development of PUD and interact with other risk factors to promote ulcer formation.

• Helicobacter pylori infection

  • Associated with 40–70% of duodenal ulcers and 25–50% of gastric ulcers

  • The rate of H. pylori infection (and, therefore, the development of PUD) is decreasing.

• Chronic NSAID use

  • Associated with a fourfold risk of developing PUD

  • Increases the risk for complications of PUD

H. pylori infection or NSAID use alone do not typically cause ulcer formation. There are often additional risk factors present, such as the following, that increase the probability of developing an ulcer:

• Shared risk factors for PUD, GERD and gastritis (i.e., smoking, heavy alcohol use, glucocorticoids, caffeine)

• Diet

• Psychological factors (e.g., anxiety, stress, PTSD)

• Genetic factors

• Acid hypersecretory states

  • Zollinger-Ellison syndrome (gastrinoma)

  • Systemic mastocytosis

  • Hyperparathyroidism

• Non-NSAID medications

  • Acetaminophen

  • Bisphosphonates

  • Sirolimus

  • Mycophenolate

  • SSRIs

  • Chemotherapeutics (e.g., 5-FU)

• Infections

  • CMV

  • HSV-1

  • EBV

  • Helicobacter heilmannii

• Others

  • Radiation

  • Illicit drug use (e.g., cocaine, methamphetamine)

  • Systemic inflammatory diseases (e.g., Crohn disease, sarcoidosis)

  • Mechanical (e.g., foreign body, GI tract obstruction, postsurgical anatomy)