A 45-year-old woman with a history of H. pylori infection (treated 2 years ago) presents with recurrent epigastric pain. Endoscopy shows an antral ulcer. A 38-year-old man with chronic aspirin use for secondary prevention of MI presents with acute epigastric pain. Endoscopy shows a duodenal ulcer. Which finding best distinguishes the location and pattern of these two ulcer types?

Explanation

## Location and Pattern: H. pylori vs. NSAID Peptic Ulcers ### Anatomical Discrimination **Key Point:** The **anatomical location and wall involvement** is a key discriminating feature. H. pylori ulcers classically occur on the **lesser curve of the stomach** (antral region), while NSAID ulcers preferentially affect the **anterior wall of the duodenum**, particularly near the gastroduodenal artery. ### Comparative Anatomy and Location | Feature | H. pylori Ulcer | NSAID Ulcer | |---------|-----------------|-------------| | **Primary location** | Antrum (lesser curve) | Duodenum (anterior wall) | | **Stomach involvement** | Common (antral > fundal) | Less common | | **Duodenal involvement** | Can occur | Predominant (anterior > posterior) | | **Multiple ulcers** | Possible but less common | Possible but less common | | **Posterior duodenal ulcers** | Rare | More common (erosion into gastroduodenal artery) | | **Perforation site** | Anterior gastric wall (less bleeding) | Anterior duodenum (less perforation) | ### Clinical Significance of Location **Clinical Pearl:** The location of the ulcer has prognostic implications. Anterior duodenal ulcers (typical of NSAID use) are prone to **perforation** with peritonitis, while posterior duodenal ulcers are prone to **hemorrhage** from erosion into the gastroduodenal artery. H. pylori antral ulcers are less likely to erode into major vessels. **High-Yield:** When you see an endoscopy report of an **antral ulcer on the lesser curve**, think H. pylori. When you see an **anterior duodenal ulcer**, think NSAIDs. This anatomical pattern is one of the most reliable clinical discriminators and is frequently tested in NEET PG. ### Mnemonic **H. pylori = Antral, NSAID = Anterior Duodenum (AND)** — H. pylori affects the antrum (lesser curve); NSAIDs affect the anterior duodenum.