# Peptic Ulcer

> Peptic ulcer pathology for NEET-PG Pathology: Helicobacter pylori and NSAID causes, gastric versus duodenal sites, complications and Zollinger-Ellison.

- Canonical URL: https://prepelephant.com/topics/neet-pg/pathology/peptic-ulcer-pathology
- Exam / course: NEET-PG · Subject: Pathology
- Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team
- First published: 2026-10-02
- Last updated: 2026-10-02
- How to cite: "Peptic Ulcer", PrepElephant, https://prepelephant.com/topics/neet-pg/pathology/peptic-ulcer-pathology

## Direct answer

A peptic ulcer is a full-thickness breach of the mucosa into the submucosa or deeper, produced by acid-peptic digestion where mucosal defences have failed — most often from Helicobacter pylori infection or non-steroidal anti-inflammatory drugs. Duodenal ulcers, the commoner type in younger men, cluster in the first part of the duodenum and are almost never malignant, whereas gastric ulcers favour the lesser curvature of the antrum and must always be biopsied. The crater histologically shows necrotic fibrinous debris over granulation tissue and scar — the four-layered look of a chronic ulcer.

## What you must remember

- **Causes:** Helicobacter pylori underlies the great majority of duodenal ulcers and most gastric ulcers; NSAIDs follow, then Zollinger-Ellison syndrome; smoking and stress aggravate healing.
- **Duodenal ulcer:** posterior wall of the first part (bulb); pain classically relieved by food and waking the patient at night; posterior penetration erodes the gastroduodenal artery — the commonest cause of a major bleed — while anterior wall perforation dumps gastric contents into the peritoneum.
- **Gastric ulcer:** lesser curve of the antrum or junction of antrum-body mucosa; pain worse after meals with weight loss; up to a minority are malignant, so every gastric ulcer needs biopsy and follow-up endoscopy.
- **Gross and microscopic morphology:** sharply punched-out crater with straight walls and clean base, unlike the heaped, everted margins of a carcinoma; layers of superficial necroinflammatory exudate, granulation tissue and fibrous scar.
- **Complications:** haemorrhage (haematemesis and melaena, most frequent), perforation with peritonitis, penetration into pancreas or liver, gastric outlet obstruction from oedema and scarring, and malignant change — gastric ulcers only.
- **Zollinger-Ellison syndrome:** gastrin-secreting tumour (duodenum more than pancreas), about a quarter in MEN1 setting, causing multiple, distal and refractory ulcers with diarrhoea; secretin provocation raises gastrin paradoxically.
- **Treatment:** proton-pump inhibitor plus H. pylori eradication (triple or quadruple therapy per current guidance) and NSAID avoidance; surgery reserved for complications.

## Common confusion

Gastric versus duodenal ulcer decides the answer in nearly every stem: food-aggravated pain, lesser curve and malignant potential versus food-relieved pain, bulb location and benign course. A benign crater is sharply demarcated with flat margins, while carcinoma shows everted, rolled margins — gross and radiological signs examiners love. Bleeding source is positional: posterior bulb → gastroduodenal artery; gastric ulcer and varices add their own contexts. Remember duodenal ulcers never turn malignant.

## Exam-focused takeaway

Questions deliver a young man with night-time pain eased by milk (duodenal ulcer), an elderly NSAID user with melaena (gastric ulcer bleed), or sudden catastrophic abdominal pain with free air (perforation). One-liners test the four histological zones, the artery eroded in posterior perforation, and the paradoxical secretin response of gastrinoma. Close the loop with H. pylori — cause, diagnostic test and eradication regimen.

## Frequently asked questions

### What is the most common cause of peptic ulcer disease?

Helicobacter pylori infection, compounded by non-steroidal anti-inflammatory drugs through dual mucosal-defence failure.

### Which artery bleeds in a posterior duodenal ulcer?

The gastroduodenal artery, eroded as the ulcer penetrates posteriorly from the first part of the duodenum.

### Why are gastric ulcers biopsied?

Because a minority prove to be carcinoma or harbour dysplasia, unlike duodenal ulcers, which are essentially never malignant.

### What is Zollinger-Ellison syndrome?

A gastrinoma (usually duodenal or pancreatic, often with MEN1) driving acid hypersecretion, multiple refractory ulcers and diarrhoea.

### What are the four histological zones of a chronic ulcer?

Necrotic fibrinous debris, a zone of active inflammation, granulation tissue and, deepest, fibrous scar tissue.