Peptic ulceration - H. pylori Flashcards
What is meant by the term ‘peptic ulcer’?
ulcer in the lower oesophagus, stomach or duodenum, in the jejunum after surgical anastomosis to the stomach or, rarely, ileum adjacent to Meckel’s diverticulum
What are 5 possible locations of peptic ulcers?
- Lower oesophagus
- Stomach
- Duodenum
- Jejunum after surgical anastomosis to stomach
- Ileum adjacent to Meckel’s diverticulum
What is the nature of peptic ulcers in the stomach or duodenum?
acute or chronic
Structurally, what is the difference between acute and chronic peptic ulcers?
both penetrate muscularis mucosae, but acute ulcer shows no evidence of fibrosis
How does an erosion differ structurall from a peptic ulcer?
erosions do not penetrate the muscularis mucosae
Why is the prevalence of peptic ulcer decreasing in many Western communities?
widespread use of H. pylori eradication therapy
Where are 90% of chronic gastric ulcers situated?
lesser curve within the antrum or at the junctino between body and antral mucosa
Where do chronic duodenal ulcers usually occur?
first part of duodenum; 50% on anterior wall
In what proportion of patients is there more than one peptic ulcer?
10-15% of patients
What proportion of a) duodenal ulcer and b) gastric ulcers are associated with H. pylori?
a) 90% b) 70%
What is responsible for the remaining 30% of gastric ulcers not accounted for by H. pylori?
NSAIDs
How is H. pylori spread?
acquired in childhood by person-to-person contact
What type of bacteria is H. pylori?
gram-negative and spiral, multiple flagella at one end
What type of mucosa does H. pylori colonise?
gastric type epithelium; only found in duodenum in association with patches of gastric metaplasia
How does H. pylori cause ulcers?
provokes local inflammatory response in the underlying epithelium, based on expression of genes cagA and vacA. CagA product injected into epithelial cells, interacting with cell-signalling pathways involved in replication and apoptosis
Whta are the 5 stages leading to duodenal ulceration?
- Depletion of antral D-cell somatostatin
- Increased gastrin release from G cell
- Increased acid secretion
- Increased acid load in duodenum leads to gastric metaplasia
- Further inflammation and eventual ulceration
What are 2 key environmental factors which contribute to the formation of peptic ulcers?
- NSAIDs
- Smoking
What is the most common presenting feature of peptic ulcer disease and what is the nature of this?
recurent abdominal pain - localisation to the epigastrium, relationship to food and episodic occurrence
What are the 3 key features of abdominal pain due to peptic ulcer?
- Localisation to epigastrium
- Relationship to food
- Episodic occurrence
What proportion of patients suffering with peptic ulcer experience occasional vomiiting?
40%
What is meant by a silent ulcer?
presenting for first time with anaemia from chronic undetected blood loss, abrupt haemtemesis or acute perforation
What is the preferred investigation to diagnose peptic ulcers?
endoscopy