Overview
Helicobacter pylori (H. pylori) is a gram-negative spiral bacillus associated with peptic ulcer disease. To avoid the acidic environment of the stomach, it uses its flagella and burrows into the mucus lining to reach the epithelial cells underneath. It also produces urease which breaks down urea in the stomach to carbon dioxide and ammonia. Ammonia is alkaline and neutralises stomach acid, helping it to survive.
Epidemiology
- Generally, as age increases, the prevalence of H. pylori increases
- Around 50% of people globally have H. pylori present, therefore infection does not entirely equal disease
- Most cases of gastric ulcers are due to H. pylori, whereas nearly all cases of duodenal ulcers are caused by it
Presentation
Patients present with features of dyspepsia. Red flags must also be ruled out and if present, an appropriate referral should be made. See Dyspepsia for more information regarding presentation and referral criteria.
Investigations
The investigation of choice is a carbon-13 urea breath test. The patient drinks carbon-13 enriched urea which is then broken down by H. pylori into carbon dioxide and ammonia. The carbon dioxide will have carbon-13 in it which is tested:
- It should not be performed within 4 weeks of treatment with antibiotics or within 2 weeks of using proton pump inhibitors (PPIs) as these can mask results
- It may also be used for checking for H. pylori eradication. This is usually done if symptoms re-emerge.
Management
- 1st-line: 7-day course of PPI + amoxicillin + clarithromycin or metronidazole
- If allergic to penicillin: PPI + clarithromycin + metronidazole
Complications
- Gastric mucosa-associated lymphoid tissue (MALT) lymphoma:
- Eradication of H. pylori causes regression in around 80% of cases
