Helicobacter pylori infection
Helicobacter pylori is a urease-producing, gram-negative spiral bacillus that colonizes the gastric mucosa and causes chronic active gastritis, peptic ulcer disease, gastric adenocarcinoma, and gastric MALT lymphoma. Active infection is diagnosed by urea breath test, monoclonal stool antigen, or gastric biopsy, every positive result is treated (bismuth quadruple therapy for 14 days preferred), and cure is confirmed by nonserologic testing at least 4 weeks after treatment.
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What this article covers
- Overview
Definition: chronic infection of the gastric mucosa by Helicobacter pylori, a fastidious, gram-negative, spiral-shaped, flagellated bacillus that lives beneath and within the gastric mucus layer and produces urease.
- Epidemiology
Prevalence rises with age in the United States: about 10% of people younger than 30 years and 60% of those older than 60 years are infected.
- Risk factors
Childhood in, or emigration from, a high-prevalence region: most infection is acquired early in life in developing countries.
- Pathophysiology
Survival in acid: urease splits urea into ammonia and carbon dioxide, and ammonia buffers acid around the organism and incites inflammation.
- Clinical features
Not a clinical diagnosis: infection produces no specific symptom pattern, so suspicion rests on the conditions it causes and diagnosis always requires a test of active infection.
- Differential diagnosis
Gastric adenocarcinoma: alarm features or age 60 years and older, with a mass or ulcer on endoscopy and malignant biopsy (gastric cancer).
- Diagnosis
Active infection is confirmed by a positive 13C-urea breath test, monoclonal stool antigen test, or gastric biopsy (histology with special stains, or rapid urease test); there is no severity grading…
- Management
First, treat every patient with active infection, choosing the first course carefully: the first course offers the best chance of cure, so base the choice on prior macrolide exposure for any reason…
- Complications
Gastric adenocarcinoma: the most serious consequence, through the atrophy, metaplasia, and dysplasia sequence; H.
- Prognosis
Eradication is curative: it heals about 90% of H.
- Prevention
Test and treat in these indications: Active peptic ulcer disease, or prior ulcer without documented cure.
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Related articles
- Peptic ulcer disease
Peptic ulcer disease is a mucosal break in the stomach or duodenum caused chiefly by Helicobacter pylori infection or NSAID use, diagnosed by upper endoscopy with biopsy of gastric ulcers to exclude malignancy. Treatment eradicates H. pylori when present, stops the ulcerogenic drug, and heals the ulcer with a proton pump inhibitor, while its complications of bleeding, perforation, and obstruction drive most of its morbidity.
- Dyspepsia
Dyspepsia is chronic or recurrent epigastric pain, burning, postprandial fullness, or early satiety that is organic when a structural, metabolic, or drug cause is found and functional when Rome IV criteria are met after a negative workup. Management starts with an alarm-feature screen that mandates prompt upper endoscopy, then test-and-treat for Helicobacter pylori, then an empiric proton pump inhibitor trial, reserving a tricyclic or prokinetic agent for confirmed functional disease.
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