What are the recommended diagnosis and treatment options for Helicobacter pylori infection?

Diagnosis and Treatment of Helicobacter pylori Infection

The most effective approach for diagnosing active H. pylori infection is using either the urea breath test (UBT) or stool antigen test, while treatment should follow a "test and treat" strategy with triple therapy (amoxicillin, clarithromycin, and proton pump inhibitor) as first-line treatment for 14 days. 1, 2

Diagnostic Methods

Non-invasive Testing (Preferred)

• Urea Breath Test (UBT) is considered the most accurate non-invasive test with excellent sensitivity (94.7-97%) and specificity (95-95.7%) 1
• Stool Antigen Test directly detects H. pylori bacterial antigens in stool specimens with sensitivity and specificity of approximately 93%, comparable to UBT 1, 3
• Both UBT and stool antigen tests detect active infection rather than just past exposure, making them valuable for both initial diagnosis and confirmation of eradication 1, 4
• Serological tests should NOT be used as primary diagnostic method as they:
  • Cannot distinguish between active infection and past exposure 1
  • Have inadequate accuracy (averaging only 78%) for clinical use 1
  • Remain positive long after infection clearance 1, 5

Invasive Testing (When Endoscopy is Indicated)

• Rapid Urease Test provides quick results during endoscopy 1
• Histology allows visualization of bacteria and assessment of mucosal damage 1
• Culture permits antimicrobial susceptibility testing, especially valuable after treatment failure 1
• PCR can detect H. pylori and antibiotic resistance directly from biopsies 1

Treatment Recommendations

First-line Treatment Options

• Triple therapy: 1 gram amoxicillin, 500 mg clarithromycin, and 30 mg lansoprazole, all given twice daily for 14 days 2
• Dual therapy: 1 gram amoxicillin and 30 mg lansoprazole, all given three times daily for 14 days 2

Important Treatment Considerations

• Proton pump inhibitors should be stopped for at least 2 weeks before testing to avoid false-negative results 1, 6
• Confirmation of eradication should be performed no earlier than 4 weeks after completion of treatment 1
• UBT or stool antigen test (not serology) should be used to confirm eradication 1, 7

Indications for Testing

Primary Indications

• Active peptic ulcer disease (gastric or duodenal ulcers) 1
• History of peptic ulcer disease, especially with complications like bleeding 1
• Gastric MALT lymphoma 1
• Uninvestigated dyspepsia in patients under 50 years without alarm symptoms (using "test and treat" strategy) 1, 8
• Patients requiring long-term PPI therapy (>1 year) 1
• Atrophic gastritis or intestinal metaplasia 1

When to Use Endoscopy and Invasive Testing

• Patients with alarm symptoms (bleeding, weight loss, dysphagia, palpable mass, malabsorption) 8, 1
• Older patients (≥50 years) with new-onset dyspepsia due to increased risk of malignancy 1
• Patients who have failed eradication therapy, especially when culture and antimicrobial sensitivity testing are needed 1
• In regions with high clarithromycin resistance, before first-line treatment if standard clarithromycin-containing triple therapy is being considered 1

Common Pitfalls to Avoid

• Using serology tests for confirmation of eradication (antibodies remain elevated after H. pylori elimination) 1, 7
• Failing to stop PPIs before testing (can cause false-negative results in all tests except serology) 1, 6
• Using rapid in-office serological tests (limited accuracy) 1
• Testing too soon after treatment completion (should wait at least 4 weeks) 1

Special Populations

• In areas with high prevalence of gastric cancer, H. pylori testing followed by endoscopy in positive patients may be appropriate 1
• In patients with bleeding ulcers, H. pylori eradication treatment should be started at reintroduction of oral feeding 1
• Confirmation of H. pylori eradication is strongly recommended in complicated peptic ulcer disease, gastric ulcer, and cases of low-grade gastric MALT lymphoma 1