H. pylori Diagnosis & Management
Antimicrobial Susceptibility Testing: When, How, Why — Based on Graham DY & Moss SF. Am J Gastroenterol 2022;117:524–528
- Understand why antimicrobial susceptibility testing is now essential for H. pylori management
- Know when, how, and where to obtain susceptibility testing (biopsy vs. stool; culture vs. NGS)
- Apply the treatment algorithm: empiric vs. susceptibility-based therapy selection
- Prescribe correct optimized regimens based on susceptibility results
- Counsel patients effectively and perform test-of-cure after every treatment
Sections
Why susceptibility testing matters
Helicobacter pylori gastritis is now recognized as an important transmissible infectious disease of the stomach. Increasing antimicrobial resistance worldwide has led to declining eradication success, necessitating susceptibility testing as a key tool in management.
• "Best guess" based on experience
• Empiric prescribing of clarithromycin, levofloxacin, or metronidazole triple therapies
• No test-of-cure feedback loop
→ Antibiotic misuse & low eradication rates
• Test (gastric biopsy or stool) before prescribing
• Culture or PCR / Next-Generation Sequencing (NGS)
• Guide regimen to confirmed susceptibility
→ Avoid inappropriate antibiotic use & improve cure rates
Treatment success requires optimized regimens — defined as consistently achieving cure rates of ≥95% in adherent patients with susceptible infections.
• Use susceptibility-based therapy as the primary strategy
• If empiric therapy is used: only choose regimens proven to cure >90% locally
• Always perform test-of-cure after every treatment attempt
Graham & Moss. Am J Gastroenterol 2022;117:524–528
>95%
Target cure rate with optimized susceptibility-based therapy
<90%
Trigger to obtain susceptibility testing for empiric regimens
6
Antibiotics to test: amoxicillin, metronidazole, tetracycline, levofloxacin, clarithromycin, rifabutin