What is the best course of treatment for a patient with Helicobacter pylori (H. pylori) infection and how can transmission to a relative be prevented?

H. pylori Treatment and Prevention of Transmission to Relatives

Treat the infected patient with 14-day bismuth quadruple therapy (or rifabutin triple therapy if bismuth unavailable), and simultaneously test and treat all first-degree relatives living in the household to break the transmission cycle and reduce their gastric cancer risk. 1, 2

Treatment of the Infected Patient

First-Line Therapy Selection

Bismuth quadruple therapy for 14 days is the preferred empiric regimen when antibiotic susceptibility is unknown, as it avoids clarithromycin resistance issues and maintains efficacy even with metronidazole-resistant strains. 3, 2

The regimen consists of:

• Proton pump inhibitor (PPI) twice daily
• Bismuth subsalicylate
• Metronidazole 500 mg twice daily
• Tetracycline or amoxicillin 3, 4, 5

Alternative first-line options include:

• Rifabutin triple therapy for 14 days (suitable empiric alternative without penicillin allergy) 2
• Concomitant non-bismuth quadruple therapy (PPI + amoxicillin + metronidazole + clarithromycin) for 14 days in areas where bismuth is unavailable 3

The antibiotic combination must be chosen according to local H. pylori antibiotic resistance patterns, as antibiotic resistance is the most important factor responsible for falling eradication success rates. 3

Treatment Duration

All first-line therapies should be given for 14 days to maximize eradication success on the first attempt, which is critical to avoid retreatment, reduce costs, and minimize negative impacts on gut microbiota. 3

Confirmation of Eradication

Post-treatment test-of-cure is mandatory and should be performed no earlier than 4 weeks after cessation of treatment using either:

• Urea breath test (13C-UBT), or
• Stool antigen test 3, 1

Patients must be off antibiotics, bismuth, or PPIs for at least 2 weeks before testing to avoid false negatives. 1

Testing and Treating First-Degree Relatives

Who Should Be Tested

All first-degree relatives (parents, siblings, children) living in the same household should be tested for H. pylori, particularly when:

• The index patient has confirmed H. pylori infection 1
• There is a family history of gastric cancer (2-3 times increased risk; 10-fold if multiple relatives affected) 3, 1
• The patient experiences recurrent infection after treatment (suggesting ongoing intrafamilial exposure) 1

This represents a Grade A recommendation with level 1a-4 evidence from the European Society of Gastrointestinal Endoscopy. 1

Testing Methodology for Relatives

Use noninvasive testing methods:

• Urea breath test (UBT), or
• Stool antigen test 1

Ensure relatives are off antibiotics, bismuth, or PPIs for at least 2 weeks before testing. 1

Treatment of Positive Relatives

Treat all H. pylori-positive household members concurrently using the same 14-day bismuth quadruple therapy (or alternative first-line regimen) to:

• Break the transmission cycle and prevent reinfection of the index patient 1
• Protect family members from developing H. pylori-related diseases (peptic ulcer, gastric cancer—17% lifetime risk among infected individuals) 1
• Reduce the 2-3 times increased gastric cancer risk in first-degree relatives 3, 1

Transmission Prevention Strategies

Understanding H. pylori Transmission

H. pylori is moderately contagious within families through person-to-person transmission via:

• Oral-oral route (vomitus, possibly saliva) 6, 7
• Fecal-oral route 6, 7
• Contaminated water (especially in areas with untreated water) 6

First-degree relatives have 2-3 times increased risk of infection, rising to 10-fold when multiple family members are affected. 1

Practical Prevention Measures

While not explicitly detailed in guidelines, general hygiene measures based on transmission routes include:

• Avoid sharing utensils, cups, or toothbrushes during active infection 6
• Maintain good hand hygiene, especially after bathroom use 6
• Ensure adequate sanitation and access to clean water 6

Special High-Risk Situations

First-degree relatives of gastric cancer patients warrant particular attention and should be tested and treated even without symptoms due to substantially elevated cancer risk. 3, 1

Additional high-risk relatives requiring testing include those with:

• Family history of gastric neoplasia (MALT lymphoma, adenoma, cancer) 3
• Geographic origin from high gastric cancer incidence regions 1
• Age >45 years (gastric cancer risk increases significantly) 1

Critical Pitfalls to Avoid

Do not use monotherapy or suboptimal regimens (such as 7-day courses), as this increases antibiotic resistance and treatment failure. 3

Do not skip post-treatment confirmation testing, especially in complicated cases, as persistence of infection is a negative prognostic marker for ulcer recurrence and complications. 3

Do not test relatives too early after treatment—wait at least 4 weeks and ensure they are off acid-suppressing medications for 2 weeks to avoid false negatives. 1

Do not ignore recurrent infection after successful eradication, as this suggests ongoing intrafamilial exposure requiring household member testing and treatment. 1