Should a person with a close contact positive for Helicobacter pylori (H. pylori) infection undergo testing, especially if they have a history of gastrointestinal symptoms or underlying conditions?

Should Close Contacts of H. Pylori-Positive Individuals Be Tested?

Yes, household members and close family contacts of individuals with confirmed H. pylori infection should be tested, as this approach prevents transmission, reinfection, and progression to serious complications including peptic ulcer disease and gastric cancer. 1

Strength of Recommendation

The Houston Consensus Conference formally recommends testing family members residing in the same household as patients with proven active H. pylori infections, with 91% expert agreement and moderate-level evidence. 2, 1 This recommendation is based on the well-established person-to-person transmission pattern that occurs within families. 2

Why Test Household Contacts?

Prevention of Transmission and Reinfection

• Testing and treating infected family members protects other household members from initial infection and prevents reinfection of the index patient. 1
• H. pylori transmission occurs primarily through person-to-person routes (oral-oral or fecal-oral), with intrafamilial clustering being well-documented. 3
• Humans are the principal reservoir for H. pylori, and crowded living conditions facilitate transmission among family members. 3

Prevention of Serious Disease

• Early detection and treatment prevents progression to peptic ulcer disease, gastric cancer, and gastric MALT lymphoma. 1
• H. pylori gastritis is now formally recognized as an infectious disease that provides no proven benefits to the host and carries significant risk. 2
• Eradication can halt progression to atrophic gastritis and reduce gastric cancer risk. 4

Additional High-Risk Relatives to Consider

Beyond household contacts, testing should be extended to:

• Relatives with family history of peptic ulcer disease (91% expert agreement, moderate evidence). 2, 1
• Relatives with family history of gastric cancer (100% expert agreement, moderate evidence). 2, 1
• These relatives warrant testing even if they don't live in the same household, as familial clustering extends beyond just household transmission. 1

Recommended Testing Approach for Asymptomatic Contacts

First-Line Non-Invasive Tests

• Urea breath test (13C-UBT): Preferred test with sensitivity 88-95% and specificity 95-100%. 4, 5, 1
• Stool antigen test: Laboratory-based validated monoclonal test with sensitivity and specificity >90%. 5, 1

Tests to Avoid

• Do not use rapid office serology tests due to disappointing accuracy (sensitivity 63-97%, specificity 68-92%). 1
• Serology should only be used if validated laboratory testing with >90% sensitivity and specificity is available. 4

Critical Testing Preparation

To ensure accurate results, contacts must:

• Discontinue antibiotics and bismuth for at least 4 weeks before testing. 1
• Stop PPIs for at least 7 days before testing. 1
• Fast for 6 hours before urea breath testing. 1

Common Pitfalls to Avoid

• Do not assume asymptomatic relatives are uninfected: Asymptomatic individuals can still harbor the infection and serve as transmission sources. 1
• Do not delay testing: Early identification prevents both disease progression in the infected individual and transmission to others. 1
• Do not forget proper test preparation: Failure to discontinue PPIs or antibiotics leads to false-negative results. 1

Special Populations Requiring Enhanced Vigilance

Testing is particularly important for:

• First-generation immigrants from high H. pylori prevalence countries (82% expert agreement). 2, 5, 1
• Latino and African American populations in the United States, where H. pylori prevalence is 2.6-3.2 fold higher than the general population. 2, 1

Treatment After Positive Testing

If household contacts test positive:

• Treat with 14-day bismuth quadruple therapy or 14-day concomitant therapy (non-bismuth quadruple therapy). 4, 5
• Perform test of cure 6-8 weeks after treatment completion using urea breath test or stool antigen test. 4, 5
• Never use serology for post-treatment confirmation as antibodies remain elevated after eradication. 5