In a 43-year-old asymptomatic man with confirmed Helicobacter pylori infection, should all family members be tested for H. pylori?

Should Family Members Be Tested for H. pylori?

Yes, family members living in the same household as a patient with confirmed H. pylori infection should be tested, particularly if they have risk factors such as a family history of peptic ulcer disease or gastric cancer. 1

Strength of Recommendation for Household Testing

The Houston Consensus Conference provides a strong recommendation (91% expert agreement, moderate-level evidence) to test family members residing in the same household as patients with proven active H. pylori infections. 1 This approach serves three critical purposes:

• Protects other household members from initial infection or reinfection of the index patient 1
• Prevents progression to serious complications including peptic ulcer disease and gastric cancer through early detection and treatment 1
• Interrupts intrafamilial transmission, which is a well-documented mode of H. pylori spread 2, 3

Rationale: Why Household Transmission Matters

H. pylori demonstrates clear intrafamilial clustering, with person-to-person transmission occurring through oral-oral routes (vomitus, saliva) or fecal-oral routes. 3 The infection is particularly concentrated in families, making household contacts a high-risk group. 2 Approximately 50% of the world's population carries H. pylori, with most infections acquired during childhood and persisting for life if untreated. 4, 3

Asymptomatic family members can still harbor active infection and serve as transmission sources, making it critical not to ignore relatives without symptoms. 1

Which Family Members Warrant Testing Beyond Household Contacts

Even relatives not living in the same household should be considered for testing if they have:

• Family history of peptic ulcer disease (91% expert agreement, moderate evidence) 1
• Family history of gastric cancer (100% expert agreement, moderate evidence) 1

These relatives warrant testing because familial clustering of H. pylori-related diseases extends beyond just household transmission patterns. 1

Additional High-Risk Populations to Consider

• First-generation immigrants from high H. pylori prevalence countries (82% expert agreement) 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 1

Recommended Testing Approach for Asymptomatic Family Members

Use non-invasive testing with either urea breath test (UBT) or laboratory-based monoclonal stool antigen test. 1

Test Performance

• UBT: Sensitivity 88-95%, specificity 95-100% 1
• Stool antigen test: Sensitivity and specificity >90% when using laboratory-based validated monoclonal assays 1

Critical Pre-Test Preparation

To avoid false-negative results, ensure proper medication washout:

• Discontinue antibiotics and bismuth for at least 4 weeks 1
• Stop proton pump inhibitors (PPIs) for at least 7 days (ideally 2 weeks) 1
• Ensure 6-hour fasting before testing 1

Common Pitfalls to Avoid

• Do not use rapid office serology tests, which have disappointing accuracy (sensitivity 63-97%, specificity 68-92%) and cannot distinguish active infection from past exposure 1
• Do not assume asymptomatic relatives are uninfected—they can still transmit the bacterium 1
• Do not test while family members are taking PPIs unless the medication has been stopped for the appropriate washout period 1
• Do not skip testing of household contacts even if the index patient has been successfully treated, as reinfection can occur from untreated family members 1

Treatment Considerations After Positive Testing

If family members test positive, they should receive eradication therapy using first-line regimens such as 14-day bismuth quadruple therapy or concomitant therapy. 5 Treating infected household members reduces the risk of reinfection in the index patient and prevents disease progression in the relatives themselves. 1

Special Consideration: Children

H. pylori is typically transmitted during childhood, making testing of pediatric household contacts particularly important. 4, 2 The stool antigen test is safe in children, unlike radioactive testing methods. 5