From the Guidelines
To confirm H. pylori eradication after therapy, testing should be performed at least 4 weeks after completion of antibiotic treatment and at least 2 weeks after stopping proton pump inhibitors (PPIs) using a urea breath test or stool antigen test, as recommended by the most recent and highest quality study 1.
Importance of Confirming Eradication
Confirming H. pylori eradication is crucial to prevent recurrent ulcers, continued gastritis, and potential progression to more serious conditions such as MALT lymphoma. The urea breath test is the most reliable non-invasive test, with high sensitivity and specificity 1. Stool antigen testing is an acceptable alternative.
Testing Recommendations
- Testing should be performed at least 4 weeks after completion of antibiotic treatment and at least 2 weeks after stopping PPIs 1.
- Blood antibody tests should not be used for confirmation as antibodies can remain positive for months or years after successful eradication 1.
- For patients who require endoscopy for other reasons, biopsy-based testing can be performed, including rapid urease test or histology 2.
Clinical Considerations
- Testing for eradication is particularly important in patients with complicated ulcer disease, MALT lymphoma, or persistent symptoms despite therapy 2, 1.
- If the initial test confirms persistent H. pylori infection, second-line therapy with a different antibiotic regimen should be initiated 2, 1.
- Patients should be instructed to avoid antibiotics for 4 weeks and PPIs for 2 weeks before testing to prevent false-negative results 1.
From the FDA Drug Label
H. pylori status was determined by CLOtest®, histology and culture in all three studies. For a given patient, H. pylori was considered eradicated if at least two of these tests were negative, and none was positive. H pylori eradication was defined as no positive test (culture or histology) at 4 weeks following the end of treatment, and two negative tests were required to be considered eradicated of H. pylori.
To confirm H. pylori eradication after therapy, the following methods can be used:
- CLOtest
- Histology
- Culture At least two of these tests should be negative, and none positive, to consider H. pylori eradicated. Additionally, two negative tests are required at 4 weeks following the end of treatment to confirm eradication 3.
From the Research
Methods for Confirming H. pylori Eradication
- The urea breath test (UBT) and the Helicobacter pylori antigen stool test (HpSA) are recommended for monitoring H. pylori infection after treatment 4.
- The UBT is considered more accurate than the HpSA, with fewer false positive and false negative results 4.
- Proton pump inhibitor therapy can lead to false-negative H. pylori test results, and treatment should be stopped for 1-2 weeks prior to testing if possible 5, 6.
- A novel stool antigen test has been developed, showing high sensitivity and specificity for detecting H. pylori infection, and may be useful for diagnosing H. pylori infection after eradication therapy 7.
Diagnostic Tests
- The UBT is a non-invasive method for detecting H. pylori infection, with high accuracy, specificity, and rapid results 8.
- The 13C-UBT is preferred over the 14C-UBT due to its non-radioactive nature and higher diagnostic accuracy 8.
- The HpSA test is less accurate than the UBT, but can still be used as a non-invasive method for detecting H. pylori infection 4.
- Endoscopy with biopsy is an invasive method for detecting H. pylori infection, but can provide accurate results and is recommended for patients with discordant or indeterminate test results 4, 5.
Test Interpretation
- Cut-off values for the UBT and HpSA test should be carefully considered to enhance diagnostic precision 4, 8.
- Patients with discordant or indeterminate test results should undergo repeat endoscopy with multiple gastric biopsies to confirm H. pylori eradication 4.
- The presence of coccoid forms of H. pylori does not cause false positive HpSA results 4.