From the Guidelines
The urease breath test has a sensitivity of 88-95% and a specificity of 95-100% for detecting Helicobacter pylori infection. This test works by measuring carbon dioxide produced when H. pylori's urease enzyme breaks down urea labeled with either carbon-13 or carbon-14 1. The test is non-invasive, relatively quick, and can be used both for initial diagnosis and to confirm eradication after treatment.
Key Points to Consider
- The test's high sensitivity and specificity make it one of the preferred non-invasive methods for H. pylori detection in clinical practice 1.
- Patients should avoid antibiotics for 4 weeks before testing, proton pump inhibitors for 2 weeks, and bismuth preparations for 2 weeks, as these can cause false-negative results 1.
- Patients should also fast for 4-6 hours before the test to ensure optimal accuracy.
- False positives can occasionally occur with other urease-producing organisms in the oral cavity or stomach.
Test Characteristics
- Sensitivity: 88-95%
- Specificity: 95-100% The urease breath test is a reliable and efficient method for detecting H. pylori infection, with a high sensitivity and specificity, making it a valuable tool in clinical practice 1.
From the Research
Urease Breath Test Sensitivity and Specificity
- The sensitivity and specificity of the urease breath test can vary depending on the study and the specific test used.
- According to the study by 2, the sensitivity of the 13C-urea breath test was 97.4% (95% CI, 95-99%) and the specificity was 99.5% (98-100%) when using a cut-off point of -13.
- Another study by 3 reported a sensitivity of 89% and a specificity of 73% for the urea breath test.
- A systematic review by 4 found that the urea breath test had a high diagnostic accuracy, with a sensitivity of 0.94 (95% CI 0.89 to 0.97) and a specificity of 0.90 (median from studies across the four tests).
Factors Affecting Test Accuracy
- The use of proton pump inhibitors (PPIs) can affect the accuracy of the urease breath test, with some studies suggesting that PPIs can cause false-negative results 5.
- However, other studies have found that the stool antigen test, which is less likely to be affected by PPIs, can be a reliable alternative 6.
- The choice of test and the specific protocol used can also impact the sensitivity and specificity of the urease breath test.
Comparison with Other Tests
- The urease breath test has been compared to other diagnostic tests for Helicobacter pylori infection, including serology and stool antigen tests.
- A study by 3 found that the stool antigen test had a higher sensitivity (96%) and specificity (83%) compared to the urea breath test (89% and 73%, respectively).
- The systematic review by 4 found that the urea breath test had a higher diagnostic accuracy compared to serology and stool antigen tests.