From the Guidelines
Diagnosing H. pylori infection requires a combination of non-invasive and invasive tests. The choice of test depends on the clinical circumstances, likelihood ratio of positive and negative tests, cost-effectiveness, and availability of tests 1.
Non-Invasive Tests
- Urea breath test (UBT): This is a preferred initial test, with high sensitivity and specificity 1.
- Stool antigen test (SAT): This test is also highly sensitive and specific, and can be used as an alternative to UBT 1.
- Serology: Although serology is available, it is not recommended for diagnostic purposes due to its low specificity and sensitivity, and the fact that it remains positive long after the infection has been eradicated 1.
Invasive Tests
- Endoscopy with biopsy: This is usually reserved for patients with symptoms suggestive of peptic ulcer disease or gastric cancer, and those who have failed non-invasive testing 1.
- Histological examination: This can be used to detect H. pylori infection, especially in patients with gastric biopsy samples 1.
- Culture: This can be used to detect H. pylori infection, especially in patients who have failed eradication therapy and need culture and antimicrobial sensitivity testing 1.
It is essential to choose the right test based on the clinical circumstances and patient preferences. The diagnostic strategy should reflect not only the clinical indication but also the local availability and costs of the different tests 1.
From the Research
Diagnostic Methods for Helicobacter pylori Infection
The diagnosis of Helicobacter pylori (H. pylori) infection can be achieved through various methods, which can be classified as invasive or non-invasive. The choice of method depends on several factors, including the need for upper endoscopy, clinical circumstances, sensitivity, and specificity 2, 3.
Invasive Diagnostic Methods
- Endoscopy with biopsy is considered the gold standard for diagnosing H. pylori infection, allowing for the collection of tissue samples for histological examination and culture 2, 4.
- Histology can detect H. pylori and provide information on the degree of gastric mucosa inflammation and precancerous lesions 2, 4.
- Cultures from gastric biopsies are recommended for antibiotic susceptibility tests 2.
Non-Invasive Diagnostic Methods
- Urea breathing test is a non-invasive test that can accurately determine H. pylori status, with high sensitivity and specificity 2, 5.
- Stool antigen test is a non-invasive test that can detect H. pylori infection, but its reliability may be lower in patients with bleeding peptic ulcers 5, 6.
- Serology can be used for initial screening and epidemiological studies, but its sensitivity and specificity may vary 2, 5.
Novel Diagnostic Technologies
- Visual endoscopy using blue laser imaging (BLI), linked color imaging (LCI), and magnifying endoscopy can aid in the diagnosis of H. pylori infection 2.
- Artificial intelligence can predict H. pylori status based on endoscopic images, showing promise as a novel diagnostic tool 2.
Limitations and Considerations
- The interpretation of histological slides has significant interobserver variability, even in experienced hands, and may be inaccurate at times 5.
- The H. pylori stool antigen test may not be reliable for diagnosing H. pylori infection in patients with bleeding peptic ulcers 6.
- The choice of diagnostic method should be based on the individual patient's clinical circumstances and the availability of resources 2, 3.