Diagnosis of Helicobacter pylori infection. When to use which test and why.

Tests for the detection of Helicobacter pylori differ in many respects. The choice of test depends on the clinical situation. In symptomatic patients, endoscopy is an important tool for diagnosing peptic ulcer disease or other gastroesophageal lesions. A biopsy-based detection system for H. pylori, such as the rapid urease test, microscopy or culture of the organisms, is therefore appropriate. The diagnostic sensitivity will increase if more than one of these is performed. In asymptomatic patients, a non-invasive test should be used, and serology with a titre is suitable in this situation. If the results prove positive, confirmation of H. pylori infection is recommended using a urea breath test. Patients who have previously received H. pylori eradication therapy and present with a recurrence of symptoms should receive further eradication therapy if they are still H. pylori-positive, even if no endoscopic abnormality is found. A non-invasive test should be used and the urea breath test is the best option in these individuals, as serology is not suitable within 6-12 months of eradication therapy. If the breath test is unavailable, a biopsy-based test should be used. The outcome of H. pylori eradication therapy should be assessed using a non-invasive test. The urea breath test is appropriate, as serology is not suitable post-treatment. The breath test should be performed 4-8 weeks after the end of treatment to avoid false-negative results caused by temporary suppression of the infection. If the breath test is unavailable, a serology with a titre or a biopsy-based test must be used, at least 6-12 months after the end of treatment.