When treatment of Helicobacter pylori infection is considered, a relia
ble diagnosis is essential. Different biopsy-based invasive diagnostic
tests are available for diagnosis in the individual patient. Non-inva
sive tests are of value in epidemiological studies, and have a role in
the follow-up of treatment. In this review the sensitivity, specifici
ty and appropriateness of all available tests for the diagnosis of inf
ection in the individual patient are discussed.