[Helicobacter pylori eradication. Therapeutic evolution, value of complementary studies]

Eradication of Helicobacter pylori is needed for patients with a gastroduodenal ulcer associated with H. pylori gastritis. Eradication modifies the natural history of the disease and greatly reduces the risk of recurrence. Eradication is also indicated for patients with MALT lymphoma with a low degree of malignancy. Systematic eradication of H. pylori would not be necessary for patients with dyspepsia associated with H. pylori gastritis since a beneficial effect is achieved in only 5% of the treated patients. Systematic eradication in order to reduce the incidence of gastric adenocarcinoma is not recommended.

Direct tests (urease, pathology) provide the diagnosis of H. pylori gastritis. Indirect tests (13C-labeled urea respiratory test) can be most useful to determine the efficacy of eradication treatments.

A tri-therapy regimen given for 7 days combining a double-dosed proton pump inhibitor, amoxicillin (2 g/d), and clarithromycin (0.5 g b.i.d) is used to eradicate H. pylori. With this regimen, the mean rate of eradication achieved in France is 67%. The principal causes of failure are poor compliance and bacterial resistance to clarithromycin. Metronidazole (1 g/d) can be used for patients allergic to penicillin. A second cycle can be prescribed in case of failure, substituting metronidazole for clarithromycin.

Eradication treatment is prescribed for patients with an ulcer after confirmation of infection by one or two direct tests. Treatment efficacy can be assessed by the respiratory test for patients with a duodenal ulcer but is not systematically needed. Biopsy of a gastric ulcer can also provide an assessment of treatment efficacy. For patients with a non-complicated duodenal ulcer, antisecretion treatment is not required in addition to eradication treatment.