Testing for the presence of Helicobacter pylori and subsequent eradication of the infection is a key aspect in the management of dyspepsia, which is now the largest single area of cost for primary care in the United Kingdom.1Since the bacterium was discovered in 1982 and its role in the aetiology of peptic ulcer disease became established, significant advances have been achieved in antimicrobial treatment with current regimens enabling successful eradication in 85 to 90% of patients.2 ,3 The reasons for treatment failure in the remaining small but significant group of infected individuals is often not clearly established but resistance to metronidazole and to clarithromycin are generally considered to be the primary factors. Both of these antibiotics are widely used in current regimens for eradicating H pylori although rates of resistance vary significantly from 10 to 50% for metronidazole, and from 0 to 15% for clarithromycin, depending on the population group surveyed.4 For instance, in a recent study of dyspeptics attending an open access endoscopy clinic in mid-Essex, we found pretreatment rates of 6% for clarithromycin …