CLINICAL REVIEW Treatment of Helicobacter pylori infection L Fuccio, 1 L Laterza, 1 R M Zagari, 1 V Cennamo, 1 D Grilli, 2 Franco Bazzoli 1 Helicobacter pylori is one of the most common human infections, and about half of the world’s population carries this organism. Since its discovery in 1984, H pylori has been recognised as a major cause of several upper gastrointestinal diseases. 12 As with other chronic infectious diseases, several antibiotics must be given simultaneously and sometimes repeated courses of different combinations of antibiotics are needed to eradicate H pylori. Eradicating H pylori is still a challenge, however, because of the rapidly increasing prevalence of multidrug resistant strains worldwide. In recent years, several randomised controlled trials and meta-analyses have proposed new regimens and treatment strategies for H pylori infection. This review will discuss the available treatment strategies for H pylori infection and help identify the most effective one. How common is H pylori infection? The prevalence of H pylori varies widely, with more than 80% of adults being infected in Japan and South America compared with around 40% in the United Kingdom and 20% in Scandinavia. 3 Epidemiological evidence suggests that many people acquire the infection in childhood—social deprivation, household crowding, and number of siblings are important risk factors. The prevalence of infection increases with age, although this may be largely a cohort effect. Poorer socioeconomic conditions 60 years ago meant most children were infected with H pylori. Although most people over 60 are H pylori positive only 10-20% of children are infected today. This is consistent with the reduction over time of H pylori related diseases such as peptic ulcer and gastric cancer. Why should I treat H pylori infection? Several conditions have been linked to H pylori infection, and its eradication has consistently been shown to be beneficial (table). Meta-analyses of comparative trials have shown that, when compared with no treatment, eradication provides significant benefit in terms of the healing of peptic ulcers and the prevention of recurrence. 4 Eradication also prevents recurrent bleeding from peptic ulcers. Several non-randomised observational and prospec- tive studies have supported the role of H pylori infection in the development of mucosa associated lymphoid tissue lymphoma. These studies have also shown that eradication of H pylori provides durable remission in patients with low grade mucosa associated lymphoid tissue lymphoma. As reported in our previous review, eradicating H pylori provides significant benefit to patients with uninvestigated dyspepsia without alarm features. 5 The association between gastric cancer and H pylori infection has been based on large scale epidemiological studies, meta-analyses of case-control studies, and experimental models. 2 However, it is not known whether eradicating H pylori infection can reduce the risk of developing gastric cancer. One large rando- mised placebo controlled study showed that in patients without precancerous lesions (atrophy, intestinal meta- plasia, or dysplasia) at study entry, eradication of H pylori significantly decreased the development of gastric cancer compared with placebo. 6 European guidelines have proposed that eradication should be considered not only in patients who already have gastric cancer, but also in those at increased risk of developing gastric cancer, such as first degree relatives of patients with gastric cancer. 7 American guidelines consider being at high risk for gastric cancer to be a controversial indication for diagnosing and treating H pylori infection. 8 Asia-Pacific consensus guidelines recently suggested that H pylori infection should be widely screened for and treated to reduce the risk of gastric cancer in populations at high risk. 9 What are the available treatment regimens and how can we choose between them? Dual or triple regimens? Many eradication treatments have been proposed (box). Monotherapies and dual therapies—usually a proton pump inhibitor and one antibiotic—have always had disappointing results. 10 11 A highly effective proton pump inhibitor based triple therapy—composed of omepra- zole, tinidazole, and clarithromycin—was first reported in 1993. 12 Shortly after, a similar triple therapy, which used amoxicillin instead of the nitroimidazole and had a UNANSWERED QUESTIONS Which is the most cost effective strategy? Does the eradication rate differ between patients with peptic ulcer disease and non-ulcer dyspepsia? What factors predict treatment failure other than antibiotic resistance and adherence to therapy? 1 Department of Internal Medicine and Gastroenterology, University of Bologna, 40138, Bologna, Italy 2 Department of Economics, University of South Florida, FL 33620, USA Correspondence to: F Bazzoli franco.bazzoli@unibo.it Cite this as: BMJ 2008;337:a1454 doi:10.1136/bmj.a1454 746 BMJ | 27 SEPTEMBER 2008 | VOLUME 337 For the full versions of these articles see bmj.com