IntroductionPopulation-based eradication of Helicobacter pylori has been suggested to be cost-effective and is recommended by international guidelines. However, the potential adverse effects of widespread antibiotic use that this would entail have not been sufficiently studied. An alternative way to decrease gastric cancer mortality is by non-invasive search for precancerous lesions, in particular gastric atrophy; pepsinogen tests are the best currently available alternative. The primary objective of GISTAR is to determine whether H pylori eradication combined with pepsinogen testing reduces mortality from gastric cancer among 40–64-year-old individuals. The secondary objectives include evaluation of H pylori eradication effectiveness in gastric cancer prevention in patients with precancerous lesions and evaluation of the potential adverse events, including effects on microbiome.Methods and analysisIndividuals are recruited from general population (50% men) in areas with high gastric cancer risk in Europe and undergo detailed lifestyle and medical history questionnaire before being randomly allocated to intervention or control groups. The intervention group undergoes H pylori testing and is offered eradication therapy if positive; in addition, pepsinogen levels are detected in plasma and those with decreased levels are referred for upper endoscopy. All participants are offered faecal occult blood testing as an incentive for study participation. Effectiveness of eradication and the spectrum of adverse events are evaluated in study subpopulations. A 35% difference in gastric cancer mortality between the groups is expected to be detectable at 90% power after 15 years if 30 000 individuals are recruited. Biological materials are biobanked for the main and ancillary studies. The study procedure and assumptions will be tested during the pilot phase.Ethics and disseminationThe study was approved by the respective ethics committees. An independent Data Safety and Monitoring Board has been established. The findings will be published in peer-reviewed journals and presented at scientific meetings.Trial registration numberNCT02047994

The prevalence of H. pylori infection or atrophy remains high in Latvia. Determining the right cutoff value is critically important for pepsinogen-based atrophy detection in Europe in order to objectively stratify gastric cancer risk.

The prevalence of H.pylori was significantly higher among patients with reflux oesophagitis compared to patients with hyperaemic gastropathy alone. Adjusting for age the prevalence of H.pylori infection was not higher among symptomatic children compared to asymptomatic children of the same age.

The review summarizes the articles published on Helicobacter pylori in children between April 2007 and March 2008. Evidence is emerging in different populations including developing countries that the prevalence of H. pylori is declining in all age groups. The reasons for this are unclear but it is unlikely that treatment of infection or improvement in socioeconomic conditions fully explains the decline. For the first time, differences in the inflammatory response between adults and children have been well characterized in a group of adults and children from Chile with similar levels of H. pylori infection. This study suggests that the reduced inflammatory response to H. pylori at a cellular level in children could be the consequence of an enhanced Treg cell response, which in turn down-regulates H. pylori -induced inflammation. The publication of the Paediatric European Register for Treatment of Helicobacter pylori study (PERTH) is important as it demonstrates the advantages of different centers working in collaboration for the benefit of children. It also highlights the fact that while bismuth-based treatment is more effective than proton pump inhibitor-based treatment in children, bismuth preparations are not widely available for use in children.