What remaining questions regarding Helicobacter pylori and associated diseases should be addressed by future...

A variety of questions regarding Helicobacter pylori need to be addressed by future research. Further investigations are needed on the relationship between H. pylori and gastric cancer. In particular, the mechanism of the interaction between H. pylori infection and host genetic factors and dietary factors that lead to the cancer need to be unraveled. Also, the reversibility of cancer-associated abnormalities (e.g., hypochlorhydria, atrophy, and intestinal metaplasia) by eradication of H. pylori needs to be determined. Noninvasive means of identifying H. pylori-positive subjects at high risk of developing gastric cancer are required for such subjects to be targeted for eradication therapy. Further studies are also required on the interactions between H. pylori and proton pump inhibitor therapy that might predispose to cancer. There is considerable interest in the possibility of noninvasive H. pylori testing replacing endoscopy in determining management of nonelderly patients with uncomplicated dyspepsia unassociated with nonsteroidal anti-inflammatory drugs (NSAIDs). Randomized studies comparing endoscopy vs. noninvasive H. pylori testing in this situation are required with comprehensive outcome measures. Improvement in eradication therapy is required and will depend on the development of more effective and specific antibiotics and therapeutic vaccines. Wide-scale elimination of the infection will depend on preventing its spread from person to person. Achieving this will require further knowledge of its mode of transmission, particularly in childhood, and the development of prophylactic vaccines. Further studies are required to define the role of H. pylori infection in other diseases, including predisposition to enteric infection in the developing world as a result of H. pylori-induced chronic hypochlorhydria, nonulcer dyspepsia, pernicious anemia, atherosclerosis, and NSAID-related ulcer disease. Finally, we need to know whether H. pylori infection may be beneficial in certain circumstances and whether eradicating the infection may be disadvantageous to some subjects.