Can Helicobacter pylori-associated dyspepsia be categorized as functional dyspepsia?

Evidence for an association between H. pylori and functional dyspepsia (FD) is uncertain. In the present review, we focused the special relevance of H. pylori infection to the development dyspepsia from the aspects of pathogenesis, clinical efficacy of eradication of H. pylori in the West and in the East. Although clinical trials conducted to evaluate the efficacy of H. pylori eradication treatment for FD, including non-ulcer dyspepsia (NUD), have yielded conflicting results, it is quite clear that H. pylori eradication treatment is effective at least in a subset of FD patients. In contrast to the previous results obtained in studies of Western populations, the result of a double-blind, randomized, placebo-controlled trial conducted in a Singapore suggests that patients with FD could benefit from H. pylori eradication therapy, with as much as a 13-fold increase in the chance of symptom resolution. Especially in Asia, H. pylori should not be overlooked when considering the pathophysiology of FD. H. pylori-associated dyspepsia might be dealt as a different disease entity from FD.