The histopathological changes due to chronic Helicobacter pylori infection are well characterized. Nevertheless, the clinical and pathological outcomes resulting from the cure of this infection remain incompletely described. In particular, the influence of eradication of H. pylori on nonulcer dyspepsia, the long-term effects of H. pylori eradication on gastric atrophy and intestinal metaplasia, and the role of H. pylori eradication in the prevention of gastric cancer are still unclear. We reviewed 38 studies reported between 1993 and 1999 on the outcome of various disorders related to H. pylori infection after successful eradication. There is general agreement concerning the regression of chronic gastritis, lymphoid follicles, and limited-stage lowi-grade MALT lymphomas of the gastric mucosa after eradication of H. pylori infection. Conversely, there are still major questions on whether H. pylori eradication improves the outcome of premalignant lesions, such as atrophy, intestinal metaplasia, and dysplasia. Finally, some extragastric idiopathic diseases seem to improve in consequence of the eradication of the infection, although there are still no definitive data to support this.