Atrophy and atrophic gastritis: one step beyond the Sydney system.

An international workshop to evaluate the concepts of atrophy and atrophic gastritis was held in Houston in 1998. A consensus emerged that: 1) there is a phenotype of Helicobacter pylori-associated gastritis characterized by progressive loss of glands and intestinalization; 2) this phenotype is associated with increased risk of gastric ulcer and adenocarcinoma. This pattern must be consistently recognized are reproducibly diagnosed by histopathologists. The mucosal biopsy sampling suggested in the updated Sydney System were considered adequate to evaluate a patient for atrophic gastritis. Histopathologists were advised to refrain from making a diagnosis of "atrophic gastritis" unless moderate or severe unequivocal loss of gastric glands and/or moderate or severe metaplasia is found in at least 50% of the total gastric mucosa evaluated in the biopsy specimens. When atrophic or metaplastic changes appear to be more limited, "chronic gastritis with focal atrophy or metaplasia" should be diagnosed, and more extensive sampling should be obtained before the entity "atrophic gastritis" can be diagnosed. Particular attention was devoted to the issue of "unequivocal loss of gastric glands." In general, it was felt that it is difficult to be certain about loss of glands in the presence of moderate or severe inflammation, when one cannot be sure whether the glands have actually disappeared of have been displaced by the inflammatory infiltrate. In these circumstances, the term "indefinite for atrophy" can be used and the patient should be re-evaluated several months after the eradication of Helicobacter pylori infection.