Inflammatory and Infectious Diseases of the Stomach and Duodenum

Abstract

Gastritis has a broad histopathologic, topographical, and etiological spectrum. Since Helicobacter pylori (H. pylori) was discovered in 1983, the conceptions of the etiology of a wide variety of gastric diseases have been changed as it has become apparent that infection with H. pylori is the major cause of them, including peptic ulcer and nonimmune chronic gastritis. To give consideration to all of these changes and to clarify diagnostic confusion, the guidelines for the classification and grading of gastritis, “the Sydney System,” was published in Sydney in 1990 and revised in 1994. The updated Sydney System emphasized the importance of combining topographical, morphological, and etiological information into a schema for reproducible and clinically useful diagnosis. It should be kept in mind that histopathologically, every single patient may be exposed to more than one etiological factor, resulting in more than one type of gastritis in a same patient. However, gastritis still is a complex and often confusing topic for clinicians and radiologists because of an evolving pathogenesis, varied diagnostic criteria, and, occasionally, poor imaging correlation. A simplified classification of gastritis, which is based on the current concepts, would be adjusted for a practical approach to radiologic evaluation as follows: erosive gastritis, H. pylori gastritis, chronic atrophic gastritis, hypertrophic gastritis, and miscellaneous types, including emphysematous, parasitic, and eosinophilic gastritis, gastric tuberculosis, and gastric sarcoidosis.