A granuloma is an organized aggregation of combined histiocytic, lymphocytic, and plasma infiltrate (granulomatous inflammation). When this organized collection of cells is identified in the stomach, it is referred to as granulomatous gastritis.
This topic review will discuss the epidemiology, etiology, histopathology, and diagnosis of granulomatous gastritis. The classification of gastritis and causes of acute and chronic gastritis are presented separately. (See "Classification and diagnosis of gastritis and gastropathy" and "Acute and chronic gastritis due to Helicobacter pylori".)
Granulomatous gastritis is rare, with an incidence of 0.08 to 0.35 percent of gastritis cases [1-4]. In the largest reported series, only 56 cases were diagnosed after review of 15,947 biopsies/resections .
Granulomatous gastritis is a subtype of chronic gastritis and can be subclassified based on the etiology into infectious, noninfectious, and idiopathic granulomatous gastritis .
A specific cause can be identified in most patients found to have granulomatous gastritis [2,6]. The most likely causes vary by geography and ethnicity. Most cases of granulomatous gastritis in the western hemisphere are noninfectious in etiology with the most common causes in adults and children being Crohn disease and sarcoidosis [2,3]. In contrast, in developing countries, infectious diseases, particularly Mycobacterium tuberculosis, are the most common cause of granulomatous gastritis .