What to think about when it's not Helicobacterpylori.

Gastric biopsies can be diagnostically challenging, particularly when evaluating inflammatory conditions beyond the settings of Helicobacter pylori gastritis and autoimmune gastritis. Recognition of specific morphological features associated with diagnostic entities can help identify less common causes of gastritis that might require different therapeutic interventions. Chemical (or reactive) gastropathy is another category of stomach injury that is associated with a broad differential, which may be narrowed, provided specific histological features are identified. Herein, we review features that may assist in identifying the culprit of gastric mucosal injury. Ultimately, pathologists must pay close attention to the composition of inflammation, distribution within the mucosa, and the severity and site of gastric injury.