A case of nodular gastritis progression to autoimmune gastritis after 10 years of Helicobacter pylori eradication.

A 61-year-old female patient underwent upper gastrointestinal endoscopy, which confirmed the presence of Helicobacter pylori (H. pylori)-positive nodular gastritis (NG). Routine upper gastrointestinal endoscopy after H. pylori eradication revealed atrophic changes of the corpus, having gradually progressed over the 10 years after successful eradication. Serological and biopsy specimen examination showed hypergastrinemia (1200 pg/mL), positive anti-parietal cell antibody (with a titer of more 160), and endocrine cell micronests after 11 years of H. pylori eradication. The patient was diagnosed with autoimmune gastritis (AIG) based on endoscopic, serological, and histological findings. This is the first report of AIG diagnosed in a patient with NG over a long period of time after H. pylori eradication.