An Evaluation of Endoscopic Images from Over 15 Years Prior to the Diagnosis of Autoimmune Gastritis: A Report of Three Patients

A Case of Autoimmune Gastritis and Hepatitis with Enlarging Gastric Polyps after Reducing the Dose of Prednisolone

Autoimmune gastritis is immune-mediated gastritis that destroys the oxyntic mucosa. Autoimmune hepatitis is an inflammatory liver disease caused by an autoimmune reaction. These diseases share similar pathogeneses as organ-specific autoimmune disorders; however, cases involving both diseases are quite rare and scarcely reported. Herein, we report a patient with concurrent autoimmune gastritis and hepatitis who developed enlargement of hyperplastic polyps and progression of gastric atrophy. The patient was a 79-year-old female referred to our hospital for the treatment of hyperplastic polyps detected on a follow-up upper gastrointestinal endoscopy. The patient's previous upper gastrointestinal endoscopy from 3 years prior revealed small hyperplastic polyps and no mucosal atrophy. However, the current upper gastrointestinal endoscopy revealed three 10-mm red polyps, severe mucosal atrophy in the corpus, and mild atrophy in the antral area. In addition, biopsy samples from the gastric body revealed decreased parietal cells and diffuse lymphocytic infiltration of the deep mucosa. Further, chromogranin A-positive endocrine cell micronests and enterochromaffin-like cell hyperplasia were detected. After confirming the diagnosis of autoimmune gastritis, endoscopic mucosal resection was performed for all the polyps, which were histopathologically diagnosed as hyperplastic polyps without malignancy. Therefore, clinicians should consider autoimmune gastritis for enlarged hyperplastic polyps and gastric atrophy progression.

Rapid Progression of Autoimmune Gastritis after Helicobacter pylori Eradication Therapy: A Case Report

We herein report a case of autoimmune gastritis (AIG) with rapid progression after Helicobacter pylori eradication therapy. The patient's previous gastritis had followed the course of type B gastritis before eradication therapy for many years. Immediately after eradication, we diagnosed her with AIG and carefully followed changes in the endoscopic and histopathological findings and serum markers. All of these clinical findings showed significant atrophic progression in the corporal area for approximately three years. We concluded that H. pylori eradication therapy exacerbated AIG in this case.

Increase of Deep Intraepithelial Lymphocytes in the Oxyntic Mucosa of Patients With Potential and Overt Autoimmune Gastritis

Pathological correlates of potential autoimmune gastritis (AIG), defined by anti-parietal cell antibody (PCA) positivity in the absence of gastric atrophy, have never been described. We herein aimed to assess intraepithelial lymphocyte (IEL) infiltration in gastric corpus of AIG patients. From 2000 to 2021, among 53 potential AIG patients, we focused on nine (median age 61 years, IQR 53-82; four females) who subsequently developed overt AIG. IEL infiltration of the oxyntic mucosa was assessed before and after developing overt AIG by measuring deep and superficial CD3+ IEL. AIG patients with different degrees of corpus atrophy, healthy controls (HC), active H. pylori gastritis, celiac disease (CD), and Hashimoto’s thyroiditis patients were included as controls. Of note, deep, but not superficial, CD3+ IEL count was higher (p<0.001) in potential AIG compared to HC and H. pylori gastritis. Deep CD3+ IEL infiltration did not change before or after the evolution into atrophy (median 9.6, IQR 8.8-12.4, vs 11.3, IQR 9.4-12.9). No difference was found in deep CD3+ IEL infiltration among potential, mild, and severe AIG, and compared to Hashimoto’s thyroiditis or CD. A deep CD3+ IEL cut-off of >7/100 epithelial cells allowed discrimination of any AIG stage and severity (AUC=0.842). We conclude that an increased deep CD3+ IEL infiltration of the oxyntic mucosa could represent a marker of potential AIG. Prospective studies including a larger number of potential AIG patients are needed.