Early Endoscopic Features of Suspected Autoimmune Gastritis in a Young Adult Male Patient: A Case Report.

Autoimmune gastritis, traditionally referred to as type A gastritis, is characterized by corpus-predominant atrophic gastritis caused by autoimmune mechanisms. Most cases are diagnosed in middle-aged or elderly individuals, as complications such as pernicious anemia and impaired absorption of iron and vitamin B12 typically manifest in advanced stages. Additionally, patients with autoimmune gastritis are often asymptomatic, making reports of early-stage endoscopic findings exceedingly rare. A 22-year-old male presented to our hospital with complaints of epigastric pain and lower back pain. He had undergone eradication therapy for Helicobacter pylori infection at another hospital three months prior to presentation. A urea breath test confirmed successful eradication of H. pylori. Endoscopic examination revealed extensive, sharply demarcated mucosal atrophy extending orally from the middle of the gastric body, while the gastric antrum showed no evidence of atrophy or intestinal metaplasia. Laboratory tests revealed a mild elevation in anti-parietal cell antibody levels, with a titer of 1:10, whereas serum gastrin and vitamin B12 levels remained within normal limits. Iron metabolism parameters were also normal. However, histopathological confirmation was unavailable, and thus a definitive diagnosis of autoimmune gastritis could not be established. This report presents a rare case of suspected early-stage autoimmune gastritis with distinctive endoscopic findings in a young male.