Extreme hypergastrinemia caused by atrophic gastritis and Helicobacter pylori infection--a case report.

We present a case with extremely high serum gastrin induced by atrophic gastritis and Helicobacter pylori infection. The patient, a 95-year-old male, was diagnosed with idiopathic chronic diarrhea. During diagnostic work-up, his fasting serum gastrin was up to 2078 pg/mL. The secretin test was negative for gastrinoma. Octreotide scan showed no suspicious lesion except for diffuse faint uptake over the gastric antrum on the 48-hour-delay film. Gastric acidity test revealed achlorhydria. On histology examination, atrophic gastritis with Helicobacter pylori infection was found in the gastric body, but the antral mucus was normal with a slight increase in gastrin-secreting cells. To our knowledge, such extremely high serum gastrin induced by atrophic gastritis and Helicobacter pylori infection has never been reported before.