Primary gastric lymphoma presenting with vitamin B12 deficiency and achlorhydria.

Gastric lymphoma is an uncommon condition, usually presenting with epigastric pain and/or dyspepsia. There is now good evidence that infection with Helicobacter pylori (Hp) is etiologically important. We report here a case of primary gastric lymphoma presenting with vitamin B12 deficiency anemia and achlorhydria in which there was evidence of previous, but not current, infection with Hp. Vitamin B12 deficiency was proven to be due to intrinsic factor deficiency. To our knowledge, this condition has not previously been reported.