No influence of age and gastric acid secretion on serum vitamin B12 concentration.

Serum vitamin B12 concentration, parietal cell antibodies (PCA), peak acid output vitamin B12 resorption capacity were determined in 76 patients (age 23 to 82 years). Gastroscopy was performed on all of these patients; guided biopsy was taken from 70 of them. No influence of the inflammatory changes in the gastric mucosa, sex or the presence of PCA on the serum vitamin B12 concentration were demonstrable in our patients, who all revealed a vitamin B12 resorption in the normal range. In particular we were unable to confirm the observation of Döscherholmen et al. (5) of a fall in serum vitamin B12 concentration with increasing age or decreasing PAO. Hence the estimation of the serum vitamin B12 concentration cannot be used as a screening test for selecting those patients suffering from chronic atrophic gastritis and achlorhydria, who should be monitored by gastroscopy and biopsy because of an increased risk of gastric cancer.