Influence of duodenal intrinsic factor on the absorption of labelled vitamin B12.

The intrinsic factor activity of powdered hog duodenal mucosa was confirmed by measurements of the absorption of labelled vitamin B 12 (Schilling-test) in 7 cases of Addisonian pernicious anaemia. In view of the fact that, according to earlier studies of the authors based on a bacteriological test, human duodenal juice also exhibits an intrinsic factor activity, it is suggested that the duodenal intrinsic factor may be involved in the pathogenesis of pernicious anaemia. The results of the Schilling-test are critically reviewed in the light of recent published evidence.