Pernicious anaemia: its pathogenesis in the light of the beneficial effect of duodenal intrinsic factor.

Oral ingestion of powdered duodenal mucosa with small doses of vitamin B12 proved efficient in four cases of untreated pernicious anaemia. The erythropoietic as well as the other responses were similar as those elicited by any reliable anti-pernicious drug. It has thus been confirmed that the growth factor demonstrated earlier in human duodenal juice by means of E. coli mutant corresponds in fact to the intrinsic factor. It is suggested that besides the deficiency of gastric intrinsic factor the duodenal intrinsic factor and the immune mechanisms neutralizing it are also involved in the pathogenesis. It has been shown that the aqueous extracts of hog stomach and duodenum differ in addition to their growth factor and nitrogen contents, also in aminoacid composition.