title: Crohn's disease and vitamin B12 metabolism.
abstract: The concentrations of vitamin B12, its analogs, and the haptocorrin and transcobalamin carriers in 21 patients suffering from Crohn's disease and a group of controls (20 adults) were measured. There were no significant differences in the mean values for vitamin B12, total corrinoids (vitamin B12 + analogs), or vitamin B12 or total corrinoids bound to haptocorrin or transcobalamin of the Crohn's and control patients. There was a significant increase in the binding capacity of transcobalamin in the Crohn's patients compared to the controls (P < 0.001), but there was no difference in the binding capacities of haptocorrin. The serum concentrations of the markers of vitamin B12 status, homocysteine and methylmalonic acid, showed an increase (P < 0.01) in homocysteine in the Crohn's disease patients, but no change in methylmalonic acid. As the hyperhomocysteinemia was associated with normal folate concentrations, there may have been a defect in the activation of the enzyme due to altered intracellular vitamin B12 status.
authors.affiliation: INSERM Unit 308, Faculté de Médecine, Vandoeuvre, France.
authors.forename: D
authors.initials: D
authors.lastname: Lambert
authors.forename: S
authors.initials: S
authors.lastname: Benhayoun
authors.forename: C
authors.initials: C
authors.lastname: Adjalla
authors.forename: M A
authors.initials: MA
authors.lastname: Gelot
authors.forename: P
authors.initials: P
authors.lastname: Renkes
authors.forename: F
authors.initials: F
authors.lastname: Felden
authors.forename: P
authors.initials: P
authors.lastname: Gerard
authors.forename: F
authors.initials: F
authors.lastname: Belleville
authors.forename: P
authors.initials: P
authors.lastname: Gaucher
authors.forename: J L
authors.initials: JL
authors.lastname: Guéant
authors.forename: J P
authors.initials: JP
authors.lastname: Nicolas
mesh_terms: D000328:Adult; D003424:Crohn Disease / Q000097:blood*; D004912:Erythrocytes / Q000737:chemistry; D005260:Female; D005492:Folic Acid / Q000097:blood; D006710:Homocysteine / Q000097:blood; D006801:Humans; D008297:Male; D008764:Methylmalonic Acid / Q000097:blood; D014155:Transcobalamins / Q000032:analysis; D014805:Vitamin B 12 / Q000031:analogs & derivatives / Q000097:blood*
chemical_list: D014155:Transcobalamins; D006710:Homocysteine; D008764:Methylmalonic Acid; D005492:Folic Acid; D014805:Vitamin B 12