Crohn's disease and vitamin B12 metabolism.
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.
Lambert
D
D
INSERM Unit 308, Faculté de Médecine, Vandoeuvre, France.
Benhayoun
S
S
Adjalla
C
C
Gelot
M A
MA
Renkes
P
P
Felden
F
F
Gerard
P
P
Belleville
F
F
Gaucher
P
P
Guéant
J L
JL
Nicolas
J P
JP
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*
D014155:Transcobalamins; D006710:Homocysteine; D008764:Methylmalonic Acid; D005492:Folic Acid; D014805:Vitamin B 12