Vitamin B12 deficiency in inflammatory bowel disease: a prospective observational pilot study.

TitleVitamin B12 deficiency in inflammatory bowel disease: a prospective observational pilot study.
Publication TypeJournal Article
Year of Publication2017
AuthorsBattat R, Kopylov U, Byer J, Sewitch MJ, Rahme E, Nedjar H, Zelikovic E, Dionne S, Bessissow T, Afif W, Waters PJ, Seidman E, Bitton A
JournalEur J Gastroenterol Hepatol
Date Published2017 Dec
KeywordsCodon, Nonsense, Colitis, Ulcerative, Crohn Disease, Female, Fucosyltransferases, Humans, Male, Methylmalonic Acid, Middle Aged, Pilot Projects, Prospective Studies, Risk Factors, Severity of Illness Index, Vitamin B 12, Vitamin B 12 Deficiency

BACKGROUND AND AIM: Diagnostic and management guidelines for vitamin B12 (cobalamin, Cbl) deficiency in inflammatory bowel disease (IBD) are lacking. True deficiency is defined as Cbl concentrations below reference range combined with elevated methylmalonic acid (MMA) concentrations. Studies analyzing Cbl status in IBD use only Cbl concentrations without confirmatory MMA. This study aims to determine the proportion of IBD patients with Cbl concentrations below reference range and their predisposing clinical and genetic characteristics. We then compared this to the proportion with true deficiency.

PATIENTS AND METHODS: In a prospective observational pilot study of adult IBD outpatients, Cbl concentrations, MMA levels, and fucosyltransferase 2 mutations were measured at clinic visits.

RESULTS: A total of 66 Crohn's disease (CD) and 30 ulcerative colitis (UC) patients were recruited. Mean Cbl concentrations (pmol/l) in CD (253.7) were not significantly lower than UC (320.5, P=0.24). Serum Cbl below reference range (<148) was observed in 7.6 and 10% of CD and UC patients, respectively (P=0.70). True deficiency in CD and UC was 3 and 3.3%, respectively (P=1.0). Patients with ileal resections more than 30 cm had lower mean Cbl concentrations (177, P=0.02) and a trend toward higher proportions with Cbl levels below reference range (40%, P=0.06), but not increased deficiency rates (0%, P=1.0). Disease location, severity, and fucosyltransferase 2 mutations were not associated with altered Cbl status.

CONCLUSION: True Cbl deficiency was rare in IBD patients in this study. A disparity in Cbl status exists when confirmatory MMA levels are used compared with Cbl concentrations alone. Asymptomatic IBD patients with low serum Cbl require confirmatory tests to guide management and avoid unnecessary treatment.

Alternate JournalEur J Gastroenterol Hepatol
PubMed ID28953003