Serum anti-glycan antibodies predict complicated Crohn's disease behavior: a cohort study.

BACKGROUND: A high proportion of patients with Crohn's disease (CD) over time develop complications like fistulae and strictures, requiring surgery. We tested a panel of antiglycan antibodies for predicting the occurrence of complications and CD-related surgery in an adult patient cohort.
METHODS: Serum samples of 149 CD patients of the German inflammatory bowel disease (IBD) network were tested for the presence of anti-laminarin IgA (Anti-L), anti-chitin IgA (Anti-C), anti-chitobioside IgA (ACCA), anti-laminaribioside IgG (ALCA), anti-mannobioside IgG (AMCA), and anti-Saccaromyces cerevisiae IgG (gASCA) carbohydrate antibodies by enzyme-linked immunosorbent assay (ELISA) (IBDX(R) panel, Glycominds, Lod, Israel) in a blinded fashion. Clinical data were available on occurrence of complicated disease or CD-related surgery as well as disease activity, onset, and location.
RESULTS: The median follow-up of the patients without any previous complication or surgery at time of sample procurement was 53.7 months. Overall, 26.3% developed a complication and 17.1% underwent CD-related surgery, respectively. Positivity for gASCA, AMCA, ACCA, and Anti-L alone or an increasing frequency of positive serum antibodies independently predicted a faster progression toward a more severe disease course. Once a complication or surgery had occurred only positivity for Anti-L or more than 3 markers out of the whole panel indicated progression to an additional surgery or complication. The antibody status of most patients remained stable over time.
CONCLUSIONS: This is the first study showing the clinical value of serum antiglycan antibodies for prediction of a more complicated disease course in adult patients with CD.