Use

Antibodies to Saccharomyces cerevisiae (ASCA IgA) are found in approximately 75% of patients with Crohn’s disease, 15% of patients with ulcerative colitis, and 5% of healthy individuals. Elevated titers increase the likelihood of Crohn’s disease and are associated with more aggressive disease course. IgA antibodies predominate in mucosal inflammation characteristic of Crohn’s disease, and a subset of patients display only IgG or only IgA antibodies when both tests are available.