In the group with CD, the percent of IgA- and IgG-coated bacteria were positively, significantly, and directly correlated with markers of inflammation, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) (p < 0.0001 for both), and severity of disease as measured by Crohn’s disease activity index (CDAI) (p < 0.0001 for both immunoglobulins), and Simple Endoscopic Score in Crohn’s disease (SES-CD) (p < 0.0001 for both immunoglobulins). Here, CRP is linked to Crohn disease.