CRP and inflammatory bowel disease: The ability to detect ATI in the presence of the IFX is important, as it was shown that IBD patients with both good IFX trough levels (⩾3 μg/ml) and ATI+ levels have significantly higher levels of C-reactive protein and less mucosal healing during treatment,7,39 which indicates a reduced control of inflammation mediated by these antibodies even when drug levels are adequate.