The purpose of this study was to look at a possible link between extraintestinal manifestations (EIM) and a more severe disease course in children with inflammatory bowel disease (pIBD). This study analyses the illness progression of pIBD patients with and without EIM in a Danish population-based cohort. The study included patients diagnosed with pIBD between 1998 and 2008 and followed them until December 31, 2014. At the end of the study, data on phenotypic, therapy, relapses, and the temporal connection between IBD relapses and EIM activity were obtained manually by reviewing patient files. 14 pIBD patients had EIM at the time of diagnosis, and 47 developed EIM throughout the follow-up period. The median follow-up period for patients with EIM was 9.6 years, while it was 8.8 years for individuals without. EIM were linked to an increased risk of biological therapy and surgery in ulcerative colitis. EIM were linked to an increased recurrence risk in Crohn’s disease. Finally, researchers discovered a favourable temporal association between IBD relapse and EIM activity.

In pIBD, the presence of EIM is linked with a more severe disease course. This should be taken into account while deciding on treatment choices, since a more aggressive treatment strategy may be required in individuals with EIM.