Poor Concordance Between Clinical Activity and Endoscopic Severity in Pediatric Crohn's Disease: Before and After Induction Therapy.

Objectives And Study: Endoscopic assessments of disease activity are important to diagnose and evaluate treatment responses in patients with Crohn's disease (CD). However, the invasiveness of endoscopy limits the application of this technique in routine examination. Thus, interest has been increasing in identifying noninvasive surrogate markers to predict endoscopic CD activity.

Methods: We retrospectively analyzed pediatric patients with new-onset CD from January 2013 to December 2018 at Zhejiang University Affiliated Children's Hospital. The disease severity was scored according to the Crohn's Disease Endoscopic Index of Severity (CDEIS). Routine blood tests were determined individually. Clinical activity was assessed based on the Pediatric Crohn's Disease Activity Index (PCDAI).

Results: A total of 91 patients with CD had undergone one or more ileocolonoscopies (n = 146), the mean CDEIS for all the pediatric patients with CD was 7.0 (95% CI 5.7-8.2), and the mean PCDAI was 20.9 (95% CI 18.3-23.5). Pearson's linear analysis of the CDEIS and PCDAI in pediatric patients with CD showed a moderate correlation (r = 0.508, P < 0.001). Weak correlations were found between the PCDAI and CDEIS at the first diagnosis (r = 0.408, P < 0.001) and after completing induction therapy (r = 0.286, P < 0.05). Routine blood tests also did not correlate well with the CDEIS.

Conclusions: This study identified weak correlations between the PCDAI and CDEIS in assessing pediatric patients with CD severity both at first diagnosis and after induction therapy. A comprehensive assessment of PCDAI, CDEIS and multiple laboratory factors should be performed at diagnosis and during the follow-up of patients with CD.