Paris Classification of Pediatric Crohn’s Disease

A recent study described the phenotypic results of a prospective, web-based registry of new-onset pediatric inflammatory bowel disease (IBD) in 17 European countries and Israel (Inflamm Bowel Dis 2013; 19: 378-85).

The EUROKIDS Registry included 582 pediatric Crohn’s Disease (CD) patients classified according to Paris classification:

  • 16% with L1 involvement of the terminal ileum only
  • 27% with L2 colonic involvement only (more common in younger children)
  • 53% with L3 involvement of the ileum and colon
  • 4% with L4 isolated upper GI disease.  Upper tract disease can be further subdivided into L4A esophagogastric disease and L4B jejunal/proximal ileal disease.
  • *Upper GI disease can coexist with L1, L2 or L3.  In this study, 34 (6%) had esophageal involvement, 102 (18%) had gastric involvement, and 100 (17%) had duodenal involvement.
  • In this study, 165 of the 507 patients did not undergo small bowel imaging. Of those who did, 64% had small bowel follow-through, 38% had MRI, 6% CT, and 5% video capsule.

Other findings:

  • Perianal disease (e.g.. fistula or abscess) noted in 9% at diagnosis.
  • Granulomas were found in 43% of patients who had biopsies from at least 10 segments of the GI tract
  • 82% of CD patients had nonstricturing, nonpenetrating disease (B1), 12% had stricturing disease (B2) and 5% had penetrating disease (B3).  2% had both stricturing and penetrating disease.
  • Extraintestinal manifestations were seen in 20% of the study population.
  • The authors estimated that the diagnostic yield of upper endoscopy  in the workup for pediatric IBD was  7.5% and for intubation of the ileum/ileoscopy 13%.

Study limitations included a selection bias of centers and pediatric gastroenterologists with a special interest in IBD.  Also, in this registry, older adolescents are underrepresented. In about one-third of the centers, patients older than 15 years are seen primarily by adult gastroenterologists.