title: Disease phenotype at diagnosis in pediatric Crohn's disease: 5-year analyses of the EUROKIDS Registry.
abstract: BACKGROUND
  It has been speculated that pediatric Crohn's disease (CD) is a distinct disease entity, with probably different disease subtypes. We therefore aimed to accurately phenotype newly diagnosed pediatric CD by using the pediatric modification of the Montreal classification, the Paris classification.
  
  
  METHODS
  Information was collected from the EUROKIDS registry, a prospective, web-based registry of new-onset pediatric IBD patients in 17 European countries and Israel. When a complete diagnostic workup was performed (ileocolonoscopy, upper gastrointestinal [GI] endoscopy, small bowel imaging), CD patients were evaluated for ileocolonic disease extent, esophagogastroduodenal involvement, and jejunal/proximal ileal involvement. Disease behavior and the occurrence of granulomas were also analyzed.
  
  
  RESULTS
  In all, 582 pediatric CD patients could be classified according to the Paris classification. Isolated terminal ileal disease (± limited cecal disease) was seen at presentation in 16%, isolated colonic disease in 27%, ileocolonic disease in 53%, and isolated upper GI disease in 4% of patients. In total, 30% had esophagogastroduodenal involvement and 24% jejunal/proximal ileal disease. Patients with L2 disease were less likely to have esophagogastroduodenal involvement or stricturing disease than patients with L1 or L3 disease. Terminal ileal disease and stricturing disease behavior were more common in children diagnosed after 10 years of age than in younger patients. Granulomas were identified in 43% of patients.
  
  
  CONCLUSIONS
  Accurate phenotyping is essential in pediatric CD, as this affects the management of individual patients. Disease phenotypes differ according to age at disease onset. The Paris classification is a useful tool to capture the variety of phenotypic characteristics of pediatric CD.
authors.affiliation: Department of Pediatric Gastroenterology, Erasmus MC-Sophia Children's Hospital, Rotterdam, The Netherlands.
authors.forename: Charlotte I
authors.initials: CI
authors.lastname: de Bie
authors.forename: Anders
authors.initials: A
authors.lastname: Paerregaard
authors.forename: Sanja
authors.initials: S
authors.lastname: Kolacek
authors.forename: Frank M
authors.initials: FM
authors.lastname: Ruemmele
authors.forename: Sibylle
authors.initials: S
authors.lastname: Koletzko
authors.forename: John M E
authors.initials: JM
authors.lastname: Fell
authors.forename: Johanna C
authors.initials: JC
authors.lastname: Escher
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D002432:Cecum / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D003106:Colon / Q000473:pathology*; D003424:Crohn Disease / Q000145:classification / Q000150:complications / Q000175:diagnosis*; D016099:Endoscopy, Gastrointestinal; D005060:Europe; D005260:Female; D006099:Granuloma / Q000209:etiology; D006801:Humans; D007082:Ileum / Q000473:pathology*; D007223:Infant; D007231:Infant, Newborn; D007557:Israel; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D010641:Phenotype; D011446:Prospective Studies; D012042:Registries; D014057:Tomography, X-Ray Computed; D041742:Upper Gastrointestinal Tract / Q000473:pathology*