P730 Disease phenotype of Korean paediatric Crohn's disease patients at diagnosis: a multicentre retrospective comparative study with EUROKIDS
Kang B.*1, Kim J.-E.2, Kim S.3, Kim M.J.4, Lee Y.M.5, Lee J.H.6, Lee J.-H.7, Lee H.J.8, Lee Y.9, Choe Y.H.1, Choe B.-H.2
1Samsung Medical Center, Sungkyunkwan University School of Medicine, Department of Pediatrics, Seoul, South Korea 2Kyungpook National University Hospital, Kyungpook National University School of Medicine, Department of Pediatrics, Daegu, South Korea 3Severance Hospital, Yonsei University College of Medicine, Department of Pediatrics, Seoul, South Korea 4Ilsan Paik Hospital, Inje University College of Medicine, Department of Pediatrics, Goyang, South Korea 5Soonchunhyang University Bucheon Hospital, Soonchunhyang University College of Medicine, Department of Pediatrics, Bucheon, South Korea 6Korea University Ansan Hospital, Korea University School of Medicine, Department of Pediatrics, Ansan, South Korea 7Chungbuk National University Hospital, Chungbuk National University College of Medicine, Department of Pediatrics, Cheongju, South Korea 8Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Department of Pediatrics, Changwon, South Korea 9Korea University Anam Hospital, Korea University College of Medicine, Department of Pediatrics, Seoul, South Korea
There is limited data regarding the disease phenotype of paediatric Crohn's disease (CD) patients in the Asian population. We aimed to investigate the disease phenotype of Korean paediatric CD patients at diagnosis according to the Paris classification by comparison with patients from the EUROKIDS registry.
Paediatric CD patients who were newly diagnosed before 18 years-old from 9 tertiary medical centers in Korea during January 2013 to October 2016 were included in this retrospective study. Medical charts were reviewed and disease phenotype at diagnosis was classified according to the Paris classification. Regarding disease phenotype, only the patients who had conducted a complete diagnostic workup of the entire gastrointestinal (GI) tract were included. A complete workup required ileocolonoscopy, upper GI endoscopy, and small bowel imaging by at least one of the following modalities; magnetic resonance enterography, computed tomography enterography, capsule endoscopy. Comparison was performed by utilizing data from the previously published 5-year analysis of the EUROKIDS registry .
A total 230 subjects [150 males (M), 80 females (F)] were included. The median age at diagnosis was 14.7 years (range: 1.2–17.9). No significant difference was observed in M:F ratio compared with EUROKIDS (1.88:1 vs. 1.46:1, p=0.088). A complete workup was done in 213 subjects. The proportion of children <10 years (A1a) was significantly lower in Koreans (6.6% vs. 19.6%, p<0.001). Colonic disease was less prominent (9.9% vs. 27.3%, p<0.001), while upper GI involvement was more prominent in Korean children (60.1% vs. 46.2%, p<0.001). Although no significant difference was observed in luminal disease behaviour, the proportion with perianal modifiers were significantly higher in Korean patients (46.5% vs. 8.2%, p<0.001). Meanwhile, a first-degree family history of inflammatory bowel disease was significantly lower in Korean children (4.8% vs. 10.8%, p=0.005).
Korea (n=213) EUROKIDS (n=582) Diagnosis age, n (%) A1a 14 (6.6%) 114 (19.6%) $<0.001$ A1b/A2 213 (93.4%) 468 (80.4%) Lower GI tract location, n (%) L1 29 (13.6%) 95 (16.3%) $<0.001$ L2 21 (9.9%) 159 (27.3%) L3 161 (75.6%) 307 (52.8%) No involvement 2 (0.9%) 21 (3.6%) Upper GI tract location, n (%) L4a 60 (28.2%) 129 (22.1%) 0.006 L4b 45 (21.1%) 97 (16.7%) L4ab 23 (10.8%) 43 (7.4%) No involvement 85 (39.9%) 313 (53.8%) Luminal disease behaviour, n (%) B1 183 (85.9%) 477 (82%) 0.241 B2 25 (11.7%) 77 (13.2%) B3/B2B3 5 (2.4%) 28 (4.8%) Perianal modifier, n (%) 99 (46.5%) 48 (8.2%) $<0.001$
Newly diagnosed paediatric CD patients in Korea are more likely to present at an older age, with more ileocolonic and upper GI tract involvement, and perianal fistulas and/or abscesses, compared to their counterparts in Europe. An underlying genetic difference between races may play a role in the different expression of phenotypes in paediatric CD.
 Charlotte I. de Bie, (2013), Disease Phenotype at Diagnosis in Pediatric Crohn's Disease: 5-year Analyses of the EUROKIDS Registry, Inflamm Bowel Dis