P431 Long-term efficacy of maintenance therapy with thiopurines in Crohn's disease

and reoperation between two groups using the Kaplan Meier method and a log-rank test. Results: Of a total 721 patients, 443 (61.4%) were the second group. Although the cumulative probabilities of immunosuppressant (P< 0.001) and IFX use (P< 0.001) after diagnosis were significantly higher in the second group, there were no significant differences in cumulative probabilities of operation (P= 0.905) and reoperation (P= 0.418) between two groups. Conclusions: The early use of IFX did not reduce CD-related surgery requirements in Korean patient with CD. Our results suggest that the early use of IFX may have little impact in the clinical outcome of Korean CD in the setting of a conventional step-up algorithm.