目的：探讨CT肠道显影（CTE）对炎症性肠病（IBD）的诊断价值。方法：对1例首诊误判为溃疡性结肠炎（UC）的克罗恩病（CD）病例的影像资料和临床资料进行全面回顾并结合文献复习，分析误判原因。结果：患者，男，57岁，符合UC第2发病高峰；临床有频繁脓血便、病变局限于结肠，符合UC常见临床表现及发病部位；首诊“肛周脓肿”入院符合CD临床特征，CTE显示病变累及肠壁全层、节段性分布，活动期肠周见大量增生血管，符合CD典型影像表现。肠镜检查两次，结论分别为“UC-重度全结肠型”“IBD-CD？”，病理取到非干酪性肉芽肿，该患者最终诊断为CD。结论：UC与CD临床及影像表现有重叠，病灶局限于结肠时，影像细节的观察及病史的采集有助于鉴别，UC是发生于黏膜及黏膜下层的病变，一般连续分布，CTE无特征性改变，结肠镜并活检是诊断UC的关键；而节段性分布、透壁性炎症、肠周“梳状征”是CD常见的CTE表现，CTE对CD诊断价值更高，当以肛周病变为首发征象时更倾向诊断为CD，两者鉴别确有困难时可以诊断为IBD类型待定。

Objective: To explore the diagnostic value of CT enterography(CTE) in inflammatory bowel disease(IBD). Methods: The imaging data and clinical data of 1 case of Crohn’s disease(CD) misdiagnosed as ulcerative colitis(UC) were analyzed retrospectively and combined with literature review. Results: A male patient of 57 years old suffered from the 2nd peak onset of UC, with frequent pus and blood stools and the lesion is limited to the colon, a common spot for UC. The first diagnosis of “perianal abscess” conforms to the clinical features of CD, and CTE showed that the lesion involved the intestinal wall of the whole layer, with segmental distribution, a large number of hyperplasia of blood vessels around bowel during the active period, which is consistent with the typical imaging of CD. Conclusions of the twice colonoscopy were “UC-severe total colonic type” and “IBD-CD?”. The patient was eventually diagnosed as a CD with pathological extraction of non-cheese granuloma. Conclusion: There are overlap in both clinical and imaging findings between UC and CD. When the lesion is confined to the colon, the observation of image details and the collection of medical history can help to identify. UC is occurring in the mucosa and submucosa, with general continuous distribution. CTE shows no characteristic changes, and colonoscopy and biopsy are the keys to the establishment of UC diagnosis. Segmental distribution, permeable wall inflammation and “Comb sign” are common CTE findings in CD. CTE is more valuable for CD diagnosis. The diagnosis of CD is preferred when perianal lesions are the first signs. The diagnosis of inflammatory bowel disease unclassified(IBDU) can be made when it is difficult to identify the two.