To analyze the clinical characteristics and prognosis in different subtypes of upper gastrointestinal Crohn's disease (CD) patients.

CD patients treated at Shanghai Ruijin Hospital from 2017 to 2021 were enrolled. They were divided into the upper gastrointestinal tract involvement (UGI+) group and non-upper gastrointestinal tract involvement (UGI-) group based on endoscopic and pathological findings. The upper gastrointestinal tract involvement rate of CD patients, the endoscopic characteristics and severity of UGI+ group were analyzed. Kaplan Meier method was used to survival curve, and the differences of 3-year continuous operation-free rate and complication free rate between UGI+ and UGI- group were analyzed. Patients in the UGI+ group were further divided according to whether duodenal bulb was involved, and the difference of prognosis among different subtypes was compared.

A total of 76 patients were included in this study, among which 46 cases had 68 positive endoscopic findings. Endoscopic features were diverse and the bamboo joint-like appearance of the gastric fundus had the highest incidence (20.6%), followed by duodenal ulcers (17.6%) and protruding lesions of the duodenal bulb (14.7%). After follow-up, there was no significant difference between the UGI+ group and the UGI- group in the 3-year continuous operation-free rate (P>0.05). Further subgroup analysis showed that the 3-year event-free rate in the UGI- group, CD upper digestive tract involving non-duodenal bulb group (UGI+DB- group) and CD upper digestive tract involving duodenal bulb group (UGI+DB+ group) were 88.9%, 87.9% and 68.0%, respectively. The 3-year event-free rate of the UGI+DB+ group was significantly lower than that in the UGI- group and UGI+DB- group (P<0.05).

Upper gastrointestinal involvement is not uncommon in newly diagnosed CD patients, and its endoscopic manifestations are varied. Endoscopy should be recommended to newly diagnosed CD patients regardless of asymptomatic gastrointestinal symptoms. UGI+ patients with duodenal bulb involvement have significantly higher rates of surgery or complications. Therefore, active treatment should be promptly provided to this subgroup of patients to improve their prognosis.