The study aimed to prove EEN is effective for inducing early clinical remission, mucosal healing, promoting fistula closure and reducing the size of abscess to adult CD patients. They plan to include about 50 patients and observe the effect of EEN.

Inclusion Criteria:

• >18 years old
• Patients with CD was diagnosed clinically according to previously established international criteria [9]
• The diagnosis of stricture, fistula and abdominal abscess was confirmed by ultrasound, CT enterography (CTE), and endoscopy. The bowel stricture should mainly cause by inflammation but not fibrosis.

Exclusion Criteria:

• Patients do not macth the inclusion criteria and those who refuse to taking part in the study

The detailed inclusion criteria included: 1. >18 years old 2. Patients with CD was diagnosed clinically according to previously established international criteria [9] 3. The diagnosis of stricture, fistula and abdominal abscess was confirmed by ultrasound, CT enterography (CTE), and endoscopy. The bowel stricture should mainly cause by inflammation but not fibrosis. Intolerance or failure to steroids or IFX was judged by medical history 4. The disease was in an active period.