Aim of the present study is to compare a stapled, functional end-to-end, ileo-colic anastomosis with removal of the mesentery vs the manual, functional end-to-end, ileo-colic Kono-S anastomosis with mesentery preservation, in terms of peri-operative safety, and efficacy in preventing endoscopic recurrence after ileocolic resection for Crohn Disease. Patients presenting with ileocolic primary Crohn disease either not suitable for medical treatment or with contraindications for therapy i.e: occlusion, abscess, contraindications to the use of biologics

Patients who meet inclusion criteria will be randomized between two surgical procedures:

The excision of the mesentery (group A) and ileocolic anastomosis and the Kono-S anastomosis (group B) after ileocolic or ileo-cecal resection. The operation could be performed with open or laparoscopic approach.

Excision of the mesentery:

the mesentery is fully dissected and excised to the limit of macroscopic "fat wrapping", where mesenteric fat is inflamed and extends beyond its normal anatomical distribution over the surface of the contiguous intestine. The anastomosis between colon and ileum is than performed mechanically end to end.

Kono-S anastomosis:

the mesentery is not removed but cutted close to the bowel. The bowel is then divided transversely by placing a linear stapler perpendicular to the intestinal lumen and the mesentery. The corners of the two staple lines are reinforced and the two stumps are approximated using 5-7 sutures to create the column.

If the caliber of the two intestinal segments differs significantly, the sutures should be spaced to evenly distribute the surplus tissue of the larger segment, in order to achieve good approximation and stable support for the anastomosis. To create the anastomosis, an antimesenteric longitudinal enterotomy (or colostomy) is performed on each stump to allow a transverse lumen of 7 cm in diameter for the small bowel or closer to 8 cm for the colon. In this way the supporting column is located immediately behind the posterior wall of the anastomosis providing a rigid and stable support to prevent mechanical deformation and functional constriction of the lumen of the anastomosis.

Inclusion Criteria:

• • Patients > 18 years

  • Histological diagnosis of Crohn's Disease
  • Patient's ability to read and understand the documentation concerning the study and the Informed consent
  • Ileocolic disease requiring resection

Exclusion Criteria:

• Older than 70

  • Recurrent disease, previous surgery for CD
  • Gastroenterologists or patients not willing to maintain a drug washout for six months
  • Emergency surgery

We surely consider to share individual participant data (IPD) during the study and often it is necessary. At the moment of the study design we dis not fix a precise plane of sharing data. During the follow up clinical and endoscopic examinations of patients have been scheduled in order to avoid missing data or drop-out from the study. The first role of all investigators in this study was to follow each patients operated on and enrolled in this specific study