Crohn's disease is a inflammatory bowel disease evolving towards the destruction of the intestinal wall resulting in stenosing or perforating complications (fistulas, abscesses).

The treatment of perforating Crohn's disease is not codified.

The old dogmas leading to surgery after failure of medical treatment have recently been overturned, particularly since the advent of anti-TNFs.

Biotherapies now have a central place, including for complicated forms. Previous studies have already looked at the usefulness of anti-TNFs in stenosing forms, or concerning ano-perineal lesions, but what about digestive fistulas.

Indeed, data are scarce, especially in paediatrics.

Inclusion Criteria:

• Minor patients (aged 3 to 18).
• Diagnosed with Crohn's disease.
• fistulizing crohn's disease

Exclusion Criteria:

- perianal crohn disease

• In consultations or hospitalized.
• CHRU and CHR of Lille, Strasbourg, Colmar, Besançon, Dijon, Reims and Nancy.
• Over the period from January 2012 to January 2022.