AI-Powered Research

In order to be eligible to participate in the *Crohn-fistula group* of this
study, a subject must meet all of the following criteria:
- Patients with perianal fistulas who will have surgery for their perianal
fistula including scraping of the fistula.
- Patients with confirmed Crohn*s disease (clinical and endoscopic).
In order to be eligible to participate in the *non-Crohn-fistula group* of this
study, a subject must meet all of the following criteria:
- Patients with perianal fistulas who will have surgery for their perianal
fistula including scraping of the fistula.
- Patients with no clinical suspicion for IBD (based on the fecal calprotectin
(FCP)) or no signs of inflammation on endoscopy.

Exclusion Criteria

A potential subject who meets any of the following criteria will be excluded
from participation in this study:
- In the *non-CD-fistula group* perianal fistulas cannot be the result of
pelvic malignancy or radiation therapy or another known medical condition in
the pelvic region.

Study & Design

Study Type: Observational invasive

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
<p>Differences in immune cell populations analysis between fistula tracts from<br /><br>patients with and without Crohn*s disease.</p><br>

Secondary Outcome Measures

Name	Time	Method
<p>Differences in immune cell population in rectum biopsies from patients with and<br /><br>without Crohns disease.<br /><br>Correlation of immune cell populations in the fistula tracts with immune cells<br /><br>in peripheral blood and rectum biopsies.<br /><br>Differences in microbiota between fistula tracts from patients with and without<br /><br>Crohns disease.<br /><br>Differences in the microbiota of the gut and the fistula tract.<br /><br>Differences in fibroblast expression patterns between fistula tracts from<br /><br>patients with and without Crohn's disease<br /><br>Differences in the fibroblast expression patterns of fistula tract and the<br /><br>rectum biopsies </p><br>