A fistula is an abnormal tunnel that forms between two parts of the body, often developing as a result of inflammation, infection, surgery or conditions such as Crohn’s disease. ⁣ ⁣ They can cause symptoms like pain, irritation and recurrent infection. Treatment varies from person to person but may include medication, drainage procedures or surgery to remove the fistula and help the area heal properly. Thankfully I have never had one. This video gives a simple visual explanation of how a fistula