DefinitionA fistula is an abnormal connection between an organ, vessel, or intestine and another structure. Fistulas are usually the result of injury or surgery. It can also result from infection or inflammation.Inflammatory bowel disease, such as ulcerative colitis or Crohn's disease, is an example of a disease that leads to fistulas between one loop of intestine and another. Injury can lead to fistulas between arteries and veins.InformationFistulas may occur in many parts of the body. Some of these are:Arteriovenous (between an artery and vein)Biliary (created during gallbladder surgery, connecting bile ducts to the surface of the skin)Cervical (either an abnormal opening into the cervix or in the neck)Craniosinus (between the space inside the skull and a nasal sinus)Enterovaginal (betwe