A gastrointestinal fistula (GIF) is an abnormal opening in your digestive tract that allows gastric fluids to seep through the lining of your stomach or intestines. This can result in infection when it leaks into your skin or other organs.
GIF most commonly occurs after intra-abdominal surgery, which is surgery inside your abdomen. People with chronic digestive problems also have a high risk of developing a fistula.