A fistula is an abnormal connection between two organs or tissues in the body, which can cause the flow of fluid or waste material between them. Fistulas can occur in different parts of the body, including the digestive system, urinary tract, or reproductive system. Symptoms of a fistula may include drainage from an opening in the skin, pain, inflammation, or infection. Treatment for a fistula depends on the location and severity of the condition and may involve medication, surgery, or other procedures to close the abnormal connection.