This document discusses intestinal fistulas, including their definition, classification, etiology, clinical presentation, investigation, and management. An intestinal fistula is an abnormal connection between two epithelial surfaces, usually involving the gut and another organ. They can be classified anatomically or based on output. Causes include surgery, inflammatory bowel disease, radiation, and trauma. Patients experience drainage, fever, and abdominal issues. Management involves resuscitation, sepsis control, nutrition support, and potentially definitive surgery after 6 weeks. The goal is to allow spontaneous closure when possible or resect the involved bowel and perform anastomosis.