Crohn's disease (CD) is a nonspecific intestinal granulomatous inflammatory disease of the gastrointestinal tract with unknown etiology, accompanied by pathological changes such as ulcers, granulomas, scarring and arthritis. It is collectively referred to as inflammatory bowel disease (IBD) together with ulcerative colitis. The disease can occur throughout the digestive tract, but mainly affects the terminal ileum and adjacent colon, and the lesions are distributed segmentally. Clinically, it is characterized by abdominal pain, diarrhea, abdominal mass, intestinal fistula, and intestinal obstruction, often accompanied by extraintestinal manifestations such as fever. The course of the disease is often prolonged, with alternating attacks and remissions. Severe cases are prolonged and often have various complications and a poor prognosis.