Appendicitis is a common pediatric emergency abdomen, with incidence gradually increasing with age, peaking at 6-12 yrs. Appendicitis under 3 yrs of age, especially within 1 yr of age, develops rapidly and has a high rate of perforation. Zhou Tao, Department of Liver Surgery, Shanghai Renji Hospital Etiology: blockage of appendiceal cavity and pathogenic bacterial infection Classification: Simple appendicitis (can be interpreted as mild) Suppurative appendicitis (can be interpreted as moderate) Gangrenous appendicitis (can be interpreted as severe) Common manifestations: Generally, the younger the age, the less typical the clinical manifestations and the faster the disease progresses. 1. Abdominal pain. The most common and earliest appearing symptom. It mostly starts from the umbilicus, from mild to severe, and gradually shifts to the right lower abdomen after a few hours. Most children prefer to lie in the right hip flexion position; 2, nausea, vomiting. The vomit is mostly food that has been ingested; 3. Fever. The temperature is around 38°C. Most of them have abdominal pain followed by fever, which gradually increases as the condition worsens; 4. Increased defecation and diarrhea. Treatment: Pediatric appendicitis, regardless of the type, should be treated with early surgery. The choice of surgical methods: 1 conventional appendectomy; 2 conventional laparoscopic appendectomy; 3 single-port laparoscopic appendectomy. The details will be explained to you in detail by the surgeon before surgery. Non-surgical treatment: fasting + antibiotics + fluid replacement. Antibiotic selection (in general, choose second-generation cephalosporin + ornidazole; if the infection is serious, the level of antibiotics can be adjusted according to the specific situation).