1, acute appendicitis (1) abdominal pain typical of acute appendicitis initially have pain in the upper middle abdomen or around the umbilicus, after a few hours the abdominal pain is shifted and fixed in the right lower abdomen. When the inflammation spreads to the plasma membrane layer and wall peritoneum, the pain is fixed in the right lower abdomen, and the original pain in the upper middle abdomen or around the umbilicus is reduced or disappears. Therefore, the absence of a typical history of metastatic right lower abdominal pain does not exclude acute appendicitis. Simple appendicitis often presents with paroxysmal or persistent distension and dull pain, and persistent severe pain is often indicative of septic or gangrenous appendicitis. Persistent severe pain extending to the middle and lower abdomen or both sides of the lower abdomen is often a sign of gangrenous perforation of the appendix. (2) Gastrointestinal symptoms of simple appendicitis are not prominent. In the early stage, there may be nausea and vomiting due to reflex gastric cramps. In pelvic appendicitis or gangrenous perforation of the appendix, there may be increased frequency of defecation. (3) Fever is usually only low, without chills, and septic appendicitis usually does not exceed 38°C. High fever is usually seen in cases of gangrenous appendix, perforation or peritonitis. (4) Pressure pain and rebound pain abdominal pressure pain is the manifestation of inflammatory stimulation of the wall peritoneum. The appendiceal pressure point is usually located at the McKenicke’s point, which is the junction of the middle and outer 1/3 of the line between the right anterior superior iliac spine and the umbilicus. Rebound pain is also known as Blumberg’s sign. In patients with obesity or posterior appendicitis of the appendix, the pressure pain may be mild, but there is significant rebound pain. (5) Tension of the abdominal muscles is present when the appendix is septic, and is particularly pronounced in gangrenous perforation complicated by peritonitis. However, in elderly or obese patients with weaker abdominal muscles, the contralateral abdominal muscles must be examined for comparison. (6) Skin sensory hypersensitivity in the early stage, especially in the appendiceal cavity with obstruction, can appear in the right lower abdomen skin sensory hypersensitivity phenomenon, the scope is equivalent to the 10th to 12th thoracic medullary segment innervation area, located in the highest point of the right iliac crest, the right pubic crest and umbilicus constitute the triangle, also known as Sherren’s triangle, it does not change depending on the location of the appendix, such as appendiceal gangrene perforation in this triangle of skin sensory hypersensitivity phenomenon The skin sensory allergy in this triangle disappears if the appendix is gangrenous and perforated. 2, chronic appendicitis (1) abdominal pain right lower abdominal pain, characterized by intermittent hidden pain or swelling, sometimes heavy, sometimes light, the location is relatively fixed. Most patients have abdominal pain after a full meal, exercise, exertion, cold and prolonged standing. (2) Gastrointestinal reactions Patients often have indigestion and decreased appetite of varying severity. Longer duration of the disease may show wasting and weight loss. There is usually no nausea and vomiting, and no abdominal distension, but older patients may be accompanied by constipation. (3) Abdominal pressure pain is the only sign, mainly located in the right lower abdomen, generally small in extent and constant in position, and can only appear when heavy pressure is applied. There is no muscle tension and rebound pain, and there is usually no abdominal mass. (4)The signs are positive for various specific pressure points such as McKay’s point, Lang’s point and lumbar major muscle sign and Roche’s sign.