Metastatic right lower abdominal pain is most commonly associated with an attack of acute appendicitis. Early onset of abdominal pain in acute appendicitis is not in the right lower abdomen at the McDonald’s point, but first around or above the belly button in the upper abdomen, with paroxysmal or persistent abdominal pain, sometimes accompanied by nausea, vomiting or diarrhea. Some patients may have fever, and after a few hours or half a day or a day, the pain is gradually confined to the right abdomen with pressure pain at the point of McDonald’s, and may be accompanied by rebound pain. The diagnosis of acute appendicitis can be confirmed by the specific clinical symptoms, together with routine blood tests and local ultrasound.