The main clinical manifestations of peritonitis, in the early stage, are symptoms of peritoneal irritation, such as abdominal pain, abdominal muscle tension and rebound pain. In the later stage, due to infection and toxin absorption, the main manifestation is the symptoms of systemic infection poisoning. 1, abdominal pain This is the most important symptom of peritonitis. However, it is usually very intense, unbearable and persistent. Deep breathing, coughing, turning the body can intensify the pain. Therefore, the patient can not change position, pain more from the primary focus, the spread of inflammation spread and the whole abdomen, but still the primary lesion site is more significant. 2, nausea, vomiting This is a common symptom of early appearance. At the beginning, the peritoneum is stimulated to cause reflex nausea and vomiting, and the vomit is the stomach contents. When paralytic intestinal obstruction occurs later, the vomit becomes yellow-green or even brown fecal-like intestinal contents. 3, fever Sudden onset of peritonitis can start with a normal body temperature, and then gradually increase. In elderly and debilitated patients, the temperature does not necessarily increase with the exacerbation of the disease. The pulse rate usually increases with the increase in temperature. 4. Infection poisoning When peritonitis enters a severe stage, systemic toxicity such as high fever, dry mouth, rapid pulse, and shallow breathing often appear. In the later stage, due to the absorption of a large amount of toxins, the patient is in indifferent expression, emaciated face, sunken eye sockets, cyanosis of the lips, cold limbs, yellow and dry tongue, dry skin, shortness of breath, weak pulse, sharp rise or fall in body temperature, drop in blood pressure shock, and acidosis. 5, abdominal signs manifested as abdominal breathing is weakened or disappeared, and accompanied by obvious abdominal distension. Pressure pain, rebound pain is the main sign of peritonitis, always present, usually throughout the abdomen and most significant at the site of the primary lesion.