When acute pancreatitis has a typical medical history, symptoms and signs, combined with blood and urine amylase determination (>256 Win units or >500 So units), and imaging (X-ray, ultrasound and CT), the diagnosis is not difficult. However, when there is no typical clinical manifestation, it is not easy to diagnose. Therefore, whenever you encounter acute abdominal disease, you should think about the possibility of this disease and make dynamic observation of its clinical signs and various laboratory test results in order to supplement and improve the diagnosis. If necessary, amylase determination of the abdominal puncture fluid can be of great help in the diagnosis. Sometimes attention should also be paid to the primary disease causing the disease to prevent it from being masked. Thus, it should be carefully analyzed to prevent misdiagnosis. It should also be distinguished from acute cholecystitis, cholelithiasis, ulcerative perforation, acute intestinal obstruction and coronary artery disease in the diagnosis, which can be differentiated by comparing their respective characteristics with this disease. The diagnosis of pancreatitis by amylase is still a good and simple means. As pancreatic enzymes in the pancreatic duct reflux into the blood or exudate reabsorption into the blood, the blood and urine amylase is elevated in acute pancreatitis. The normal value of blood amylase is <256 units of WEN and <500 units of SU. Acute pancreatitis (mild) is elevated 6 to 12 hours after the onset, and gradually return to normal in 48 to 72 hours, urinary amylase is elevated about 12 to 24 hours after the onset, to last 3 to 5 days. However, the time of elevation in acute heavy pancreatitis is earlier. Clinical changes in amylase values should be analyzed comprehensively, and then combined with other clinical symptoms to make a correct judgment. Normal amylase value: the disease has healed and can return to normal, when the general condition is good and there are no abdominal signs. In acute hemorrhagic necrotizing pancreatitis, the condition of heavy dukes, at the initial examination or during treatment, amylase is not elevated, which can indicate progressive aggravation and further deterioration of the disease. The pancreatic alveoli are unable to secrete amylase due to massive necrosis and collapse - "depletion". This phenomenon occurs in acute hemorrhagic necrotizing pancreatitis and should be given great attention. Elevated amylase: Sometimes patients present with abdominal pain and elevated amylase, but the clinical signs and symptoms are not pancreatitis. Serum amylase tests are often non-specific, and acute pancreatitis can have varying degrees of elevation depending on the extent of the lesion. The amylase may also be elevated in some common acute abdominal conditions, such as cholecystitis, cholelithiasis, biliary obstruction, intestinal obstruction, ulcerative perforation, mesenteric thrombosis, and after morphine use. In cholelithiasis, amylase may be elevated due to the stimulation of the sphincter of Oddi during stone evacuation, causing spasm and a transient amylase elevation. In ulcer perforation (especially duodenal bulb perforation), the intestinal contents contain a large amount of pancreatic fluid, which is absorbed by the peritoneum after entering the peritoneal cavity, resulting in an elevated blood amylase value. After intestinal obstruction, the amylase is absorbed through the damaged intestinal wall by the sludge of intestinal fluid in the intestinal cavity. Therefore, the elevation of amylase must be judged clinically, and the diagnosis of pancreatitis must not be made because of elevated amylase. Severe pancreatitis is often accompanied by a large amount of inflammatory ascites in the abdominal cavity, a laparotomy should be done to determine amylase, and the ascites extracted by the puncture is mostly a bloody, cloudy fluid. Amylase levels can be very high. Amylase-creatinine renal contouring ratio (ACCR): The normal ratio of ACCR is 3.8 to 5.3%, if the ratio is >5 to 6% it indicates acute pancreatitis. It has been found that the ACCR can also be elevated in diseases other than acute pancreatitis (such as chronic renal failure, diabetic acidosis, burns, and severe liver failure), so it is specific only when these diseases are excluded. The amylase-creatinine renal clearance ratio is calculated as: (urinary amylase/serum amylase) × (serum creatinine/urinary creatinine) × 100.