The patient is a 46-year-old male who presented to the clinic with abdominal distension with nausea, vomiting and diarrhea for 2 days. The patient reported that he had abdominal distension with nausea and vomiting, mainly in the right upper abdomen, and diarrhea (2~4 times) without any cause 2 days ago, and his body temperature was measured at 36.7 degrees Celsius. The abdominal distension and pain were not related to breathing and posture, the respiratory sounds of both lungs were symmetrically audible, no dry or wet Laodicean lung sounds were audible at 80 beats/min, the rhythm was uniform, no pathological murmur was audible in each valve area; the abdomen was elevated, the pain on compression in the middle and upper abdomen was obvious (pain on compression in the middle part of the abdomen was band-like), no rebound pain. The abdominal skin did not show subcutaneous bleeding spots and petechiae, the liver and spleen were not found under the rib cage, and the percussion pain in both kidney areas was not obvious. Past history: chronic superficial gastritis for more than 15 years, gallbladder removal 5 years ago due to gallbladder stones, postoperative general condition is good; 2 years ago due to acute appendicitis outside the hospital appendectomy; combined with the patient’s past history and current signs temporarily given anti-inflammatory, antispasmodic and protection of the gastrointestinal tract and other symptomatic treatment and wait for the relevant test results. Emergency examination showed: blood routine: leukocytes 14.3*109/L, N 91%, no abnormal blood amylase, slightly abnormal electrolytes, blood glucose 12 mmol/L, blood lipids 15 mmol/L; emergency diagnosis: 1, acute gastroenteritis; 2, acute pancreatitis (abnormal blood glucose, blood lipids) after symptomatic treatment, the condition did not improve significantly, the upper and middle abdomen is still elevated, pressure pain is obvious, no rebound pain, body temperature 37.4 degrees Celsius, accompanied by chills, blood and urine amylase re-examination were normal, abdominal CT suggested: fatty liver sound image, pancreatic swelling; diagnosed by comprehensive surgical consultation: acute necrotizing pancreatitis. The reason for the misdiagnosis of the above case; (1) the patient had a long onset with upper and middle abdominal distension and pain with nausea, vomiting and diarrhea as the first symptoms, no fever, no rebound pain in the abdomen, no bleeding spots or petechiae on the skin, lack of typical manifestations of acute necrotizing pancreatitis; (2) the patient’s past history and too much attention to blood amylase and electrolyte test results while ignoring changes in blood glucose and blood lipids easily mislead the physician’s thinking direction. What about in clinical practice? In the author’s opinion, it is important to dynamically observe the evolution of the patient’s condition. The patient could still eat and drink 48 hours after the onset of symptoms and the exacerbation was not obvious. Usually, due to the anatomical relationship of the pancreas, acute necrotizing pancreatitis causes significant pain and rapid progression of the disease, but the patient’s two blood biochemical results do not match the signs and radiological examinations shown, and the reason for this performance is not unrelated to the patient’s diarrhea. Because of normal defecation after the onset of the disease, the gastrointestinal tract is in a relatively active state and the oddis sphincter remains relatively dilated, which will eliminate part of the amylase from the intestine, reducing the damage to the pancreatic gland itself and slowing down the development of the disease. However, for a diagnosed disease in the emergency room, if the treatment effect is poor or even aggravated, we should immediately ask the relevant departments to consult and seek the patient’s consent before decisively arranging further examinations to clarify the diagnosis and, if necessary, to perform emergency surgery. Surgical treatment. Just as patients with substantial abdominal organ lesions and myocardial infarction can present with abdominal pain.