AAST grade	Description	Management	References
I	Acute edematous pancreatitis	Diagnosis by serum markers. Supportive management and enteral nutrition as tolerated. Cholecystectomy at index admission if gallstones present. Antibiotics not indicated. If concomitant cholangitis is present early ERCP should be performed. For choledocholithiasis, without cholangitis ERCP can be delayed for 72 hours.	1 2 3 4
II	Pancreatic phlegmon or peripancreatic fluid collection or hemorrhage	Same as grade I plus CT scanning at least 72 hours after symptom onset.	1 2 3 4
III	Sterile pancreatic necrosis	Same as grade II disease Management in a monitored setting (intensive care unit) Parenteral nutrition for those failing enteral nutrition.	1 2 3 4
IV	Infected pancreatic necrosis or abscess	Same as grade III disease. Antibiotics for suspected infection. Consider percutaneous sampling or drainage Necrosectomy delayed at least 14 days after symptom onset Necrosectomy technique guided by local expertise. Open necrosectomy should be avoided	1 2 3 4 5
V	Extrapancreatic extension of pancreatic necrosis involving adjacent organs, such as colonic necrosis	Same as grade IV disease.	1 2 3 4 5