Which sign is a classic indicator of severe necrotizing pancreatitis characterized by bruising of the abdominal flanks?

The classic indicator of severe necrotizing pancreatitis characterized by bruising of the abdominal flanks is known as the Grey Turner sign. This sign is indicative of retroperitoneal hemorrhage due to the inflammation and digestion of pancreatic tissue that can lead to bleeding in the surrounding areas. In cases of severe pancreatitis, hemorrhagic pancreatitis may occur, which results in bleeding that can manifest as ecchymosis, particularly in the flanks.

Grey Turner sign specifically refers to ecchymosis located on the lateral abdominal wall, while Cullen sign pertains to periumbilical bruising, indicating intraperitoneal bleeding, which is also associated with severe pancreatitis but is not specific for the flanks.

Jaundice may be present in cases related to biliary obstruction but does not correlate with the described bruising. Ascites involves accumulation of fluid in the abdominal cavity, which is not characterized by bruising. Therefore, Grey Turner sign is the characteristic sign that reflects the severity of necrotizing pancreatitis through its distinctive bruising of the abdominal flanks.