A 40 year old man who is alcoholic is admitted to hospital with acute pancreatitis. He is now having vomiting and feels dizzy while standing. On examination, the patient has severe epigastric tenderness in the right upper quadrant and decreased bowel sounds. Bluish discolouration is seen around the umbilicus. What is the significance of this finding?

**Core Concept**
Acute pancreatitis can lead to various complications, including local and systemic effects. One of the local effects is the development of a characteristic skin discoloration, which is a sign of severe pancreatic inflammation.

**Why the Correct Answer is Right**
The bluish discoloration around the umbilicus, also known as Cullen's sign, is a result of hemorrhagic pancreatitis. The inflammation and necrosis of pancreatic tissue lead to the release of pro-inflammatory cytokines, which cause vasodilation and increased vascular permeability. This allows erythrocytes and plasma proteins to leak into the surrounding tissues, resulting in a bluish discoloration. Cullen's sign is often associated with severe pancreatitis and has a high mortality rate.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because Cullen's sign is a local effect of pancreatitis, not a systemic manifestation like hypotension or tachycardia.

**Option B:** This option is incorrect because the presence of Cullen's sign does not indicate a specific pancreatic pathology, such as gallstones or alcohol-induced pancreatitis.

**Option C:** This option is incorrect because Cullen's sign is not a sign of bowel ischemia or necrosis, but rather a manifestation of pancreatic inflammation.

**Option D:** This option is incorrect because Cullen's sign is not a specific indicator of pancreatic abscess or pseudocyst formation.

**Clinical Pearl / High-Yield Fact**
Cullen's sign is a classic sign of severe pancreatitis and has a high mortality rate. It is essential to recognize this sign in patients with acute pancreatitis to provide prompt and aggressive treatment.

**Correct Answer:** C. Cullen's sign is a bluish discoloration around the umbilicus, indicating severe pancreatitis.

✓ Correct Answer: A. A CT of the abdomen is likely to show severe necrotizing pancreatitis.