Acute Pancreatitis 1

Question

Vignette: A 45-year-old woman presents to the emergency department with complaints of severe abdominal pain, nausea, and vomiting. She states that the abdominal pain started 6 hours ago and has progressively worsened. The patient also reports a history of similar episodes, although they were less severe. Her medical history is significant for chronic alcohol abuse. Physical examination reveals a distended abdomen with diffuse tenderness and involuntary guarding. Laboratory findings show an elevated serum amylase and lipase. The patient is admitted with a diagnosis of acute pancreatitis.

Question: Which of the following pathophysiologic mechanisms is most likely responsible for the patient's presentation?

Choices

A) Auto-digestion of the pancreatic tissue by trypsin

B) Gallstone obstruction of the common bile duct

C) Hepatocellular damage leading to decreased bile production

D) Gastric acid reflux into the pancreatic duct

E) Immune-mediated destruction of the pancreatic acinar cells

Answer

A) Auto-digestion of the pancreatic tissue by trypsin

Explanation

This patient's presentation of severe abdominal pain, nausea, vomiting, and a history of alcohol abuse, along with laboratory findings of elevated serum amylase and lipase, are consistent with acute pancreatitis. Acute pancreatitis is most commonly caused by gallstones and alcohol abuse. In both conditions, premature activation of pancreatic enzymes occurs within the pancreatic acinar cells, leading to auto-digestion of the pancreatic tissue. One of the key enzymes in this process is trypsin, which is normally produced as the inactive proenzyme trypsinogen by the pancreas and later activated in the duodenum. In acute pancreatitis, however, trypsinogen is activated within the pancreas, leading to trypsin-mediated auto-digestion and inflammation. Therefore, the most likely pathophysiologic mechanism in this patient is auto-digestion of the pancreatic tissue by trypsin (Choice A).