Pancreas

Question 1

What is the pathogenesis for acute pancreatitis?

Answer 1

Zymogen granules fuse with lysosomes –> lysosomal protease activates trypsinogen to trypsin –> pancreatic secretory trypsin inhibitor overwhelmed –> trypsin activates digestive enzymes in the pancreas –> autodigestion –> inflammation

Question 2

What are the initiating events of an acute pancreatitis?

Answer 2

Diet (high in fat)

Trauma

Ischemia

Drug use

Metabolic (diabetes)

Infection

Toxin

Question 3

Pathogenesis of actue pancreatitis:

Intra-pancreatic activation of typsin –> acinar cell damage with activation of additional digestive enzymes –>

1. Kallikrein-kinin activation –> ?
2. Chymotrypsin activation –> ?
3. Elastase activation –> ?
4. Lipase activation –> ?
5. Phospholipase A2 activation –> ?

Answer 3

1. Kallikrein-kinin –> inflammation & edema
2. Chymotrypsin –> edema, vascular damage
3. Elastase –> vascular damage, hemrrohage
4. Lipase –> fat necrosis
5. Phospholipase A2 –> coagulation necrosis

Question 4

What are the gross lesions of an acute pancreatitis?

Answer 4

Hyperemia

Hemorrhage

Necrosis

Fibrinopurulent exudate

Peripancreatic fat necrosis

Fibrinous adhesions to adjacent structures

Question 5

Is this acute or chronic pancreatitis?

Answer 5

Acute

NOTE: hyperemia

Question 6

What is your morphologic diagnosis?

Answer 6

Acute, diffuse necrotizing and fibrinous pancreatitis

Question 7

What causes the peripancreatic fat necrosis present?

Answer 7

Release of activated enzymes into adjacent fat results in peripancreatic fat necrosis (arrows)

Question 8

Answer 8

Peripancreatic fat necrosis

Question 9

Pathogenesis of acute pancreatitis:

Initiating event –> intra-pancreatic trypsin activation –> trypsin activate additional proenzymes (like what??)

Answer 9

Phospholipase A2

Lipase

Chymotrypsin

Elastase

Question 10

What happens with repeated bouts of pancreatitis?

Answer 10

Repeated bouts of pancreatitis –> partial digestion of the pancreas –> replacement with fibrous tissue –> repeat

Chronic relapsing pancreatitis –> fibrosis & atrophy –> exocrine pancreatic insufficiency (diabetes mellitus)

Question 11

What happens with severe pancreatitis?

Answer 11

Severe disease –> systemic release of inflammatory mediators (kallikrein-kinins) and activated digestive enzymes –> shock, respiratory distess, DIC, & death