Pathology of the Exocrine Pancreas

Question 1

Structure of the Pancreas
1. Exocrine elements:
* ___-___% of pancreas
* Consists of ______ cells forming ____
2. Endocrine elements:
* ?

Answer 1

Structure of the Pancreas
1. Exocrine elements:
* 80-85% of pancreas
* Consists of acinar cells forming acini
2. Endocrine elements:
* Islets of Langerhans

Question 2

Normal Pancreas
Two lobes:
* Left lobe
* Right lobe

Find other image

hit every quickly after death

Answer 2

Question 3

1. This is a histological image of what organ?
2. Why is most of this structure eosinoohillic?

Answer 3

Why pink? Zymogen
- if not eating for awhile, very thin –> lack of zymogen –> lacking pink color

Question 4

Label this image below.

Answer 4

When animal is eating –> zymogen granule production; depletion when not

Question 5

Below is a histological image of what organ?

Answer 5

Pancreas!

Question 6

Answer 6

Question 7

• In cats, the _________ bile duct fuses with the _________ duct before entering the _____ papilla.
  
  • Predispose cats to _____ (______, ________, _____)
• Only ____% of cats are estimated to have an accessory pancreatic duct

Answer 7

• In cats, the common bile duct fuses with the pancreatic duct before entering the major papilla.
  
  • Predispose cats to triaditis (cholangitis, pancreatitis, inflammatory bowel disease)
• Only 20% of cats are estimated to have an accessory pancreatic duct

Question 8

Cat or dog?

Answer 8

Question 9

Cat or dog?

Answer 9

find real anatomy photos of cat and dog

Question 10

Answer 10

Arrow pointing to: major duodenal papilla

GB top left, liver on top right

Question 11

Answer 11

Found in the skin as well as the pancreas in cats

Question 12

Answer 12

Looks like a fingerprint

Question 13

Function of the Pancreas?

Answer 13

1. Digestion (“pancreatic juice”)
   * Dietary lipids (lipase and phospholipase)
   * Proteins (trypsin and chymotrypsin)
   * Carbohydrates (amylase)
   * Intrinsic factor: essential for the absorption of cobalamin (vitamin B12)
2. Defenses against autodigestion
   * α1-antitrypsin: trypsin inhibitor
   - inhibits trypsin so enzyme will not be digested? Relisten
3. Zinc homeostasis
   * Therefore, pancreas has a comparatively high vulnerability to toxicity.

Loss or decrease cobalamin –> gut issues = IBD, etc.

Question 14

• Enzyme secretion is ___________ of the diet (e.g. ______, __________ etc.)
• High protein diet → acinar cell ___________ or ____________
• Low protein diet → acinar cell _______

Answer 14

• Enzyme secretion is dependent of the diet (e.g. protein, carbohydrate etc.)
• High protein diet → acinar cell hypertrophy or hyperplasia
• Low protein diet → acinar cell atrophy

Question 15

Answer 15

Exocrine pancreatic atrophy in a pig.

Depletion of zymogen granule, atrophy of acini
Example of starvation in a pig

Question 16

What is the pathogenesis of pancreatitis?

Answer 16

• Pathogenesis:
• Pancreatic injury → release of pancreatic enzymes (esp.
  trypsin) into the surrounding parenchyma → further enzyme
  activation & autodigestion of the pancreatic tissue →
  necrosis & pancreatitis → inflammation

does not necessarily have to be inflammation of the pancreas, can also be necrosis of pancreas

Question 17

What are the causes of pancreatitis?

Answer 17

• Obstruction of the duct (s)
• Direct injury to acinar cells
• Disturbances of enzyme trafficking within the cytoplasm of
  acinar cells

Question 18

If you eat a high fat diet, pancreas is working hard to digest those ______.

Answer 18

if you eat a high fat diet, pancreas is working hard to digest those lipids.

Question 19

List the risk factors of pancreatitis in dogs?

Answer 19

• Middle-aged to older dogs
• Obesity
• Miniature Schnauzers, Miniature Poodles, Yorkshire Terriers
• High-fat diet
• Drugs
• Underlying diseases: Hyperadrenocorticism, hypothyroidism,
  hypertriglyceridemia

Question 20

What lesions will you typically see in a case of pancreatitis?

Answer 20

Lesions:
* Fat necrosis → saponification of fat
* Necrosis of blood vessels → thrombosis and hemorrhage
* Inflammation
* Fibrosis
* If ~90% of pancreatic tissue is loss, dogs may develop signs of
exocrine pancreatic insufficiency +/- endocrine pancreatic
insufficiency (diabetes mellitus)

• loss of pancreatic tissue –> langerhaan cells –> insulin resistance –> exocrine pancreatic insufficiency and diabetes mellitus

Question 21

What are the systemic effects of acute pancreatitis?

Answer 21

Systemic Effects of Acute Pancreatitis
Secondary to the release of inflammatory mediators and
activated enzymes from the damaged pancreas
* Gastrointestinal signs (vomiting, diarrhea, anorexia)
* Hemorrhage
* Shock
* Disseminated intravascular coagulation
* Systematic inflammation
* Organ failure

Question 22

Question 23

Answer 23

Acute Pancreatic Necrosis, Acute Pancreatitis, Pancreas, Dog.

Question 24

Answer 24

Chronic Pancreatitis, Pancreas, Dog

Question 25

Describe the role of Inflammation in Acute Pancreatitis * _________ and __________ also play a key role in inflammatory response in acute pancreatitis. * FDA conditionally approves first drug to manage ______ onset of pancreatitis in _____ in Nov 2022: * Fuzapladib sodium monohydrate (fuzapladib): a ________ function-associated activation (LFA-1) _________ that blocks ________ extravasation.

Answer 25

* Neutrophils and macrophages also play a key role in inflammatory response in acute pancreatitis. * FDA conditionally approves first drug to manage acute onset of pancreatitis in dogs in Nov 2022: * Fuzapladib sodium monohydrate (fuzapladib): a leucocyte function-associated activation (LFA-1) inhibitor that blocks neutrophil extravasation.

Question 26

Neutrophils are recruited to site of inflammation. Role in vessel via molecules expressed by endothelium. Neutrophil activated --> migrate through gap in endothelium --> enters pancreatic tissue. This drug helps neutrophil go out to tissue by limiting excess ____________.

Answer 26

Neutrophils are recruited to site of inflammation. Role in vessel via molecules expressed by endothelium. Neutrophil activated --> migrate through gap in endothelium --> enters pancreatic tissue. This drug helps neutrophil go out to tissue by limiting excess inflammation.

Question 27

Zinc Toxicosis * Source: _____ and ________ products (e.g. US _______), _______, _________ * Clinical signs: ? * Histopathology: Acute _____ cell ______

Answer 27

* Source: Alloys and galvanized products (e.g. US penny), pesticides, herbicides * Clinical signs: Vomiting, diarrhea, icterus, anemia, tachycardia, icterus, hemoglobinuria, hemoglobinemia, acute kidney and/or liver failure, pancreatitis, and DIC * Histopathology: Acute acinar cell necrosis

Question 28

What is pictured below?

Answer 28

Radiograph of a gastric foreign body (US penny) in a dog. The penny will eventually be digested in the stomach so even though it is coated by copper on the surface, inside is Zinc.

Question 29

What can be seen in the image below?

Answer 29

Radiograph of a fowl bird with metal in the gastrointestinal tract

Question 30

Question 31

Answer 31

Zinc toxicity in a dog. In the acute phase, there is basilar vacuolar degeneration within the acinar cells

Question 32

Exocrine Pancreatic Atrophy in Dogs * Predisposed breeds: German shepherd dog and rough-coated collies * Cause: unknown; maybe autosomal recessive * Clinical signs: maldigestion, diarrhea, malodorous feces, weight loss, polyphagia, poor coat * Gross: atrophied pancreas

Question 33

Answer 33

Juvenile pancreatic atrophy in a dog. can not produce enzyme for animals to digest

Question 34

Hyperplasia * Nodular hyperplasia of the pancreas: dogs, cats, cattle – no clinical significance

Question 35

What condition is pictured below?

Answer 35

Pancreatic Nodular Hyperplasia, Exocrine Pancreas, Dog. especially on older dogs --> it is this. no clinical significance do histopath to confirm it is not neoplastic

Question 36

Neoplasia 1. Adenomas - depends on size. hard to tell what clinical significance may be 2. Adenocarcinomas - May extend to peritoneum, duodenum (called carcinomatosis; different from metstastis --> tumors travel through vessels or lymphatics; this term means when tumor is seeded through peritoneal cavity). Can do both! - Metastasize to lymph node, liver, lungs - poor prognosis

Answer 36

Neoplasia * Adenomas * Adenocarcinomas * May extend to peritoneum, duodenum (carcinomatosis) * Metastasize to lymph node, liver, lungs

Question 37

Answer 37

Pancreatic Carcinoma, Dog.

Question 38

What is pictured below?

Answer 38

Pancreatic adenocarcinoma with peritoneal carcinomatosis, unknown species Seeding of neoplasia on omentum, throughout surface of organs in intestine. This is what you see in pancreatic carcinoma

Question 39

Answer 39

Peritoneal carcinomatosis due to hepatic carcinoma, Cat.

Question 40

Answer 40

Feline Paraneoplastic Alopecia * Ventral truncal alopecia with a shiny appearance to the skin. - reason why it is shiny is b/c there is follicular atrophy - do US to see if they have pancreatic or cholingier carcinoma * Usually associated with pancreatic carcinoma or cholangiocarcinoma.

Question 41

Answer 41

Question 42

gross images, patterns for hepatitis, accumulation of stuff in cells, etc. focus on that know function of cells we spoke abot i liver lecture may give some clincl scenarios and ask what the Dx mght be ?