Endocrine 3 – Pancreas

Question 1

Main pancreatic outputs

Answer 1

• Exocrine: >90%
• Endocrine islets: 10%
  o Beta-cells (60-70%): insulin
  o Alpha-cells (20%): glucagon
  o Delta-cells (5%): somatostatin
  o Pancreatic polypeptide cells (10%)

Question 2

Hypoglycemia

Answer 2

• *young animals=big issue
• Impair brain function: potentially causing seizures, coma and death

Question 3

Type I diabetes mellitus

Answer 3

• Insulin-dependent (“Juvenile”)
• Destruction of beta-cells with progressive loss of insulin secretion
  o Insulin required for life after diagnosis
• May present with KETOACIDOSIS

Question 4

Type II diabetes mellitus

Answer 4

• Develops due to insufficient insulin secretion relative to metabolic demand
• *most common form in humans and CATS
• Middle to older cats
• *usually a gradual presentation
  o Insulin resistance and/or dysfunction of beta cells
  o Resistance is often secondary to obesity
• Start with a little bit of insulin and then become dependent on it

Question 5

Islet amyloid polypeptide (IAPP): amyloidosis

Answer 5

• Produced by pancreatic beta-cells
• Co-processed with insulin in response to glycemia
• *Common in obese cats, but does NOT mean they have diabetes

Question 6

What are the top causes of secondary diabetes mellitus

Answer 6

• *1. Dogs and cats with chronic, relapsing pancreatitis (ex. get pancreatic atrophy)
  o Destruction=leads to Type 1 DM
• *2. HIGH CORTISOL
  o Dogs with Cushing’s
  o Chronic steroid therapy
• 3. Cats with GH excess (GH secreting pituitary tumor)
• 4. Glucagon (glucagonomas)

Question 7

What are the lesions with diabetes mellitus?

Answer 7

• PU/PD/PP
• Weight loss, weakness
• Hepatic lipidosis: cats need to be overweight and anorexic
• Increased omental fat and TG formation
• *cataract=dogs
• Blood vessels: glomeruli highly susceptible to damage
• Peripheral demyelinating neuropathies occasionally seen: toe amputation

Question 8

Cushing’s and DM

Answer 8

1. Cushing’s can induce secondary DM
2. Cushing’s can complicate treatment of primary DM

Question 9

Adrenal diabetes

Answer 9

• Increase gluconeogenesis and decrease glucose use LEADS TO secretion of insulin LEADS TO adrenal diabetes

Question 10

Steroid hepatopathy

Answer 10

• Increased cortisol: decrease glucose usage, increased glycogen storage
• Diffusely enlarged at least 50%
• Histo: light colour=glycogen accumulation

Question 11

Hepatic lipidosis

Answer 11

• Yellow
• Floats in formalin

Question 12

Beta cell neoplasms=insulinomas

Answer 12

• *mostly in adult dogs and ferrets
• Often functional: producing excess insulin
• Adenomas are encapsulated
• Carcinomas: larger with features of malignancy and may metastasize
• Clinical: high serum insulin, low blood glucose and one ore more nodules on pancreas (often present with seizures)
• *single discrete tumor

Question 13

Glucagonomas

Answer 13

• Rare (maybe dogs)
• Produce excess glucagon
  o Secondary DM

Question 14

Gastrinomas

Answer 14

• Rare (dogs and cats)
• APUD cells in pancreas
• Produce excess gastrin: gastric ulcers

Question 15

Pancreatic nodular hyperplasia

Answer 15

• EXOCRINE hyperplasia
• Multifocal and very common
  o Usually moderate (some are extreme)
• Variable fibrosis from damage
• *may develop DM due to destruction

Question 16

Aortic body carcinoma OR chemodectoma

Answer 16

diagnosis made via histo between these 2

Question 17

Ferrets: common PM findings, diseases

Answer 17

• Lymphosarcoma: spleen or lymph nodes
• Adrenal tumors: *excrete estrogen (ex. alopecia: hair loss) LEFT
• Insulinoma: drop in blood glucose, weak
• Gastric ulcers
• IBD
• Cyst: RIGHT (still get estrogen excretion)
• Choroma: tumor at end of tail