Pancreatitis

See also Pancreas pathology

Signalment

• Yorkshire terriers, Labradors, Miniature Schnauzers and Miniature Poodles are predisposed
• Middle-old aged dogs
• Increased risk with obesity, diabetes mellitus, hyperadrenocorticalism, prior GIT disease or epilepsy (?treatment associated).
• Male and speyed females > intact females.

Description

Is due to the activation of digestive enzymes within the pancreas leading to autodigestion of the gland. Can be referred to as Acute or chronic pancreatitis.

• Acute Pancreatitis is rapid onset inflammation of the pancreas with little or no pathological changes occuring post recovery. This may completely resolve or 'wax and wane' into the future.
• Chronic Pancreatitis is continued inflammation leading to irreversible pathological changes (fibrosis, atrophy) and possible decreases in function.

The specific cause is usually idiopathic but several risk factors exist:

1. Nutritional: including obesity, low protein and high fat diets, feeding of ethionine, hypertriglyceridaemia and fatty meals.
2. Drugs and toxins: including L-asparginase, oestrogen, azathioprine, potassium bromide, furosemide, thiazide diuretics, salicylates, tetracyclines, sulphonamides, vinca alkaloids, zinc toxicosis, cholinesterase inhibitor insecticides, cholinergic agonist and hypercalcaemia.
3. Pancreatic Duct obstruction: caused by biliary calculi, sphincter spasm, duct wall oedema, duodenal wall oedema, neoplasia, parasites, trauma and iatrogenic reasons.
4. Duodenal juice reflux, Pancreatic trauma, ischaemia and reperfusion: including duodenal juice reflux into the pancreatic duct, surgical intervention, shock, anaemia, venous occlusion and hypotension.
5. Other: including parasitic (babesiosis), viral, mycoplasmal, end stage renal disease, liver disease and auto-immune diseases.

Cats mainly suffer from mild chronic interstitial pancreatitis.

Diagnosis

History and Clinical Signs

• History of eating a fatty meal
• Anorexia
• Vomiting
• Abdominal pain
• Lethargy
• Depression
• Nausea
• Diarrhoea (sometimes with blood, fresh or melaena, due to the proximity of inflamed pancreas to the duodenum and colon)
• More severe cases may present in shock, acute renal failure, jaundiced (due to focal hepatic necrosis), or with cardiac arrhythmias or pulmonary oedema or pleural effusions, widespread haemorrhage or DIC
• Acute haemorrhagic pancreatitis may present as shock and collapse.
• Cranial abdominal mass
• Mild ascites
• Dehydration (Mild to moderate)
• Febrile
• A cats presentation is more variable. If severe, they present with lethargy and anorexia with vomiting (35%) and abdominal pain (25%) being reported less than in the dog. Mild chronic pancreatitis may show anorexia and weight loss.

Diagnostic Imaging

Survey Radiography: Rarely helpful but findings may include:

1. In the right cranial abdomen:
   1. Increased density
   2. Decreased contrast
   3. Decreased granularity
2. Stomach displaced to left
3. Angle widened between pyloric antrum and proximal duodenum
4. Involving the Descending duodenum:
   1. Displacement to the right
   2. Prescence of a medial mass
   3. Gas pattern
   4. Thickened walls
5. Gastric distension
6. Delayed barium passage indicating abnormal peristalsis

Exploratory Laparotomy/Necropsy Findings

• The pancreas will be oedematous, soft with fibrinous attachments to surrounding organs
• Free fluid within the peritoneal cavity
• Pancreas liquefaction if severe enough
• Formation of pseudocysts
• Omental and pancreatic haemorrhages
• Areas of fat necrosis

References

Hall, E.J, Simpson, J.W. and Williams, D.A. (2005) BSAVA Manual of Canine and Feline Gastroenterology (2nd Edition) BSAVA

Merck & Co (2008) The Merck Veterinary Manual