9.5.2: Pancreatic Disease Flashcards
Zymogens
The inactive form of digestive enzymes secreted by pancreatic acinar cells.
What mechanisms exist to prevent pancreatic enzymes digesting the pancreas?
Digestive enzymes are secreted as zygmogens which are cleaved by enterokinase to activate them.
Enzyme inhibitors prevent enzymes digesting pancreatic tissue.
Acute pancreatitis
Sudden onset inflammation of the pancreas.
Little to no permanent changes after recovery.
Chronic pancreatitis
Continuous inflammatory disease resulting in irreversible morphological changes e.g. fibrosis and atrophy
Can lead to permanent impairment of function e.g. EPI, Diabetes
Risk factors for pancreatitis
- Hereditary: certain breeds
- Hyperlipidaemia
- High fat meal (not in cats)
- Obesity (not in cats)
- In cats only: GI disease/ vomiting leading to bile reflex. Also triaditis (pancreatitis + IBD + cholangitis)
- Pancreatic ischaemia and hypoxia (e.g. shock, hypotension, occlusion of venous outflow during abdo surgery)
- Pancreatic trauma - RARE - surgical manipulation or biopsy
Which breeds are predisposed to pancreatitis?
Dogs:
- Miniature schnauzers - can also get idiopathic hypertriglyceridaemia which predisposes them to pancreatitis as well
- Yorkies
- Boxers
- Cocker Spaniels
- Poodles
- Dachshunds
Cats:
* Siamese
* Bengals
What common pathway occurs with pancreatitis, regardless of the cause?
Decreased secretion of pancreatic juices -> premature activation of digestive enzymes -> damages the exocrine pancreas so there is oedema, haemorrhage and necrosis of surrounding fat -> inflammation leads to recruitment of WBCs and cytokines
What complications can occur due to recruitment of WBCs and cytokines when pancreas becomes inflamed?
- Renal failure
- Multi-organ failure
Clinical signs of acute pancreatitis
- Lethargy / weakness
- Anorexia
- Vomiting
- Diarrhoea
- (if severe) shock and collapse
Clinical signs of pancreatitis are often non-specific and O may not realise subtle changes in behaviour are important.
Clinical exam findings with pancreatic disease
- Abdominal pain
- Cranial abdominal mass
- Mild ascites
- Dehydration
- Fever
- Jaundice - uncommon - occurs if there is obstruction of the bile duct due to inflammation or mass
Lab abnormalities with pancreatitis
1
Lab abnormalities with pancreatitis
2
Lab abnormalities with pancreatitis
3
Why might you (uncommonly) see jaundice in the patient with pancreatitis?
Jaundice occurs if there is obstruction of the bile duct due to inflammation or mass
Why would ALP be elevated in the patient with pancreatitis?
- Increased liver enzymes (e.g. ALP) are due hepatocellular injury from toxins draining from the pancreas
- Not much in cats - ALP has very short half life and may be gone by the time you test
Why is important to treat hypokalaemia in cats especially?
Hypokalaemia can cause anorexia and ileus in cats
Which is more sensitive vs more specific out of Spec PL and Snap PL?
- Snap PL is more sensitive; however, can give false positives
- Spec PL is more specific; however, can give false negatives
You have a dog with suspected pancreatitis. You run a Snap cPL. What will you do if the result is:
a) negative
b) positive
a) negative - you can be pretty confident the dog doesn’t have pancreatitis
b) positive - send the sample away for Spec cPL to confirm diagnosis
Wht is the difference between cPLI and fPLI?
c = canine
f= feline
True/false: you can test amylase and lipase to confirm a diagnosis of pancreatitis.
False - don’t do this.
* Amylase and lipase are non specific
* They are influenced by hepatic, renal, intestinal disease, and neoplasia
* Don’t use to confirm pancreatitis
How is testing TLI (cTLI or fTLI) useful in diagnosing pancreatitis?
TLI = trypsin-like immunoreactivity
* Less sensitive and specific compared to PLI
* Increase rapidly in early stages of pancreatitis but decline quickly
* Limited diagnostic utility
Which of the following imaging modalities would you use to confirm diagnosis of pancreatitis?
a) radiography
b) ultrasonography
b) ultrasonography
(But need an experienced vet!)
* In pancreatitis, see enlargemtn of the pancreas, localised peritoneal effusion
* May see decreased echogenicity indicating pancreatic necrosis
* Hyperechogenicity may indicate pancreatic fibrosis (see with chronic pancreatitis) but also seen in benign pancreatic hyperplasia
* Can also look for pancreatic duct dilation
What might you see on abdominal radiographs when a patient has pancreatitis?
- Evidence of pancreatitis rarely seen; may see decreased detail / ground glass appearance of cranial abdomen
- Useful in ruling out other differentials, assessing displacement of abdo organs etc.
Treatment plan for pancreatitis
- Correct underlying fluid and electrolyte abnormalities
- Treat underlying cause
- Analgesia: in cats buprenorphine often works, in dogs start with methadone. May be very painful
- Anti-emetics: maropitant, ondansetron, metoclopramide CRI. Most animals feel nauseous even if not vomiting.
- Antibiotics if infectious cause identified: TMPS, metronidazole, clindamycin, enrofloxacin
- Steroids are generally to be avoided except in cats with chronic pancreatitis
When should you feed the patient with pancreatitis and what should you feed them?
- Start feeding once vomiting has been controlled (old advice was to withhold food - not anymore)
- Feed high carb, low fat commercial diet: roce, potato, pasta
- Fat and protein stimulate pancreatic secretions so avoid these
- Consider enteral feeding for anorexic cats e.g. NO tube, O tube
Clinical signs and treatment of pancreatic pseudocyst
Clinical signs and treatment of a pancreatic abscess
Long term treatment and control of pancreatitis
- Avoid high fat meals
- Fat restricted diet if recurrent bouts of pancreatitis
- Oral pancreatic enzyme supplements
- In cats with recurrent episodes: trial prednisolone 1mg/kg q12-24hrs for 1 week, tapering to 0.5mg/kg EOD as needed
Prognostic factors for pancreatitis
- Unpredictable and varies in severity
- Difficult to give accurate prognosis
- Most cases given supportive care respond spontaneously and do well long-term
- Acute pancreatitis can be life threatening
- Poor prognosis if continues to refuse food / can’t tolerate food
- In cats: hypocalcaemia with acute necrotising pancreatitis has a poor prognosis
Characteristics of pancreatic adenomas
1
Characteristics of pancreatic adenocarcinomas
2
Clinical signs of pancreatic neoplasia
- Similar to chronic pancreatitis: vomiting, diarrhoea, weight loss
- May have signs associated with metastatic lesions e.g. lameness, dyspnoea, bone pain
- Cats: paraneoplastic alopecia (shiny skin disease; alopecia of the ventrum, limbs and face)
Lab abnormalities in pancreatic neoplasia
- Lab results may be unremarkable
- May have neutrophilia, anaemia, hypokalaemia, bilurubinaemia, azotaemia, hyperglycaemia, increased liver enzymes
- Some dogs have very high serum lipase
- Hypercalcaemia can occur
Radiographic findings in pancreatic neoplasia
- Decreased contrast in the cranial abdomen
- May see mass
- Spleen may be caudally displaced
Ultrasonographic findings in pancreatic neoplasia
- Soft tissue mass in region of the pancreas
- If peritoneal effusion present, can sample it for cytology
- FNA of mass can be attempted (only successful in 25% cases)
Diagnosis of pancreatic neoplasia
- Often made at ex-lap or at PM
- Biopsy and histology required to establish definitive diagnosis
Treatment of pancreatic adenomas
- These are benign and often only found if causing clinical signs
- Of you find mass during ex-lap -> can do a partial pancreatectomy to establish diagnosis (never remove the whole pancreas!!!)
Treatment of pancreatic adenocarcinomas
- Often metastatic disease present by time of diagnosis
- Sites of metastatic disease: liver, abdo, thoracic LNs, mesentery, intestines, lung
- If no gross metastatic lesions, surgical resection can be attempted, but clean surgical margins are rarely achieved
- Overall prognosis is grave
What is pancreatic nodular hyperplasia and when do you see it?
- Occurs frequently in older cats and dogs
- Small nodules are found throughout the exocrine pancreas; this does not lead to functional change or clinical signs
- Usually an incidental finding
What disease process is shown here and what gross findings are associated with it?
Pancreas from dog with pancreatitis
* Oedematous tissue
* Soft
* Swollen
* Fibrinous adhesions
* Serosanguinous free abdominal fluid
* Pseudocysts
* Haemorrhages (pancreas and omentum)
* Abdominal fat necrosis
* Histology: multifocal infiltration of neutrophils + haemorrhage, necrosis, oedema, and vessel thrombosis
Describe the gross appearance of pancreatic neoplasia
Adenomas
* Solitary and contained with capsule
Adenocarcinomas
* Similar to adenomas
* May see evidence of metastatic spread to other organs
