L12: Pancreatic Dz in the Dog and Cat Flashcards
secretory functions of the pancreas
exocrine: into duodenum
- acini release digestive enzymes and cofactors
- ducts release HCO3 buffer
endocrine: into portal blood
- islets release hormones
route of digestive enzymes from pancreas
- packaged in membranes and transported toward the lumen
- routed through pancreatic acinar cell
pancreatic enzymes
- amylase and lipase (active form)
- proteolytic enzymes (inactive zymogens; Ca needed to activate)
activation of ___ required for activation of all other pancreatic zymogens
trypsinogen
trypsinogen – ? –> trypsin + activation peptide
enteropeptidase (trypsin)
Pancreatic Secretory Trypsin Inhibitor (PSTI)
inhibits trypsin from binding
why doesn’t the pancreas digest itself?**
- intracellular compartmentalization
- proteases formed in inactive form
- PSTI secreted in parallel with trypsinogen
- enterokinase is extrapancreatic
- low intracellular calcium (needed to activate proteolytic enzymes)
Colocalization theory
potential pathogenesis for Pancreatitis in which zymogens and lysosomes mix –> activation of trypsinogen –> autodigestion –> inflamm, edema, hemorrhage, necrosis, peripancreatic fat necrosis
Risk factors for pancreatitis
- Dietary: fat, indiscretion
- Pancreatic ischemia
- Reflux of duodenal contents-bile
- drugs
- duct obstruction
- genetic factors
- idiopathic
chars. of pancreatitis
- common
- usually more severe in dogs
- middle-aged dogs, all age cats
CS of pancreatitis (most to least common): DOGS
- vomiting (90%)
- weakness (80%)
- abd pain (60%)
- dehydration
- diarrhea
- anorexia
- depression
- fever
- abd distention
- cranial abd mass
- shock
- cardiac arrhythmia
- resp. distress
CS of pancreatitis (most to least common): CATS
lethargy (100%) anorexia (97%) dehydration hypothermia abd pain palpable mass dyspnea ataxia diarrhea (15%)
triaditis includes:
IBD, pancreatitis, colitis
clin path of pancreatitis: DOG SPECIFIC
- neutrophilia and L shift (55%) (L shift due to inflamm, not infection)
- thrombocytopenia (60%)
- anemia (30%)
clin path of pancreatitis: CAT SPECIFIC
- anemia (26%)
- hemoconcentration (13%)
- leukocytosis (30%)
- leukopenia (15%)
- changes may be due to stress alone!)
clin path of pancreatitis in general
- azotemia
- hypoalbuminemia
- hyperglycemia
- hypocalcemia (Ca can get sucked into suponification of fat)
- hyperlipidemia (due to disturbed fat metabolism)
- hyperbilirubinemia
- inc. liver enzyme activity (as pancreas swells, bile duct obstructed and bile backs up –> secondary damage to liver, translocation of bacteria possible
Dx of pancreatitis
- cPLI and fPLI (however not 100% sensitive or specific; do not rely on for dx! Can also be FB, cushings, etc)
- amylase and lipase and TLI unreliable
- histology = gold standard
cats more likely to get chronic/acute pancreatitis?
chronic, making fPL test less useful than in dogs because they can have intermittent fPL increases
rad findings with pancreatitis
- loss of serosal detail R cranial abd
- duodenum displaced laterally
- duodenum and colon gas-filled (sentinel loop)
- corrugated duodenal wall and/or pancreatic mass
pancreatitis on abd U/S
- hypoechoic and enlarged pancreas
- peripancreatic fat hyperechoic
when is biopsy indicated with pancreatitis?
(usually not indicated; changes may not correlate clinically)
chronic cases
mass lesions
tx of pancreatitis
- supportive (fluids, pain meds, anti-emetics)
- GI rest? (cons: prolonged anorexia, GI mucosal barrier)
- blood, plasma, or plasma expander
- parenteral abx (usually not needed)
- gradually reintroduce low fat food with clinical improvement
- return to normal diet if isolated episode
- keep on low fat diet if recurrent
goals for fluid therapy in tx of pancreatitis
- replace deficit
- replace ongoing losses
- maintenance
- use balanced electrolyte solution (ie. LRS)
- give K supplementation
when is surgical exploration of pancreatitis indicated?
- pancreatic abscess or mass
- prolonged bile duct obstruction
