Pancreas Flashcards
Role of pancreas in digestion
- Produce digestive enzymes
- Produce bicarbonate
Pancreatitis
Inflammation of the pancreas
-develops when the digestive enzymes are activated in the pancreas causing autodigestion
Mechanisms to prevent autodigestion
- Enzymes synthesized, stored and secreted as inactive zymogens
-they are activated in intestines
-enteropeptidases cleave activation peptides from trypsinogen to trypsin
-trypsin cleaves activation peptide off other zymogens - Digestive enzymes are segregated in lumen of rER
- Acinar cells have trypsin inhibitor which is stored and secreted with digestive enzymes
Pathophysiology of pancreatitis
- autodigestion
- abnormal mixing of lysosomes and zymogen granules in abnormal intracellular proteases
- activation of trypsinogen by lysosomal proteases
- trypsin activates the other digestive enzymes
What results from activated digestive enzymes?
-increases capillary permeability, damaged pancreas, activated vasoactive amine cascade
-local inflammation
-vasoactive peptides in circulation
What do vasoactive peptides result in?
-ARDS
-DIC
-hypotension
-myocarditis
-hepatocellular necrosis
-renal tubular damage
What increases severity of pancreatitis?
-consumption of protease inhibitors (local and in circulation)
-hypoperfusion
Potential etiologies for pancreatitis
- nutrition (obesity, fat content)
- hyperlipoproteinemia
- Drugs (azathioprine, diuretics, antibiotics)
- Duodenal reflux with vomiting or trauma
- alcohol ingestion
- ishemia
- duct obstruction
- hypercalcemia
- infection (toxo, FIP)
- Cushings disease
- Zinc
Risk factors in acute pancreatitis
-Mean 8-11yrs
-Breed: schnauzers, yorkies, poodles, siamese cats
-Obesity
-Prior GI diseases, diabetes mellitus, Cushings
**No risk with oral GCs, anesthesia, trauma
Feline risk factors for pancreatitis
-triad disease: combo of pancreatitis, IBD, cholangiohepatitis
Complications of pancreatitis
-cardiac arrhythmias
-DIC
-dyspnea (ARDS, effusion, pulmonary edema, PTE)
-ARF
-Diabetes mellitus
-sepsis
-bile duct obstruction, abscess, pseudocysts
How do you diagnose pancreatitis in dogs?
-history, physical exam
-amylase and lipase
-ultrasound
-PLI, cPL, precision PSL
How do you diagnose pancreatitis in cats?
-History, physical exam
-sometimes have leukocytosis on CBC
-Sometimes: liver enzymes high, hyperglycemia, hypokalemia
-low calcium
-Check ultrasound
-Pancreatic specific lipases
Clinical signs of pancreatitis in cats
-lethargy
-anorexia
-vomiting (35-46%)
-abdominal pain (19-25%)
Treatment of pancreatitis
-aggressive fluid therapy
-antiemetics
-early feeding (enteral preferred)
-analgesia
Exocrine pancreatic insufficiency
Progressive loss of exocrine pancreatic acinar cells
-results in inadequate digestive enzyme production and failure to absorb nutrients properly
-large functional reserve
-see signs when 85-90% of pancreas lost
Clinical signs of exocrine pancreatic insufficiency
-weight loss
-PP
-coprophagia
-pica
-diarrhea, responds to fasting, steatorrhea
-borborygmus
-flatulence
Potential etiology of exocrine pancreatic insufficiency
-Pancreatic acinar atrophy
-chronic pancreatitis
-idiopathic
-neoplasia
-feline?
Pancreatic acinar atrophy
-Unknown cause; post natal atrophy
- high prevalence in german shepherds (and other large breed dogs) due to autosomal recessive gene
Chronic pancreatitis
-common in humans; uncommon in dogs and cats
-may result in exocrine pancreatic insufficiency and diabetes mellitus
-underlying cause in feline exocrine pancreatic insufficiency
Pathophysiology of exocrine pancreatic insufficiency
Nutrient malabsorption; failure of intraluminal digestion due to abnormalities in small intestinal mucosa function
What are the abnormalities of the small intestinal mucosa?
-absence of trophic influence (growth)
-Small intestinal bacterial overgrowth
What causes small intestinal bacterial overgrowth? what are the changes that are seen in the small intestinal mucosa?
May be caused by lack of antibacterial pancreatic secretions
-Depending on bacterial species, results in changes in brush border enzyme activity, villus atrophy, competition for ingested nutrients
Diarrhea with exocrine pancreatic insufficiency
- osmotic
- Secretory
Osmotic diarrhea
Volume of feces is increased in proportion to % oral intake escaping absorption
-carbohydrate osmotically active
Secretory diarrhea
Hydroxyfatty acid production by bacteria releases enterotoxins, deconjugate bile salts
Trypsin-like immunoreactivity
-Standard testing for exocrine pancreatic insufficiency
*dogs value under 2.5 ug/L and clinical signs= diagnostic
and if no clinical signs=subclinical EPI
*cats, value below 8ug/L= diagnostic for EPI
Treatments for clinical exocrine pancreatic insufficiency
- uncoated vs enteric coated enzymes
*no differences except weight gain greater with coated
