Diseases of the Gallbladder and Extrahepatic Biliary System Flashcards
What’s the major difference between dogs and cats regarding bile duct entrance into the duodenum?
In dogs: the common bile duct joins with the minor pancreatic duct but exits separately
In cats: the common bile duct fuses with the major pancreatic duct and enters the duodenum together
Which breeds are predisposed to gallbladder stone (cholelithiasis)?
mini Schnauzer and mini Poodle
What’s a difference in gallbladder stone composition between dogs and cats?
Calcium stone are rare in dogs as they can absorb free calcium in the bile.
Cats can have calcium based stones
What’s the cause of gallbladder stones?
May be due to increased viscosity of the bile
What’s the clinical signs of gallbladder stone?
most patients are asymptomatic; the stones can lead to rupture –> bile peritonitis
- vomiting
- anorexia
- icterus
- abdominal pain
What are some common bloodwork abnormalities for gallbladder stone?
CBC:
- anemia of chronic disease
- neutrophilia, left shift with rupture
Biochem
- mild to moderate elevation in ALP, GGT, bilirubin
- hyperbilirubinemia precedes jaundice
- any ALP elevation in the cat = significant
- hypercholesterolemia becomes significant with obstruction
- hypoalbuminemia and hypoglycemia may be noted with sepsis and endotoxemia
What’s the imaging modality of choice for diagnosing gallbladder stones?
ultrasound!
- can assess for wall thickening and fluids
- cats: common bile duct >5mm = extrahepatic biliary obstruction
What’s the treatment for gallbladder stone?
medical dissolution rarely work – supportive therapy until it passes or surgery for more severe cases
cholecystectomies and choledochotomies
Which type of biliary stenting is more permanent?
self-expanding metallic stents.
- plastic ones are only good for weeks to months
What’s the role of bacteria in feline cholecystitis?
often considered secondary to inflammation
What are some clinical signs associated with cholecystitis?
mild cases = asymptomatic
moderate-severe case = abdominal pain, anorexia, vomiting, pyrexia
-jaundice = variable
- chronic cases = more difficult to detect as c/s are intermittent
How is cholecystitis diagnosed?
Ultrasound = gold standard
- bloodwork would be consistent with cholestasis: elevation in ALP, ALT, total bilirubin (esp in cats)
What’s the characteristic of biliary effusion?
should be greenish fluid - bile
- if the bilirubin is >2x serum, then the GB has ruptured
- extra- and intra-cellular bacteria is common
How is cholecystitis treated?
Medical: analgesics, IV fluids, antibiotics
- E coli, enterococcus spp, bacteroides, streptococcus, clostridium, helicobacter = most common
- ciprofloxacin and aminoglycosides
- need to be on antibiotics min 1month
- Severe cases or with peritonitis - cholecystectomy is preferred
How is emphysematous cholecystitis treated?
Surgery! high risk of rupture
antibiotic choice: fluoroquinolone, metronidazole, or chloramphenicol
In which species (cats or dogs) is biliary cystadenoma more common? where?
cats! mostly intrahepatic. rare in the dog
malignant transformation possible.
How is biliary cystadenoma treated?
They are typically incidental findings in older male cats
- surgery can be done if causing spacy occupying issues
Which tumour is the most common hepatobiliary carcinoma in the cat?
biliary carcinoma! it’s the 2nd most common in the dog
What are the most common clinical signs associated with parasites of the biliary system?
weight loss, vomiting, anorexia
What’s the most reliable method of confirming parasitic infection in the biliary system?
fecal sedimentation
What’s the treatment for parasitic infection in the biliary system?
usually praziquantel
- should consider pretreatment with prednisone and anti-histamine in case of high parasitic load to minimize inflammatory response
- surgery may be indicated for obstructive cases
What’s the pathophysiology for gallbladder mucocele?
persistent bile-laden semisolid to immobile sediment in the gallbladder leading to stretching and pressure necrosis of the gallbladder wall
- shelties and mini Schnauzer
What endocrine diseases could lead to increased risk of gallbladder mucocele?
Hyperadrenocorticism
- increased steroids –> increases unconjugated bile acids –> hydrophobic –> injury of biliary epithelium
Hypothyroidism
- inability for the sphincter of Oddi to relax, altered hepatic cholesterol metabolism, diminished bile secretion –> mucin solidification
What’s the predominate cause of gallbladder mucocele in the cat?
biliary stasis
what are some clinical signs of gallbladder mucocele?
lethargy, anorexia, vomiting, abdominal pain
- fever if there is peritonitis or bacterial cholecystitis
- 40% = icterus
What’s the gold standard for diagnosing gallbladder mucocele?
ultrasound! mucin = hypoechoic
blood work changes would be of typical cholestasis –> ALP. Can also have increased in ALT, GGT, and bilirubin
- marked elevation in cholesterol = biliary obstruction
