Gallbladder disease

Question 1

What two liver lobes is the gallbladder located between?

Answer 1

The right medial and quadrate lobes

Question 2

What duct connects the intrahepatic bile ducts to the gallbladder?

Answer 2

The cystic duct

Question 3

Name 4 components of bile

Answer 3

Cholesterol, lecithin, phospholipids, and bile salts

Question 4

What dog breeds are predisposed to choleliths?

Answer 4

Miniature Schnauzer, Miniature Poodle

Question 5

What are most canine choleliths comprised of? Why are calcium based choleliths very rare in dogs?

Answer 5

• Bilirubin, cholesterol, or a mix of both
• The canine gallbladder can absorb free calcium in the bile

Question 6

What are choledocholiths? Where can they form?

Answer 6

• Stones in the common bile duct
• Primary stones develop in the common bile duct
• Secondary stones develop in the GB - more common

Question 7

After a complete obstruction, when does dilation of the extrahepatic bile ducts develop? The intrahepatic bile ducts?

Answer 7

• Extrahepatic: dilation evident within 24-48 hours
• Intrahepatic: dilation evidence within 5-7 days

Question 8

In a case of bile peritonitis, the bilirubin concentration in the peritoneal effusion will be how many times greater than the serum?

Answer 8

At least 2x higher

Question 9

In cats, a GB wall thickness greater than what accurately predicts GB disease?

Answer 9

> 1mm

Question 10

Bacterial cultures of the bile are positive in what percent of patients with cholecystitis?

Answer 10

62%

Question 11

What is emphysematous cholecystitis?

Answer 11

Acute cholecystitis with gas producing organisms. Gas may accumulate in the lumen, wall, or pericholecystic tissues

Question 12

Name 3 ultrasonographic findings with biliary rupture?

Answer 12

Pericholecystic fluid, general peritoneal effusion, omental adhesions to the GB

Question 13

How is emphysematous cholecystitis treated?

Answer 13

Cholecystectomy recommended due to high risk of GB rupture and septic peritonitis

Question 14

What bacteria are most commonly isolated in cases of emphysematous cholecystitis?

Answer 14

E coli and Clostridium perfringens

Question 15

What chronic infection may contribute to the development of cholangiocarcinomas in the cat?

Answer 15

Parasitic infections with liver flukes (Platynosomum)

Question 16

How does a mucocele lead to GB rupture and bile peritonitis?

Answer 16

Expansion of the semisolid to immobile mucocele stretches the GB wall and disrupts blood flow, leading to pressure necrosis of the wall and rupture

Question 17

What are predisposing factors that contribute to mucocele formation?

Answer 17

Dyslipidemia, dysmotility of the GB, endocrine disease, exogenous steroids

Question 18

What breeds are predisposed to mucocele formation?

Answer 18

Shetland Sheepdogs, Cocker Spaniels, Miniature Schnauzers

Question 19

How is hyperadrenocorticism or steroid administration thought to result in mucocele formation?

Answer 19

• Steroids lead to higher levels of unconjugated bile acids in the extrahepatic biliary tree.
• Unconjugated bile acids are hydrophobic and lead to injury to the biliary epithelium
• The injured epithelium secretes more mucin => mucinous hyperplasia => mucocele formation

Question 20

How is hypothyroidism thought to result in mucocele formation?

Answer 20

Hypothyroidism impairs relaxation of the sphincter of Oddi, leading to decreased bile excretion. Liver cholesterol metabolism is also altered. Mucin then solidified and organizes

Question 21

How do acute and chronic pancreatitis differ histhopathologically?

Answer 21

Acute: neutrophilic inflammation, interstitial edema, necrosis of mesenteric fat
Chronic: lymphocytic inflammation, fibrosis, acing atrophy

Question 22

What percent of feline cholangitis cases are associated with extrahepatic bile duct obstruction?

Answer 22

64% in one study
40% of acute cases and 76% of chronic cases in another study

Question 23

In cats with liver disease, how did the time to maximum serum concentration and the half life of mirtazepine differ from healthy cats?

Answer 23

• Time to maximum concentration was prolonged (4 vs 1 hour)
• Half life was prolonged (13.8 vs 7.4 hours)
• Consider reduced frequency of administration

Question 24

In cats with lymphocytic cholangitis treated with prednisone or ursodiol, which group had prolonged survival?

Answer 24

Prednisolone survived longer (1 or 2 mg/kg/day)

Question 25

Compared to cat with lymphocytic cholangitis, cats with neutrophilic cholangitis had what clinicopathologic abnormalities?

Answer 25

Higher segmental and band neutrophil counts, higher ALT and bilirubin

Question 26

A single bacterial species is cultured from what percent of neutrophilic cholangitis cases? What bacteria are the most common?

Answer 26

>80% of cases, E coli most common

Question 27

Gallbladder agenesis occurs most commonly in what breed?

Answer 27

Chihuahua

Question 28

What clinicopathologic abnormalities and histopathology abnormalities are found with gallbladder agenesis?

Answer 28

Elevated ALT most common, common bile duct dilation without evidence of obstruction is common, most dogs had ductal plate malformations on liver biopsy

Question 29

In a 2016 study of bacterial cholangitis in dogs, what bacterial were most commonly isolated?

Answer 29

- E. coli (17 cases), Enterococcus (8 cases), Clostridium (5 cases) - E coli isolates were resistant to >3 classes of antibiotics in 10/16 cases

Question 30

What is the agreement between cytology and bile culture in identifying bacterial cholangitis?

Answer 30

Agreement was 85% (kappa 0.62) for all dogs/cats, but improved to 94% (kappa 0.84) if only including animals that had not received antimicrobials

Question 31

According to a 2017 paper, what is the sensitivity, specificity, and NPV of abnormal gallbladder ultrasound for predicting positive bile culture results in CATS?

Answer 31

Sensitivity 96%, specificity 49% NPV 96% - so cats with a normal gallbladder US are unlikely to have positive bile culture results Most common abnormality was GB wall thickening

Question 32

According to a 2017 paper, what is the sensitivity, specificity, and NPV of abnormal gallbladder ultrasound for predicting positive bile culture results in DOGS?

Answer 32

Sensitivity 81%, specificity 31%, PPV 20%, NPV 88% Less predictive than in cats

Question 33

What is an alternative to a fecal floatation for the diagnosis of Platynosomum infection?

Answer 33

Egg counts on bile obtained by ultrasound guided cholecystocentesis

Question 34

In dogs with extrahepatic bile duct obstruction due to pancreatitis, what was the survival rate? What percent survived with medical management alone?

Answer 34

79% survived Of the survivors, 94% were treated with medical management alone

Question 35

In dogs with extrahepatic bile duct obstruction due to pancreatitis, what was the time from the onset of clinical signs to increase in bilirubin, the peak bilirubin elevation, and initial improvement in bilirubin?

Answer 35

7, 8, and 15 days respectively

Question 36

What is the difference in mortality rate between dogs that undergo elective and non-elective cholecystectomy?

Answer 36

2% mortality in the elective group vs 20% in the non-elective group

Question 37

In cats undergoing choledochal stenting for EHBO, what percent survived to discharge? What was the MST?

Answer 37

78%, MST 931 days

Question 38

In cats undergoing choledochal stenting for EHBO, what percent had a recurrence of EBHO in the future?

Answer 38

39% - due to cholelithiasis

Question 39

What hormone was higher in dogs with mucoceles vs healthy dogs?

Answer 39

Leptin

Question 40

The odds of identifying a mucocele in Border Terriers was how many times higher than all other breeds?

Answer 40

85x higher

Question 41

What is the sensitivity and specificity of ultrasound for identifying GB rupture?

Answer 41

Sensitivity 56%, specificity 91.7%

Question 42

Dogs with a mucocele and gallbladder rupture/bile peritonitis were how many more times likely to die post-operatively than dogs with a mucocele and no rupture?

Answer 42

2.7 times more likely to die

Question 43

What is the survival time for dogs with mucoceles that survived at least 14 days after diagnosis?

Answer 43

Surgically managed: 1802 days Medically managed: 1340 days Medically managed, then needed surgery: 203 days

Question 44

What percent of dogs with mucoceles are hyper coagulable on TEG?

Answer 44

83%