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Auburn ECC > Hepatobiliary > Flashcards

Flashcards in Hepatobiliary Deck (110):
1

Milk thistle MOA?

Silymarin is active extract
antioxidant, free radical scavenger, inhibits lipid peroxidation, retards hepatic collagen formation

2

What are branch chain AAs?

valine
leucine
isoleucine

3

SAMe MOA?

hepatoprotectice
antioxidant
antiinflammatory
precursor to glutathione

4

ALT half life in dogs vs cats?

dog: 17-60 h
cat: 3.5 h

5

Ursodeoxycholic acid MOA?

antiinflammatory
immunomodulation
antifibrotic
promotes choleresis
decreases toxic effects of bile acids

6

zinc MOA

-essential trace mineral
-enhances ureagenesis
-increased glutathione peroxidase activity
-antifibrotic

7

Histologic lesion most common for drug/toxin hepatopathy?

centrilobular necrosis

8

How is ammonia produced?

End product of AA, purine, and amine breakdown by bacteria, metabolism of glutamine by enterocytes, and breakdown of urea by bacterial ureases

9

Ammonia is rapidly converted to ____ in the liver.

urea or glutamine

10

What does alkalosis cause with HE?

Pushes NH4+ to NH3 which can diffuse into the CNS

11

T/F: dogs with chronic hepatitis or more likely to have fever and abdominal pain than dogs with active hepatitis

False- acute is painful with fever, chronic more likely to have ascites

12

T/F: hepatomegaly is more common in acute hepatitis

True

13

List some mechanisms (pathophys) of hepatocellular injury

tissue hypoxia, lipid peroxidation, intracellular cofactor depletion, intracellular toxin production, cholestatic injury, endotoxic insults, hepatocyte plasma membrane injury

14

Why are hepatocytes especially susceptible to anoxia?

liver receives a mixture of venous and arterial blood

15

what does hypoxic damage to the liver lead to?

plasma membrane and cytosolic organelle injury secondary to ATP depletion; free radicals may cause oxidative cellular injury

16

how does cholestasis injure the liver?

leads to retention of bile acids that directly damages cellular organelles

17

how do endotoxins damage the liver?

stimulation of inflammatory cells to produce inflammatory mediators (prostaglandins and leukotrienes) that perpetuate inflammation in the liver; TNFalpha plays an important role as well

18

how does TNFalpha perpetuate hepatitis?

stimulates hepatocyte apoptosis through the Fas-Fas ligand pathway

19

Name categories and specific diseases causing hepatitis and cholangiohepatitis in dogs and cats

Idiopathic=canine chronic hepatitis, feline cholangitis complex, nonspecific reactive hepatitis
Viral- adenovirus type I, acidophil cell hepatitis, herpesvirus (neonates), FIP
Bacterial- feline cholangitis complex, Lepto, Bartonellosis, Tyzzer's dz, Salmonellosis, Listeriosis, Tularemia, Brucellosis, Helicobacter, Septicemia, Mycobacteria
Rickettsial- Ehrlichiosis, RMSF
Protozoal- toxo, neospora, leishmania, cytauxzoonosis, hepatozoonosis, coccidiosis
Parasitic- visceral larval migrans, dirofilariasis, liver fluke migration, schistomiasis, echinoccocus cysts
Fungal- Histo, blasto, coccidioides, aspergillosis, phycomycosis
Algal- protothecosis
Hepatotoxins- acetaminophen, aflatoxin, amiodarone, aspirin, azathioprine, azoles, carprofen, diazepam, halothane, methimazole, lomustine, phenobarb, tetracyclines, TMS, xylitol,, zonisamide

20

What are the two categories of feline cholangitis complex

neutrophilic vs lymphocytic cholangitis

21

T/F: neutrophilic cholangitis typically appears histologically as neutrophilic infiltration within the wall or lumen of the intrahepatic bile ducts

True

22

T/F: lymphocytic cholangitis typically appears histologically as neutrophilic infiltration within the wall or lumen of the intrahepatic bile ducts

False- lymphocytic typically is mixed inflammatory infiltrate (lymphocytes +/- plasma cells) within portal areas, associated with varying degrees of fibrosis and bile duct hyperplasia

23

What can be seen on histopath with chronic neutrophilic hepatitis that is different from acute neutrophilic hepatitis?

varying degrees of fibrosis and bile duct hyperplasia

24

What underlying conditions can be associated with neutrophilic cholangitis in cats?

IBD, pancreatitis

25

T/F: liver sampling is preferred over gallbladder bile for C&S in cats with suspect cholangitis?

false- prefer bile

26

Prognosis for cats with neutrophilic cholangitis? Possible sequelae?

Good prognosis; bile duct obstruction, acute necrotizing pancreatitis, sepsis, MODS

27

What is the definitive diagnosis for cats with lymphocytic cholangitis? Treatment?

Diagnose using liver biopsy and immunohistochemical staining; tx involved immunosuppressive glucocorticoid therapy

28

Canine chronic hepatitis is more common in what breeds?

cocker spaniel, bedlington terrier, dalmation, doberman, labrador, standard poodle, westies

29

T/F: there is evidence that supports an immune mediated process as perpetuating factor for canine chronic hepatitis?

true

30

what is common on histopath for canine chronic hepatitis?

lymphocytic/plasmacytic inflammation, occasionally neutrophilic, necrosis/apoptosis, evidence of regeneration, fibrosis or hyperplasia of ductal structures

31

Mainstay of tx for canine chronic hepatitis?

steroids; also other immunomodulatory drugs (ursodeoxycholic acid, metronidazole, azathioprine, cyclosporine)

32

Prognosis for dogs with chronic hepatitis?

depends on severity- can be excellent with slow progression or poor once cirrhosis develops

33

What is the role of copper in canine chronic hepatitis?

Unclear; may have elevated copper levels from cholestasis or elevated copper levels may damage hepatocytes; copper chelation has been shown to improve hepatic pathologic findings

34

Tx for copper induced hepatitis?

D-penicillamine, trientine, reduced dietary copper

35

Common histopath findings in nonspecific reactive hepatitis?

widespread inflammatory infiltrates (usually lymphocytes/plasma cells) in portal areas and parenchyma in the absence of hepatocellular necrosis

36

T/F: viral causes of hepatitis carry a fair to good prognosis?

false- it is poor

37

Pathogen responsible for infectious canine hepatitis?

adenovirus type I- only seen in young, unvaccinated dogs

38

Histopath findings for canine adenovirus type I?

large3 basophilic to amphophilic intranuclear inclusion bodies within hepatocytes and Kupffer cells (during 1st week of infection)

39

T/F: when FIP involves the liver, the disease is uniformly fatal

True

40

Common serovars of Lepto?

icterohaemorrhagiae, canicola, pomona, hardjo, grippotyphosa, bratislava

41

Which lepto serovars are more likely to have hepatic involvement?

icterohaemorrhagiae and pomona

42

How often is the liver involved in Lepto infections?

20-35% of cases; most commonly results in acute renal failure

43

Other organ systems besides liver and kidney that can be affected by Lepto?

uveitis, acute fever, pulmonary hemorrhage

44

Which hepatic enzyme is affected most severely with Lepto infections?

ALP

45

Histopath findings in the liver assoc with lepto?

coagulative necrosis, infiltration of lymphocytes and plasma cells

46

Tx of lepto?

penicillin for leptospiremic stage, doxy for carrier stage (doxy also works for leptospiremic stage)

47

Peliosis hepatitis and granulomatous hepatitis occur with which type of infectious hepatitis?

Bartonellosis

48

Preferred method of diagnosis for bartonellosis?

PCR on hepatic biopsy specimens

49

Tx options for bartonella in dogs?

azithromycin, doxy, enrofloxacin, rifampin

50

Commonly isolated bacteria in septicemia causing hepatitis?

Staph, Strep, enteric gram - organisms, Clostridium, Fusobacterium, Bacteroides

51

Possible histopath changes in the liver associated with drugs and toxins?

no changes, cellular swelling, steatosis, necrosis, cholestasis, inflammation, fibrosis

52

What are the 2 histologic types of cholecystitis in dogs and cats and which is most common?

Neutrophilic cholecystitis (most common) and lymphoplasmacytic follicular cholecystitis

53

T/F there are no breed predispositions associated with gall bladder disease.

False - Shelties and Cocker Spaniels

54

What 4 bacterial species are more commonly isolated from dogs or cats with cholecystitis?

E. Coli
Enterococcus sp
Bacteroides sp
Clostridium spp

55

Bacterial colonization of the bile duct may occur via what 2 mechanisms?

Reflux of duodenal bacteria, or hematogenous spread via the portal vasculature

56

What are 3 ultrasonographic findings you might expect with cholecystitis in dogs?

Hyper or hypoechoic thickening of the gallbladder wall, distention of the gallbladder and/or cystic duct, echogenic bile

57

What are the 3 types of necrotizing cholecystitis?

Type 1- areas of necrosis without gallbladder rupture
Type II- acute inflammation with rupture
Type III- chronic inflammation with adhesions and/or fistulae to adjacent organs

58

T/F -The majority of dogs with necrotizing cholecystitis have had bacterial infection

TRUE

59

What 4 imaging findings are sensitive indicators of gallbladder rupture?

Presence of echogenic fluid in the gallbladder fossa
Echogenic fluid throughout the abdomen
Echogenic reaction in the pericholecystic region
Radiographic evidence of decreased peritoneal detail

60

Effusion bilirubin concentration of what compared to serum bilirubin confirms bile peritonitis?

Greater than twice

61

What is the prognosis for surgical intervention in cholecystitis?

Guarded - high peri operative mortality, long term survival ranged from 61-82%

62

What are the 2 most common parasites associated with cholecystitis or cholangitis?

Platynosomum concinnum
Ampherimus pseudofelineus

63

With EHBDO, you would expect the gallbladder and cystic duct to dilate within what time frame and the intrahepatic bile duct to dilate within what time frame?

GB and cystic duct - 24 hours
Intrahepatic duct - 5-7 days

64

What is the proposed mechanism for development of choleliths in cholecystitis?

Increased gallbladder mucin production and decreased gallbladder motility associated with inflammation

65

What is the most common composition of choleliths in dogs and cats?

Calcium carbonate and bilirubin pigments

66

T/F - abdominal ultrasound is the imaging modality of choice to ID choleliths bc radioopaque choleliths are only reported in 24% of dogs and 48% of cats with symptomatic cholelithiasis

False- 48% dogs and 83% cats

67

List 5 Hepatobiliary disorders associated with EHBDO in dogs and cats

Cholangitis/cholecysitis/choledochitis
Gallbladder mucocele
Cholelithaisis
Neoplasia, cysts
Biliary trematode infestation
Inspissated bile

68

List 4 miscellaneous disorders (not pancreatic, duodenal, or hepatobiliary) associated with EHBDO

Regional mass or lymphadopathy
Local peritonitis
Iatrogenic (surgical ligation)
Trauma (stricture/fibrosis)

69

What has been proposed to be the genetic mechanism of gallbladder mucoceles in Shelties?

Insertion mutation of ABCB4 gene which encodes a protein that translocates phosphotidylcholine from the hepatocyte to the biliary canalicular lumen

70

What are the expected histopathological findings in a dog with hyperadrenocorticism and a gallbladder mucocele?

Cystic mucinous hyperplasia (in addition to secondary changes such as necrotizing cholecysititis)

71

What is the hallmark ultrasonographic appearance of a gallbladder mucocele?

Echogenic non-mobile material filling the gallbladder in a stellate or finely striated pattern, often with a hypoechoic rim along the wall

72

T/F - Bacterial infection of the gallbladder is uncommon in dogs with gallbladder mucocele

True -

73

T/F Biliary diversion techniques are associated with a worse prognosis and should be avoided

TRUE

74

What concurrent procedure should be performed at time of cholecystectomy?

Common bile duct must be catheterized and flushed thoroughly to ensure patency
Also submit gallbladder for histopath and aerobic/anaerobic culture and perform liver biopsy

75

What comprises medical management of a gallbladder mucocele? Is this recommended?

Ursodeoxycholic acid (UCDA) and levothyroxine (reported in 2 dogs, both of whom were hypothyroid), potentially also SAMe, amoxicillin, and omega fatty acids
Not recommended due to underlying necrosis of GB wall

76

List 4 potential benefits of UCDA

Causes choleresis
Immunomodulatory properties
May decrease mucin secretion
May improve gallbladder motility

77

What is the proposed mechanism regarding gallbladder infarction?

Infarction that may be part of a more generalized hypercoagulable state

78

T/F - Gallbladder infarction is frequently associated with gallbladder rupture

True - 50% of cases with gallbladder infarction were ruptured at surgery

79

What histologic findings were reported with gallbladder infarction?

Transmural coagulative necrosis with minimal to absent inflammation

80

T/F - Bacterial infection is more common in gallbladder infarction than gallbladder mucocele

True - 25% of gallbladder infarction dogs had infection (E.coli or clostridium) vs.

81

Why is there increased GI ulceration risk with liver failure?

because of decreased gastrin and histamine metabolism and compromised mucosal blood flow caused by potential portal hypertension

82

what type of PSS is the most commonly reported in dogs and cats?

single extrahepatic, congenital

83

what is a major contributing factor to worsening hepatic encephalopathy in dogs and cats with PSS and why?

hemorrhage into GI tract, because it acts as a large protein source for more ammonia production

84

t/f- pica is a common clinical sign reported in PSS patients?

true

85

what is the major goal of medical therapy for PSS prior to surgery?

decrease production and absorption of ammonia

86

what type of diet should be recommended for medical management in cases of PSS?

diet high in carbs and low in protein to decrease the building blocks for ammonia production; dairy and vegetable protein sources are less likely to cause worsening of HE compared to meat source proteins

87

how do abx help in the medical management of PSS?

reduce the number of bacteria available for producing ammonia

88

what 3 abx concentrate in the GI tract that are recommended for PSS medical management?

metronidazole, neomycin, amoxicillin

89

how are cathartics useful in PSS medical management?

they increase transit thru the GI tract and trap ammonium ions in the lumen, reducing ammonia absorption

90

what are the recommended options for fluid therapy since PSS patients often have hypoalbuminemia of chronic disease?

plasma or judicious synthetic colloids (ideally vetstarch >hetastarch)

91

what are 3 indications for using plasma transfusion for PSS dogs?

support intravascular volume, help maintain COP and provide coag factors

92

briefly summarize the 2 studies evaluating preoperative anticonvulsant therapy in dogs with PSS

One showed prophylactic anticonvulsants didn't reduce risk of postop neurologic signs but may have decreased their severity
The other showed using keppra was protective against the development of postop seizures (when starting >24 hrs prior to surgery)

93

Commonly used anticonvulsants and their doses for mgmt of PSS?

keppra 20 mg/kg PO q 8
phenobarbital 1-3 mg/kg PO q12 hrs
KBr loading dose 100 mg/kg POq6 x 4 doses, then 60-100 mg/kg SID

94

what is the criteria for determining a safe degree of PSS attenuation during surgery?

increase in portal pressure with temporary complete PSS attenuation of <10 cm H2O

95

what complication can occur if the portal pressure is >10 cm H2O with complete attenuation of the shunting vessel?

portal hypertension

96

what 2 devices can be used for gradual PSS occlusion?

ameroid ring constrictor and cellophane band

97

T/F- intrahepatic PSS are often large and patients may only tolerate partial PSS Ligation?

true; they are at higher risk for portal hypertension with excessive attenuation

98

what laboratory parameters are most impt to monitor in postop PSS patient?

PCV, TP, glucose, lactate, electrolytes, acid-base

99

what clinical parameters are recommended to monitor in the postop PSS patient?

HR, RR, temp, ABP, CVP, ECG, UOP, abdominal circumference, intraabdominal pressure, mentation/neuro status

100

what are the 3 major postop complications associated with PSS patients?

portal hypertension, coagulopathy, neurologic complications

101

what coagulation parameter has been shown to be increased in patients with PSS compared to healthy dogs?

aPTT

102

what is the range of reported incidence for dvlpmt of neuro complications in dogs with surgical PSS?

5-12%

103

reported incidence of cats with surgical PSS correction that develop neurologic signs?

37%, but 56% of them had resolution of neurologic signs

104

list some possible reasons/mechanisms that animals develop neurologic signs after attenuation of a PSS

-GI hemorrhage from portal hypertension
-abrupt decrease in GABA, aromatic amino acids and endogenous benzodiazepines once shunt has been attenuated
-systemic inflammation and oxidative stress, increased C reactive protein

105

T/F- there is no scientifically evaluated anticonvulsant therapy protocol for PSS patients and thus no proven benefit of one vs another

true

106

what is the perioperative mortality rate for extrahepatic PSS repaired using gradual attenuation?

5.5-7.1%

107

what is assoc with a worse prognosis in dogs with extrahepatic PSS?

lower WBC count and postop complications

108

mortality rate for dogs with intrahepatic PSS?

12.5%

109

predictors of short term outcome for dogs with intrahepatic PSS attenuation?

body weight, TP, albumin, and BUN

110

4 sources of ammonia?

degradation of intestinal protein and urea and colon by urease-producing microorganisms
intrahepatic degradation of AA from diet
enterocyte metabolism of glutamine
muscle catabolism