Study guide liver (Dark) Flashcards
1
Q
Normal liver morph and anatomy
A
- Sharp edges, dark mahogany color
- Acinus: bile secreting unit
- Lobule: blood filtering unit
2
Q
Liver blood flow
A
From portal vein => hepatic veins through the liver => central vein
3
Q
Bile flow
A
From bile canaliculi in central vein => bile duct in portal triad (periphery)
4
Q
Functions of liver
A
- secrete bile
- filter blood
- produce proteins, clotting factors
- metabolizes drugs and toxins
- gluconeogenesis
- breaks down ammonia
5
Q
CS liver dz
A
- Icterus (hyperbilirubinemia)
- Head pressing, neuro signs (ammonia build up)
- Bleeding, prolonged clotting times (liver synthesizes clotting factors)
- Edema (hypoproteinemia)
6
Q
Hyperbilirubinemia
Inc production
Dec excretion
A
- Inc production
- hemolysis
- congenital defect in bilirubin conjugation
- Dec excretion
- Hepatic dysfunction
- Cholestasis
7
Q
Hemolysis
Intravascular
Extravascular
A
- Intravascular
- RBC breakdown in blood vessels
- See hemoglobinemia
- Leptospira, babesia, acetaminophen, snake venoms, transfusion reaction, RBC fragmentation, hypoosmolarity, phosphofruktokinase deficiency
- Extravascular
- RBC breakdown outside vessels, in spleen
- see icteric serum
- cytauxzoon, Eperythrozoon, Mycoplasma hemofelis, IMHA, Neoplasia (hemangiosarcoma), RBC fragmentation
8
Q
Extrahepatic Cholestasis
Causes
A
- Choleliths
- Cholecystitis
- Biliary neoplasia
- Clonorchis sp
- Eurytrema sp
- Metorchis sp
- Platynosum sp
- Mucocele
- Pancreatic dz
- affects duodenal papilla, causes back up of bile => cholestasis
9
Q
Extrahepatic Cholestasis
CS
A
- Depression
- Dehydration
- Vomiting
- Diarrhea
- Anorexia
- Abdominal pain
- Icterus
10
Q
Bile duct obstruction
A
Often due to pancreatic disease, neoplasia
11
Q
Cystic mucosal hyperplasia
A
incidental finding
12
Q
Mucocele
A
- Entire lumen of gallbladder filled with mucus
- Animal is very sick
- will see biliary duct hyperplasia
13
Q
Biliary cyst
A
incidental finding
14
Q
Chronic Passive congestion
A
- Caused by resistance to outflow of blood in liver
- will see necrosis in centrilobular region, accentuated reticular pattern (nutmeg liver)
- often caused by obstruction in vena cava
- pheochromocytoma
- right sided heart failure
- thrombus
- heartworms
15
Q
Congenital PSS
Intrahepatic
A
- Usually found in large dogs
- macro or microvascular
- failure of ductus venosus to close
16
Q
Congenital PSS
Extrahepatic
A
- small breed dogs, not doing well
- portal vein to azygous
- portal vein to vena cava
- gastric vein to vena cava (common in cats)
- atresia of portal vein
17
Q
CS/TX PSS
A
- CS
- depression
- anorexia
- vomiting
- CNS
- Low BUN
- High ammonia
- TX
- med management
- sx
18
Q
Acquired PSS
A
- chronic hepatic injury with diffuse fibrosis
- results in portal hypertension
- shunt vessels form to allow blood in portal vein to bypass liver
- Ascites: increased hydrostatic pressure
19
Q
Steroid hepatopathy
A
- midzonal hepatocellular glycogen accumulation
- can be incidental if animal is on corticosteroids
- pathological if animal has cushings
20
Q
Lipidosis
A
- Physiologic: cattlein late pregnancy, lactation
- Pathologic: inc synthesis, inc lipolysis and uptake of FFA, decrease FA oxidation, decreased apoprotein synthesis and decreased lipoprotein excretion (cattle and cats)
21
Q
Feline fatty liver syndrome
A
- idiopathic hepatic lipidosis in cats
- typically obese, anorectic cats
- CS
- hepatic failure
- icterus
- hepatic encephalopathy
22
Q
Cirrhosis
A
- End stage liver dz
- cause:
- chronic inflammation
- bacterial/viral infection
- CCl4
- alkaloid plants in horses
23
Q
Causes of liver abscesses
A
- rumen acidosis
- ascending umbilical infection
- necrobacillus
- Tuberculosis
24
Q
Leptospirosis histo
A
small spirochetes in liver
25
Adenovirus
* CAV - 1 = infectious hepatitis
* CAV - 2= respiratory type that cross protects
* vax can cause corneal edema
26
Feline infectious peritonitis
* feline enteric Coronavirus
* perivascular pyogranulomatous inflammation of liver
* gold standard dz: liver biopsy with IHC
27
Toxins
* enter periportal, to liver, out central vein
* intrinsic
* produce consistenet hepatotoxicity
* causes
* pyrrolizidine alkaloids
* aflatoxins
* idiosyncratic
* produce sporadic hepatotoxicity
* Causes
* NSAIDS
* anesthetics
* anti-convulsants
28
Toxin processing in the liver
* biotransformation
* processing of toxins by liver
* bioactivation
* when biotransformation activates instead of deactivating toxins
* ex: sago palm, amanita toxins
29
Copper storage dz
* Bedlington terriers
* Gross: liver has nodules
* histo: will see copper on special stain
* will cause hemoglobinuria because sudden release of copper from hepatocytes causes lysis RBCs
30
Types of liver cancer
* Hepatoma (benign tumor hepatocyte origin)
* Biliary adenocarcinoma
* Hepatocellular carcinoma
* Metastasis of other tumor types
* Hemangiosarcoma
31
**Define lobular unit**
* Lobular unit: Portal triads form eges, centered around central vein
* Portal region: highest concentration of O2 rich blood and nutrients
* Midzonal region: intermediate O2 and nutrients
* Centrilobular/periacinar: lowest O2 conc
32
# define acinar unit
* Acinar unit: acinus + portal triads form edges
* zone 1 = portal region
* zone 2 = midzonal region
* zone 3 = centrilobular/periacinar region
33
**list possible clinical manifestations of liver failure w/ pathophysiolgy of CS**
* Jaundice: buildup of bilirubin
* Encephalopathy: elevated ammonia
* Edema/ascites: dec oncotic pressure from hypoalbuminemia
* Cutaneous lesions: photosensitization from failure to break down chlorophyll
* Clotting abnormalities: dec synthesis of clotting factors
* Abdominal pain
34
**Define Intrinsic toxin**
* consistently toxic
* can be experimentally reproduced
35
**define idiosyncratic toxins**
* toxicity is unpredictable
* cannot be reproduced experimentally
36
**pattern of damage**
**hematogenous spread of bacteria**
random, multifocal
37
**pattern of damage**
**Chloroform/CCl4**
* centrilobular: hypoxia
38
**pattern of damage**
**Alfatoxins, steroids**
* midzonal
39
**pattern of damage**
**toxins that don't need to be metabolized (pyrrolizidine, alkaloid in horses)**
* Periportal
40
**pattern of damage**
**Blue green algae, Theiler's dz, viruses**
* Massive
* necrosis of entire lobule/acinus
41
**possible causes for microhepatica**
* starvation
* portosystemic shunts
* hepatocellular necrosis
* chronic hepatocellular injury with secondary fibrosis
42
**possible causes of hepatomegaly**
* congestion
* amyloidosis
* lipidosis
* neoplasia
* acute diffuse hepatitis
43
**Common neoplasms of the liver**
* Hepatic nodular hyperplasia
* well organized
* common in older dogs
* Hepatomas
* benign neoplastic hepatocytes
* Hepatocellular carcinomas
* rare
* usually just 1 enlarged liver lobe
* Biliary carcinomas
* rare
* met to LN and lungs
* umbilicated (central necrosis)
* Metastatic
* hemangiosarcomas
* lymphosarcomas
