Liver Clinical signs and diagnosis (lec 1-2) Flashcards
(113 cards)
1
Q
List hepatic causes of abdominal transudate effusion - ascites
A
Portal venous hypertension
Cirrhosis, failure of albumin production
2
Q
List non-hepatic causes of ascites (Specific conditions)
A
Right CHF intestinal caval syndrome neoplasia albumin loss
3
Q
List 2 hepatic causes of icterus (jaundice)
A
Hepatocellular damage
biliary obstruction
4
Q
List 2 non-hepatic causes of icterus
A
Haemolysis
Severe inflammation
5
Q
List a hepatic cause of encephalopathy
A
Hepatic failure - build up of ammonia and other endogenous toxins
6
Q
List 3 non-hepatic causes of encephalopathy
A
Forebrain or brainstem disease
Metabolic or toxic disease
Hypoxia
7
Q
List a hepatic cause of coagulopathy
A
Clotting factors not being produced by liver
8
Q
List 4 non-hepatic causes of coagulopathies
A
Rodenticide
Haemophilia
Platelet disorder or deficiency
DIC
9
Q
What 3 organs are the most likely to cause abdominal enlargement by organomegaly?
A
Liver
Spleen
Kidneys
10
Q
What are the 5 causes of extra-hepatic hepatomegaly?
A
Passive congestion RCHF Caudal vena caval obstruction Metastatic neoplasia Extra-medullary haematopoiesis
11
Q
What 2 causes of extra-hepatic hepatomegaly do you also usually get splenomegaly?
A
Passive congestion
Extra-medullary haematopoiesis
12
Q
What are the 8 causes of hepatomegaly by hepatobiliary aetiology?
A
Hepatic lipidosis Steroid hepatopathy Acute hepatotoxicity Inflammation Neoplasia Nodular hyperplasia Biliary obstruction Amyloidosis
13
Q
In a normal dog and cat is the liver palpable?
A
Yes
Can just feel it caudal to the costal arch
14
Q
What 8 things can hepatomegaly be identified and investigated by?
A
Palpation Radiography Ultrasound CBC Biochemistry Urinalysis FNA and cytology Exploratory laparotomy and biopsy
15
Q
Is abdominal effusion more common with liver disease in dogs or cats?
A
Dogs
Except for FIP with liver involvement
16
Q
What is the mechanism of formation of a transudate effusion?
A
Pressure differential
Either low oncotic pressure or increased hydrostatic pressure
17
Q
What is the mechanism of formation of a non-septic exudate effusion?
A
Inflammation that is not due to pyogenic infection
Usually sterile or viral
18
Q
What is the mechanism of formation of a septic exudate effusion?
A
Inflammation due to pyogenic infection
Usually bacterial
19
Q
What is the mechanism of formation of a haemorrhagic effusion?
A
Bleeding from lesion or coagulopathy
20
Q
What effusion type has the lowest protein and NCC concentration?
A
Transudate
21
Q
What effusion type has predominantly non-degenerate neutrophils?
A
Non-septic exudate
22
Q
What effusion type has predominantly degenerative neutrophils?
A
Septic exudate
23
Q
What effusion type has a HCT which is high compared to vascular HCT?
A
Haemorrhagic
24
Q
What is the mechanism of formation of a chylous effusion?
A
Rupture of lymphatics from intestine to thoracic duct
Trauma
RCHC
Idiopathic
25
What is the mechanism of formation of a uroabdomen effusion?
Urinary tract rupture
26
What is the mechanism of formation of a neoplastic effusion?
A neoplasm... duh
27
What effusion is milky/creamy pink in colour, has high triglycerid content and lymphocytes predominate?
Chylous effusion
28
What effusion is a yellowish fluid which will become inflammed over time, has a high BUN and creatinine that is 3-5 times that of blood
Uroabdomen effusion
29
What type of effusion is a neoplasm most likely to produce?
Modified transudate, nonseptic exudate or haemorrhagic fluid which will also have some neoplastic cell exfoliation
30
Effusions caused by liver disease are most commonly formed by what 5 mechanisms?
Increased portal venous hydrostatic pressure
Decreased intravascular oncotic pressure
Altered vascular permeability
Insufficient resorption
RAAS activation
-note effusion can be caused by one or more mechanisms
31
What two mechanisms can cause increased portal venous hydrostatic pressure?
Increased resistance to portal flow at the portal triad
| Hepatic venous/post hepatic caval congestion
32
What mechanism most commonly is the cause of an effusion from liver disease?
Increased portal venous hydrostatic pressure
33
What is the normal serum concentration of bilirubin
Under 10 micromol/L
34
What is the concentration that serum becomes icteric?
25 micromol/L
35
What is the concentration of serum that tissues become jaundiced?
50 micromol/L
36
What are the 3 major mechanisms that hyperbilirubinaemia can occur?
Prehaptic
Hepatic
Post-hepatic
37
What causes hyperbilirubinaemia pre-hepatically?
Intravascular or extravascular haemolysis or haematoma
38
What causes hyperbilirubinaemia hepatically?
Hepatocellular inability to process and excrete bilirubin
39
What causes hyperbilirubinaemia post-hepatically?
Extra-hepatic biliary obstruction
40
What part of serum bilirubin can make its way into the renal tubules from blood?
Only the non-protein bound conjugated fraction
41
Why can bilirubinuria be a normal finding in dogs?
They have a low renal resorptive threshold and their renal tubules can somewhat process bilirubin
42
Is bilirubinuria in cats and dogs always pathological?
Always in cats
| Not always in dogs
43
What are 4 differential diagnosis for pre-hepatic hyperbilirubinaemia?
Haemolytic anaemia
Intravascular - free Hb in plasma
Extravascular - destruction by splenic macrophages
Massive haematoma resorption
44
What are 5 differential diagnosis for hepatic hyperbilirubinaemia?
```
Hepatic lipidosis - cats
FIP - cats
hepatic neoplasia
Hepatotoxicity
Hepatitis
```
45
What are 6 differential diagnoses for post-hepatic hyperbilirubinaemia?
```
Pancreatitis
Cholangitis
Mass obstructive lesion
Cholelithiasis
Biliary rupture
Sepsis
```
46
What can you identify with a PCV/TP and blood smear in an icteric animal?
If it is a regenerative anaemia - rule in/out prehepatic cause and assess hydration
47
What can you identify with CBC, serum biochemistry and urinalysis in an icteric animal?
```
Assess hepatocellular and cholestatic enzymes
Liver function
Inflammation
Abnormal circulating cells
Indirect indicators of liver function
Degree of bilirubinuria
Involvement of other organs
```
48
What do you use diagnostic imaging (ultrasound) for in an icteric animal?
Asess biliary tree
Pancreas
Other organs
Liver parenchyma
49
What is hepatic encephalopathy caused by?
Effects of endogenous toxins that have not been removed from the circulation by the liver - Most come from the intestines
50
What 2 main mechanisms causes hepatic encephalopathy to develop?
Significant reduction in liver functional mass
| Portal blood bypassing the liver
51
What 4 things contribute to the pathogenesis of hepatic encephalopathy?
Increased blood ammonia levels
Increased levels of aromatic amino acids
Increased short chain fatty acids, mercaptans, skatole and indoles
Altered CNS neurotransmitter activity
52
What 5 clinical signs may be seen with hepatic encephalopathy?
```
Motor dysfunction
Changed mentation/behaviour
Seizures
Cortical blindness
Hypersalivation - cats esp.
```
53
Failure of conversion of ammonia to urea and uric acid causes precipitation in what in urine?
Ammonium biruate crystals
54
Nausea, inappetance and vomiting from living disease is a result of a combination of what 5 mechanisms?
```
Disturbed metabolism
Increased endogenous toxins in circulation
Hyperbilirubinaemia
Liver distension and pain
GI bleeding
```
55
Why are coagulopathies common from liver disease?
Most coagulation proteins and inhibitors are synthesised in the liver
56
What clotting factors are vitamin K dependent?
2, 7, 9, 10
57
What does complete biliary obstruction or rupture prevent?
Prevents bile acid facilitation of fat absorption
58
By what 2 mechanisms can portal hypertension predispose to rupture?
Induce vascular congestion
| More fragile
59
By what 2 mechanisms can portal hypertension predispose to GI ulceration?
Poor GI mucosal perfusion from portal hypertension
| Splanchnic pooling of blood
60
What 5 mechanisms contribute to the cause of polyuria/polydipsia in liver disease?
Reduced hepatic metabolism of aldosterone and cortisol
Altered threshold for ADH release
Hypokalaemia -impairs ADH action at receptors
Low urea reduces medullary conc. gradient
Primary polydipsia - inc. thirst from hepatic encephalopathy
61
What breed is predisposed to copper storage disease?
Bedlington Terriers
62
What breeds are prone to copper accumulation?
WHWT
Skye terrier
Dalmation
Siamese cats
63
What breeds are prone to idiopathic chronic hepatitis?
Doberman
| Cocker spaniel
64
What breeds are prone to portosystemic vascular anomalies?
```
Yorkshire
Maltese
Pugs
Schnauzer
Cattle Dog
OESD
Wolfhound
Retrievers
DSH
Persians
Himalayan cats
```
65
What breeds are prone to amyloidosis?
Shar Pei
Abyssinian
Siamese
Oriental cat
66
What 3 liver disorders are more likely in young animals?
Toxic
Inflammatory
Congenital
67
What 2 liver disorders are more likely in older animals?
Chronic hepatopathies
| Neoplasia
68
What are 6 non-specific clinical signs/history that are associated with liver disease?
```
Anorexia
PU/PD
Vomiting
Diarrhoea
Weight loss
Lethargy
```
69
What are 5 specific clinical signs/history that are associated with liver disease?
```
Stunted growth
Hepatotoxic drug
Anaesthetic intolerance
Abdominal effusion
Icterus
```
70
When doing a clinical exam on an animal with suspected liver disease, what 6 things should you specifically look for?
```
Body condition score
Abdominal distension and pain
Mentation
Icterus and pallor
Liver palpation and splenomegaly present
Dermatological lesions
```
71
What is poikilocytosis?
The presence of abnormal RBC's
72
What are 4 potential red blood cell hematological abnormalities from liver disease?
Regenerative anaemia with spherocytes
Poikilocytosis
Microcytes in portosystemic shunt
Oxidative damage
73
White are 2 potential white blood cell haematological abnormalities from liver disease?
Evidence of inflammation
| Atypical cells
74
What do liver enzymes provide evidence for?
Hepatocellular and biliary damage.
| Do NOT provide any info on liver function
75
What does the magnitude of elevated ALT and AST reflect?
Extent of hepatocellular injury, but not the reversibility
76
Where does ALT come from?
Leaks from cytosol of hepatocytes when they are injured or necrosed
77
Other than hepatocellular damage what else can cause a rise in ALT?
Muscle injury
| Some drugs like corticosteroids and phenobarbitone
78
Where does AST come from?
Cytosol and mitochondria of hepatocytes
| However it is also found in most tissues
79
Where does ALP come from?
Membrane-bound enzyme that is released from cholestasis or enzyme induction
80
What 5 things can cause a rise of ALP?
```
Intra or extra-hepatic cholestasis
Bone lysis or remodelling
Endogenous and exogenous corticosteroids
Hepatic lipidosis - cats
Feline hyperthyroidism
```
81
Where is GGT from?
```
Hepatocyte microvilli
Biliary epithelium
Renal tubules
Mammary epithelium
Can also be induced in dogs by corticosteroids
```
82
In cats, what is the most sensitive enzyme test for cholestasis?
GGT
83
What 7 components are indicators of failure of hepatic synthesis and homeostasis?
```
Urea
Albumin and globulin
Glucose
Cholesterol
Coagulation factors
Ammonia
Potassium
```
84
What causes a low BUN concentration?
Failure of liver to convert ammonia to urea
85
What causes hypoalbuminaemia in liver disease?
Failure of albumin synthesis
86
What is the serum half life of albumin?
10 days
87
Chronic hepatopathies may have increased what 2 kinds of globulins?
Beta and gamma
88
When will glucose homeostasis suffer as a result of liver dysfunction?
When over 70% hepatic functional mass is loss
89
When may hypocholesterolaemia be seen as a result of liver disease?
Hepatopathies
| especially PSS and cirrhosis
90
When may hypercholesterolaemia be seen as a result of liver disease?
Severe cholestasis
91
What can be problematic about testing ammonia?
Needs to be immediately tested or need to separate and freeze serum
92
What is the most common electrolyte disorder with hepatopathy and may also worsen hepatic encephalopathy?
Hypokalaemia
93
How is bilirubin produced? And where is it conjugated?
Degradation of haem protein
| Conjugated in liver
94
Is measuring conjugated or unconjugated bilirubin the most direct reading?
Conjugated
95
Where is conjugated bilirubin produced/from?
Formed in hepatocyte, gets water soluble and excreted in bile
96
Where is unconjugated bilirubin produced/from?
Bilirubin is transported into the blood bound to albumin
97
What is bilirubinuria caused by?
Passage of conjugated bilirubin through glomerulus
98
What is the USG usually like in liver disease?
Hyposthenuric -inadequate concentration
99
What is testing for urobilinogen useful for?
Bugger all. It is rapidly oxidised so even normal animals can appear abnormal
100
What is serum bile acids a good test for?
Clinically significant hepatobiliary disease
| Congenital or acquired portosystemic shunting
101
Where are bile acids from?
Synthesised in the liver from cholesterol
| Then conjugated and secreted in bile -aids in lipid digestion
102
How are bile acids usually resorbed?
Resorbed from ileum
Undergo enterohepatic recirculation
Extracted from portal blood by hepatocytes
103
During cholestasis there is an increased level of bile acids, what else may this contribute to? (what does it damage)
Contribute to hepatocellular membrane damage by detergent action
104
Why isn't serum bile acids measurement a good test if cholestasis is present?
It increases the levels via reflux into blood stream - Artifically elevates
105
What 2 things is radiography unhelpful for?
No information on parenchymal change
| If lots of peritoneal effusion present
106
What may you see on a radiograph if there is necrotic liver disease present?
Hepatic gas
107
What 3 things is ultrasound particularly useful for?
Guidance of FNA or tru-cut biopsy
Assessment of parenchymal change
Assessment of portal and hepatic venous system
108
What must you do before conducting a FNA?
Rule out a coagulopathy
109
What 4 things may be identified from a FNA?
Hepatic lipidosis
Neutrophilic inflammation
Lymphoma
Non-specific hepatopathy
110
What is the only thing that you can do with an FNA of the liver?
Cytology
111
What should you also request when sending a liver biopsy away?
Copper staining
Immunohistochemistry
PCR
112
Why is an exploratory laparotomy preferred to a percutaneous biopsy in the cat?
High morbidity and mortality associated with biopsy
| Usually want to also assess pancreas and SI at the same time
113
Why can a liver biopsy be more informative compared to an FNA?
It is a histopathological sample and therefore hepatic architecture can also be assessed
