Liver Function Test Flashcards
1
Q
What are the classifications of liver disease
A
- Infection (Viral, bacterial, parasitic)
- Toxic/drug induced
- Autoimmune
- Biliary tract obstruction
- Vascular
- Metabolic
- Neoplastic
2
Q
Causes of acute hepatitis
A
- Poisoning (paracetamol)
- Infection (Hep A-C)
- Inadequate perfusion
3
Q
Outcome of acute hepatitis
A
- Resolution in majority of cases
- Progression to acute hepatic failure
- Progression to chronic hepatic damage
4
Q
Common causes of chronic liver disease
A
- Alcoholic fatty liver
- Chronic active hepatitis
- Primary biliary cirrhosis
5
Q
Unusual causes of chronic liver disease
A
- a-1 AT deficiency
- Haemochromatosis
- Wilson’s disease
6
Q
Define cholestasis
A
Failure to produce/excrete bile
7
Q
Result of cholestasis
A
Accumulation of conjugated bilirubin in the blood, leading to jaundice
8
Q
What does liver failure result in
A
- Inadequate synthesis of albumin, leading to oedema and ascites
- Inadequate synthesis of clotting factors, resulting in bruising
- Inability to eliminate bilirubin, causing jaundice
- Inability to eliminate nitrogenous waste (e.g. ammonia) giving rise to hepatic encephalopathy
9
Q
What do current liver function tests cover
A
- Albumin
- ALT (+ AST)
- ALP (+ gamma-GT)
- Bilirubin
10
Q
Why measure albumin
A
Synthetic function
11
Q
Why measure ALT
A
Aminotransferases for hepatocellular damage
12
Q
Why measure ALP
A
For biliary epithelial damage and obstruction
13
Q
Why measure bilirubin
A
For cholestasis
14
Q
Advantages of current liver function tests
A
- Cheap, widely available, interpretable
- Able to direct next subsequent investigation (e.g. imaging)
15
Q
Disadvantages of current liver function tests
A
- Does not assess liver function
- Lack of complete organ specificity
- Lack of disease specificity
- May be over-sensitive
