Liver Function tests

Question 1

What are the 7 markers used to test liver function?

Answer 1

• alanine transaminase (ALT)
• aspartate aminotransferase (AST)
• alkaline phosphatase (ALP)
• Gamma-glutamyltransferase (GGT)
• Bilrubin
• Albumin
• Prothrombin time (PT)

Question 2

Which 4 markers are used to distinguish between hepatocellular damage and cholestasis?

Answer 2

• ALT, AST, ALP and GGT

Question 3

Which 3 markers are used to assess livers synthetic function?

Answer 3

• Bilirubin, albumin, Prothrombin time

Question 4

What is ALT a good marker of?

Answer 4

hepatocellular injury

Question 5

What is ALP a good marker of?

Answer 5

a good indirect marker of cholestasis

Question 6

How many times the normal value of ALT is pathological?

Answer 6

x10

Question 7

How many times the normal value of ALP is pathological?

Answer 7

x3

Question 8

What does a raised ALP and GGT suggest?

Answer 8

Cholestasis (reduction or stoppage of bile flow)
Biliary epithelial damage and bile flow obstruction
Could also be raised due to alcohol and drugs (phenytoin)

Question 9

What does a raised ALP and normal GGT suggest?

Answer 9

non-hepatobiliary pathology
- could be anything that leads to bone break down as bone contains ALP (bony metastases, Vit D deficiency, bone fracture)

Question 10

What does it suggest if ALT is raised much more than ALP and vice versa?

Answer 10

ALT > ALP - hepatocellular pattern

ALP > ALT - cholestatic pattern

Question 11

The common causes of isolated jaundice (LFT normal)?

Answer 11

• Gilberts syndrome

- Haemolysis

Question 12

Jaundice + normal urine + normal stools - where is the problem?

Answer 12

Pre-hepatic cause

Question 13

Jaundice + dark urine + normal stools - where is the problem?

Answer 13

Hepatic cause

Question 14

Jaundice + dark urine + pale stools - where is the problem?

Answer 14

Post-hepatic cause (obstructive)

Question 15

Name the 3 causes of unconjugated hyperbilirubinaemia?

Answer 15

Haemolysis (anaemia)
Impaired hepatic uptake (drugs, congestive HF)
Impaired conjugation (gilberts)

Question 16

Name the 2 causes of conjugated hyperbilirubinaemia?

Answer 16

Hepatocellular injury

Cholestasis

Question 17

What are the 3 main causes of a fall in albumin?

Answer 17

• liver disease resulting in a decreased production of albumin (cirrhosis)
• inflammation triggers an acute phase response, which temporarily decreases the production of albumin
• Excessive loss of albumin due to protein-losing enteropathies or nephrotic syndrome

Question 18

what does the ratio between ALT/AST show?

Answer 18

ALT > AST chronic liver disease

AST> ALT liver cirrhosis and acute alcoholic hepatitis

Question 19

Look at the following presentation and choose between acute hepatocellular damage, chronic hepatocellular damage and cholestasis

ALT - Very raised
ALP - Normal or S.raised
GGT - Normal or S. raised
Bilirubin - Very raised

Answer 19

Actute hepatocellualr damage

Question 20

Look at the following presentation and choose between acute hepatocellular damage, chronic hepatocellular damage and cholestasis

ALT - Normal or S.raised
ALP - Normal or S.raised
GGT - Normal or S. raised
Bilirubin - Normal or S.raised

Answer 20

Chronic hepatocellular damage

Question 21

Look at the following presentation and choose between acute hepatocellular damage, chronic hepatocellular damage and cholestasis

ALT - Normal or S.raised
ALP - V.raised
GGT - V. raised
Bilirubin - V.raised

Answer 21

Cholestatsis

Question 22

What are the 3 causes of acute hepatocellular injury?

Answer 22

Poisoning
Infection (hep A or B)
Liver ischaemia

Question 23

What are the 4 causes of chronic hepatocellular injury?

Answer 23

Alcoholic fatty liver disease
Non-alcoholic fatty liver disease
Chronic infection (Hep B or C)
Primary biliary cirrhosis

Less common:

• Alpha 1 antitrypsin deficiency
• Wilsons disease
• Haemochromatosis