Liver function tests - Kumar

Question 1

What is serum albumin a marker of?

Answer 1

• Synthetic function
• Gauging severity of chronic liver disease
• Falling albumin is a poor prognostic sign

Question 2

Why is interpretation of low albumin difficult?

Answer 2

• Many other causes of hypoalbuminaemia

* Malnutrition / urinary protein loss / sepsis

Question 3

When is differentiation between conjugated or unconjugated bilirubin important?

Answer 3

• In congenital disorders of bilirubin metabolism

* Or to exclude haemolysis

Question 4

What is prothrombin time a marker of?

Answer 4

•Synthetic function

Question 5

Why is prothrombin time a sensitive marker of both acute and chronic liver disease?

Answer 5

• It has a short half-life

Question 6

How is vitamin K deficiency excluded as a cause of a prolonged prothrombin time?

Answer 6

•By giving an IV bolus (10mg) of vitamin K.

Question 7

When does vitamin K deficiency commonly occur?

Answer 7

• binary obstruction: low conc. of bile salts = poor absorption of vitamin K

Question 8

What two transaminases are contained hepatocytes and leak into the blood with liver cell damage?

Answer 8

• Aspartate aminotransferase

* Alanine aminotransferase

Question 9

What is more specific to the liver, AST or ALT?

Answer 9

• ALT is more specific

* (AST is also present in heart, muscle, kidney and brain)

Question 10

High levels of AST may indicate what conditions?

Answer 10

• Hepatic necrosis / myocardial infarction / muscle injury / congestive cardiac failure

Question 11

What does a rise in ALT indicate?

Answer 11

• ONLY liver disease

Question 12

In viral hepatitis what is the ALT: AST ratio?

Answer 12

• ALT > AST

* UNLESS cirrhosis is present, in which case AST > ALT

Question 13

In alcoholic liver disease what is the ALT: AST ratio?

Answer 13

•AST > ALT

Question 14

In patients with liver disease without cirrhosis and have AST > ALT what is likely astrological agent?

Answer 14

•Alcohol or obesity

Question 15

Where is alkaline phosphatase present?

Answer 15

• Hepatic canalicular and sinusoidal membranes

* Bone / intestine / placenta

Question 16

Abnormal ALP is presumed to be from the liver when what other abnormal finding is present?

Answer 16

• Abnormal gamma-GT

Question 17

What happens to serum ALP levels in both intrahepatic and extra hepatic cholestatic disease?

Answer 17

• It is raised due to increased synthesis

Question 18

What has happens to serum ALP levels as result of hepatic infiltrations and cirrhosis?

Answer 18

• Raised

* (frequently in absence of jaundice)

Question 19

What are the two likely causes for very high ALP serum levels (>1000IU/L)?

Answer 19

•Hepatic metastases and PBC

Question 20

What liver biochemistry marker can be a useful indicator of alcohol intake?

Answer 20

• gamma-GT

Question 21

Is a slightly raised gamma-GT in the absence of other abnormal liver function markers a cause for concern?

Answer 21

• No

* Mild elevations of gamma-GT are common. Can occur with minimal alcohol consumption.

Question 22

In cholestasis, why do gamma-GT and ALP levels rises in parallel?

Answer 22

•They have a similar pathway of excretion

Question 23

What occurs to the globulin fraction in autoimmune hepatitis?

Answer 23

• It is raised

* (if it falls it indicates successful therapy)

Question 24

What does thrombocytopenia suggest (<150 x10^9/L)?

Answer 24

• Indicative of cirrhosis, unless another cause can be found.

Question 25

In alcohol excess how do RBCs often present?

Answer 25

• Macrocytic

Question 26

What does high levels of alpha-fetoprotein in non-pregnant adults suggest?

Answer 26

• Hepatocellular carcinoma

* Slightly raised with regenerative liver tissue in patients with hepatitis, chronic liver disease and teratomas

Question 27

What does high levels of serum and amniotic alpha-fetoprotein in pregnancy suggest?

Answer 27

• Fetal neural tube defects

Question 28

Raised urinary copper, and low serum copper and caeruloplasmin indicate what disease?

Answer 28

•Wilson’s disease