Liver Function Tests

1. Dr. Shameera Begum

2. FUNCTIONS OF THE LIVER
Excretory
Function
Synthetic
Function
Metabolic
Function
Detoxification
Function
Storage
Function

3. TESTS TO ASSESS
EXCRETORY FUNCTION
Serum bilirubin
Urine and fecal urobilinogen
Urine bile pigments
Urine bile salts

7. TOTAL SERUM BILIRUBIN
Conjugated bilirubin
(direct bilirubin)
Soluble in water
Excreted in kidney
Unconjugated bilirubin
(indirect bilirubin)
Insoluble in water
Bound to albumin in
blood
Cannot pass through
glomeruli

8. • Normal range: 0.3 to 1.0 mg/dl
Total serum bilirubin
• Normal range: 0 to 0.2 mg/dl
Direct (conjugated ) bilirubin
• Normal range : 0 to 0.8 mg/dl
Indirect (unconjugated) bilirubin

9. JAUNDICE – Serum bilirubin > 2
mg/dl

13. TESTS WHICH ASSESS
HEPATIC INJURY (LIVER
ENZYMES)
 Serum Transaminases
 Aspartate aminotransferase (AST)/
Serum glutamic - oxaloacetic transaminase (SGOT)
 Alanine aminotransferase (ALT) /
Serum glutamic-pyruvic aminotransferase(SGPT)
 Alkaline phosphatase (ALP)
 Gamma glutamyl transferase(GGT)
 5’nucleotidase (5’NT)

15. • Normal range: 5 - 40 U/L
AST
• Normal range: 5 - 42 U/L
ALT
• 0.7 – 1.4
• > 2.0 in alcoholic hepatitis
• < 1.0 in acute viral hepatitis
AST/ALT ratio

16. • Children : 25 – 350 U/L
• Males: 25 -120 U/L
• Females: 25 -90 U/L
Serum ALP
• Normal range: 2-17 IU/L
Serum 5’-Nucleotidase
• Normal range – males: Upto 40 U/L
• females : Upto 25 U/L
Serum GGT

17. Serum aminotransferases
 Marker of acute hepatocellular injury
 Necrosis or death of cells containing these enzymes leads to
their release into the circulation
 Level correlates with extent of tissue damage
 Marked elevation of AST and ALT (> 15 times normal)
 Acute Viral hepatitis
 toxin induced hepatocellular damage
 Moderate elevation (5-15 times)
 Chronic hepatitis
 alcoholic hepatitis
 Mild elevation (1-3 times)
 Cirrhosis
 Cholestasis

18. Serum alkaline phosphatase
 Distributed widely in various tissues – liver, bones, intestine,
kidney and placenta
 Causes of Increased ALP – hepatobiliary causes, diseases of
bone, pregnancy
 hepatobiliary – Bile duct obstruction,primary biliary
cirrhosis,infiltrative diseases of liver
SERUM GGT
 Alcoholism (markedly elevated in acute alcoholic hepatitis)
 Cholestasis

20. TESTS WHICH ASSESS
SYNTHETIC METABOLIC
FUNCTIONS OF LIVER
Total serum proteins
Normal - 5.5 to 8.0 gm/dl
Serum albumin
Normal - 3.5 to 5.0 gm/dl
Serum albumin / globulin ratio
Normal - > 1.5

21. PROTHROMBIN TIME
 Most coagulation proteins are synthesised in liver
 Vitamin K dependent factors – II, VII, IX and X
 PT measures three factors (II, VII and X)
 PT prolonged in hepatocellular and obstructive jaundice
 NORMAL VALUE: 11 -13 sec

23. PHYSIOLOGICAL JAUNDICE OF
NEWBORN
 Transient increase in unconjugated bilirubin observed in almost
all newborns
 First appears during 24 – 72 hours of life
 Disappears by 7th to 10th day
 Does not exceed 15mg/dl
 Deficiency of glucuronyl transferase
 Treatment: Phototherapy ( unconjugated bilirubin to lumirubin)