Description
In this collection we will learn about the liver and its function test and Some examples of Liver dysfunction
This will be useful for all medical students
Study Set Content:
Liver Function Tests
Test that measure biosynthetic function of the
Liver
Coagulation factors:
Except for factor VIII, blood clotting factors are
exclusively synthesized in hepatocytes
T1/2 of factor VII- 6 hrs / Fibrinogen – 5days
(shorter than albumin)
Rapid turnover – thus
measurement of clotting
factors
is the single best acute measure of hapatic
synthetic function (in the
diagnosis and assessment
of liver function in acute parenchymal liver disease
)
Liver Function Tests
Test that measure biosynthetic function of the
Liver
Coagulation factors:
What
is
measured
Prothrombin
Time
(PT)
-
collectively measures II/V/VII/X
Biosynthesis of factors II/VII/IX/X depends on Vit. K
PT may be elevated in hepatitis, cirrhosis and disorders
that result in Vit. K deficiency (eg obstructive jaundice)
Markedly prolonged PT (>5 secs above control), not
corrected by Vit. K is a poor prognostic sign in acute
viral hepatitis and other acute and chronic liver diseases
Hemolytic or Pre Hepatic Jaundice
Isolated elevation
of Bilirubin
(B
– Normal to 5
mg/dl, no
bilirubinuria)
Fractionate
bilirubin
Direct Bilirubin
> 15%
Direct Bilirubin
< 15%
W/U Hemolysis
Yes
No
Hepatocellular or Hepatic Jaundice
•
Bilirubin increased (Both fractions)
•
Bilirubinuria
•
↑ ALT, AST
•
ALP
–Normal to 3 fold ↑
Albumin ↓
Albumin
Normal
PT: prolonged
with failure to
correct
PT :
Normal
Albumin ↓
Albumin
Normal
•
PT: prolonged
corrected by Vit. K
PT: Normal
Obstructive or Post Hepatic Jaundice
•
Bilirubin increased (Both fractions)
•
Bilirubinuria
•
↑ ALT, AST (<500 U/L)
•
ALP: ↑ > 4 fold
Chronic
Isolated increase in
ALP
Fractionate ALP/ 5
’NT
or GGT
Assess the origin of
ALP
Summary
Liver Function
test
Clinical implication of abnormality
ALT
Hepatocellular damage
AST
Hepatocellular damage
Bilirubin
Cholestasis, impair conjugation, or biliary
obstruction
ALP
Cholestasis, infiltrative disease, or biliary
obstruction
PT
Synthetic function
Albumin
Synthetic function
GGT
Cholestasis or biliary obstruction
5`-nucleotidase
Cholestasis or biliary obstruction
