2. LFT’S
……..Group of biochemical tests used for diagnosis
and monitoring of liver disease
Hepatic Physiology:
Largest solid organ in the body
Performs over 500 chemical processes
Produces over 160 different proteins
3.
4.
5. BASIC PROCESSES IN LIVER DISEASES
• Acute &Chronic
Hepatitis
• Cirrhosis
Liver cell
damage
• Intra hepatic
cholestasis
• Extra hepatic
cholestasis
Biliary tract
involvement
6. CLASSIFICATION OF LFT’S
Group 1
• Tests based on Excretory Functions
Group 2
• Tests based on Synthetic Functions
Group 3 • Tests based on Serum Enzymes
Group 4
• Tests based on Metabolic Functions/ Special tests
Group 5
• Markers of Hepatic fibrosis
7. GROUP 1- TESTS BASED ON EXCRETORY
FUNCTIONS
SERUM- Total bilirubin, conjugated and un-
conjugated bilirubin
URINE – Bile pigments, bile salts and urobilinogen
10. GROUP 1- ESTIMATION OF BILIRUBIN
Serum Bilirubin:
Total bilirubin: 0.2–1.0 mg/dl
Conjugated bilirubin: 0-0.4 mg/dl
Un-conjugated bilirubin: 0.4-1.0mg/dl
Jaundice > 2mg/dl
(Serum bilirubin is elevated, when excretion
capacity of liver is decreased to 50%)
14. BROMOSULFTHALEIN (BSP)TEST
(EXCRETORY FUNCTION)
Very Sensitive Test
Single bolus dose of BSP – 5mg/kg bw
Serum concentration at 25 mtns and 45
mtns are measured
Normal cases – retention is <5% at 45 mtns
Increased retention - Useful to detect mild
impairment/ index of Liver damage
(Contraindication - Obstructive jaundice)
15. GROUP-2
TEST BASED ON SYNTHETIC FUNCTIONS
1. Serum Total proteins: 5.5 - 8.0 g/dl
2. Albumin: synthesized exclusively in liver
3.5 - 5.0 g/dL (Half-life:15-20 days)
Impaired synthesis in hepatic dysfunction, (cirrhosis-
<3.0g/dl)
severity of hypoalbuminemia α degree of damage
Low albumin after treatment is poor prognostic sign
16. GROUP-2
TEST BASED ON SYNTHETIC FUNCTIONS
3. Globulin: gamma globulin levels increased in
chronic conditions of liver
4. A:G Ratio : 1.5-2.5
reversed in cirrhosis
Severity of Hypoalbuminemia α Degree of damage
Low albumin after treatment is poor prognostic
sign
17. GROUP-2
TEST BASED ON SYNTHETIC FUNCTIONS
5. Prothrombin Time:
Except factor VIII, all Clotting factors are
synthesized by liver
PT collectively measure factor II, V, VII and X.
10-13 sec
Time increased in acute and chronic liver diseases
(Vit K should normal)
18. GROUP-3
TESTS BASED ON SERUM ENZYMES
1. Enzymes indicating Hepatocellular
damage (ALT, AST)
2. Enzymes indicating Cholestasis (ALP,
GGTP,5’NT)
19. GROUP-3 (ALT/SGPT)
More liver specific enzyme
Half-life 47hrs
Present in cytosol of hepatocytes and
released with mild cell damage (necrosis),
inflammation (hepatitis), drug toxicity.
Normal range: 5-40 U/L
Decrease levels indicates response to
treatment and good prognosis.
20. alanine -ketoglutarate pyruvate glutamate
Aminotransferase (Transaminase)
COO
CH2
CH2
C
COO
O
CH3
HC
COO
NH3
+
COO
CH2
CH2
HC
COO
NH3
+
CH3
C
COO
O
+ +
21. GROUP-3 (AST/ SGOT)
Found in heart, liver, muscle, intestine,
pancreas
Not very specific for liver disease
Normal range: 5- 30 U/L
In liver 20% activity is cytosolic and 80%
mitochondrial
Elevated 2 or 3:1 (vs. ALT) in alcoholics
22. (AST/ SGOT)
aspartate -ketoglutarate oxaloacetate glutamate
Aminotransferase (Transaminase)
COO
CH2
CH2
C
COO
O
COO
CH2
HC
COO
NH3
+
COO
CH2
CH2
HC
COO
NH3
+
COO
CH2
C
COO
O
+ +
24. GROUP- 3
(ALKALINE PHOSPHATASE)
Markers of Cholestasis
ALP – liver and bone (placenta, kidneys,
intestine, breast)
Normal Range: 3-13 KAU/dl, 40-125U/L
Moderate increase 2-3 times - hepatic
disease
High levels (10-12) - extra or intra hepatic
obstruction
V high levels (10-25) - bone disease
25. GROUP 3 (GGT)
catalyzed transfer of γ-glutamyl groups of
peptides to other amino acid
11 isoenzymes, abundant in liver, kidney,
pancreas, intestine, and prostate, spleen, heart,
brain but not in bone
Normal range: 10-30U/L
Along with ALP …good marker of cholestasis
26. GROUP 3 (GGT)
T1/2
7-10 days (28 days in alcohol-associated
liver injury)
Very sensitive to detect alcohol abuse
GGT levels in alcoholic liver disease parallels
alcohol intake
27. GROUP-4
TESTS BASED ON METABOLIC FUNCTIONS
Estimation of iron profile:
serum iron
serum ferritin
Galactose tolerance test
Fructose tolerance test
28. GROUP-4
TESTS BASED ON METABOLIC FUNCTIONS
Galactose tolerance test:
Basis: Normal Liver is able to convert Galactose
into glucose
Procedure: 40 gm orally or 0.5 gm/kgBW I/V is
given
Blood samples are collected at ½ hr intervals
Interpretation: 3gm or less Gal is excreted in urine
& normal gal in serum
Parenchymatous disease: Excretion is more
Can be done in Jaundice
29. GROUP- 4
TESTS BASED ON METABOLIC FUNCTIONS
Fructose tolerance test
Epinephrine tolerance test :
Principle: Response to epinephrine is evidenced
by elevation of Blood sugar and is directly
influenced by Glycogen stores of liver
Interpretation: Parenchymal and Glycogen storage
disease
32. Advantages
• sensitive, noninvasive
method of screening liver
dysfunction
• pattern of laboratory test
abnormalities to recognize
type of liver disorder
• assess severity of liver
dysfunction
• follow cause of liver
disease
Disadvantages
• lack sensitivity
– normal results in serious
liver disease
• not specific for liver
dysfunction
• seldom lead to specific
diagnosis
LIVER FUNCTION TEST
