Liver Function Tests:- Part 3 – Differential Diagnosis of Jaundice

Liver function tests

Differential diagnosis of jaundice

Sample

1. The serum of the patient is needed.
2. Don’t expose the sample to light.

• The liver function tests can differentiate various types of jaundice due to liver diseases.

 Differential diagnosis of jaundice and LFT findings:

Disease	Urine		Stool	Serum  Bilirubin	Serum cholesterol
Tests	Bilirubin	Urobilinogen	Bilirubin          Urobilinogen	Direct                       Indirect	Cholesterol
Viral Hepatitis	Inc	N or Inc	Dec                              Dec	Inc                             Inc	N or dec
Hepatitis due to drugs	Inc	N or Inc	Dec                            Dec	Inc                             Inc	N
Cholestatic Hepatitis	Inc	N or Dec	Dec                            Dec	Inc                             Slight Inc	Inc
Jaundice due to Cirrhosis	Inc	N or Inc	<1 indirect              >1 direct	Inc                              Inc
Extrabiliary obstruction	Inc	Dec	Dec +++                   Dec +++	Inc                              N or Inc	Inc mild to moderate

Inc = increased     N = Normal     Dec = Decreased

 Diagnostic tests in various diseases of the liver:

Disease	Lab Tests	Interpretation
Acute Viral Hepatitis	Bilirubin	raised  (variable level)
	SGOT	raised 10 to 100 times the normal value
	SGPT	raised 10 to 100 times the normal value
	Gamma  GT	raised 5 times the normal value
	Viral markers	positive
Chronic hepatitis	SGPT	mildly raised
	SGOT	mildly raised
	Bilirubin	persistently raised
Cirrhosis	SGPT	slightly raised
	SGOT	Slightly raised
	Bilirubin	mildly raised
	Alkaline phosphatase	mildly raised
	Gamma GT	mildly raise
	Prothrombin time	prolonged
Alcoholic liver	SGPT / SGOT	mildly raised
	Gamma GT	raised 2 to 3 times the normal value
	Albumin	decreased
	Globulin	raised
Primary biliary cirrhosis	Bilirubin	raised
	Alkaline phosphatase	raised 2 to 10 times the normal value
	SGPT / SGOT	moderately raised
Liver malignant tumor	SGPT / SGOT	maybe raised
	Alkaline phosphatase	raised
	Gamma GT	raised to 20 times the normal value
Cholestatic jaundice	Bilirubin	raised mostly conjugated
	Alkaline phosphatase	markedly raised
	SGPT / SGOT	mildly raised
	Gamma GT	markedly raised

Lab tests in jaundice:

1. Bilirubin direct and indirect:
   1. Direct bilirubin is increased in obstructive jaundice.
   2. Indirect bilirubin is increased in hemolytic jaundice and infections, and toxic hepatitis.
2. Urobilinogen quantitative:
   1. Increased urobilinogen is seen in an infection of the liver, and toxic hepatitis is reabsorbed from the intestine.
   2. There is also an increase in the various types of hemolytic diseases.
   3. The absence of urobilinogen is strongly suggestive of posthepatic biliary obstruction.
3. Urine bilirubin:
   1. There is an increase in the urine bilirubin is due to the excessive production of bilirubin and is usually because of pf the posthepatic type.
4. Fecal urobilin: 
   1. The absence of urobilin (stercobilin) in the stool indicates that no bilirubin is not entering the duodenum. This will lead to a clay-colored stool.
5. Alkaline phosphatase:
   1. It is increased in post hepatic jaundice, cholangitis, and primary or metastatic cancer.
   2. There may be a mild increase in hepatic jaundice.
6. Cholesterol esters:
   1. It is a decrease in liver disease.
7. Response to vitamin K:
   1. A poor response to vitamin K is seen in liver disease.
8. Flocculation test:
   1. Positive cephalin flocculation or thymol flocculation tests indicate liver diseases like infections or toxic hepatitis.
9. Galactose tolerance test:
   1. There is decreased tolerance to galactose is found in liver disease.
10. Liver needle biopsy:
    1. This will diagnose liver disease.

Diagnosis of Various Types of Jaundice:

Clinical condition	Urine bilirubin	Urine urobilinogen	Alk. Phosphatase	Bilirubin direct	Bilirubin indirect	BSP test	Ceph. Flocculation
Hepatitis with jaundice	Positive	Increased	Normal or slightly Increased	Normal or slightly increased	Increased	Increased retention	Positive
Hepatitis without jaundice	±	Increased	Normal	Normal	Normal	Increased retention	Positive
Hemolytic jaundice	Negative	Increased	Normal	Normal	Increased	Normal	Negative
Extrahepatic biliary obstruction	Positive	Decreased or absent	Increased	Increased	Normal	Not satisfactory	Negative

Please see more details in the LFT.

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