Liver Function Tests – Part 3 – Differential Diagnosis of Jaundice (LFT) Lab Tests in Jaundice
- The serum of the patient is needed.
- Don’t expose the sample to the light.
- The liver function tests can differentiate various types of jaundice due to liver diseases.
The following tables can help to differentiate jaundice due to different causes (Etiological causes of jaundice):
|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
Table showing diagnostic tests in various diseases of the liver:
|Acute Viral Hepatitis||Bilirubin||raised (variable level)|
|SGOT||raised 10 to 100 times of the normal value|
|SGPT||raised 10 to 100 times of the normal value|
|Gamma GT||raised 5 times of the normal value|
|Chronic hepatitis||SGPT||mildly raised|
|Alkaline phosphatase||mildly raised|
|Gamma GT||mildly raise|
|Alcoholic liver||SGPT / SGOT||mildly raised|
|Gamma GT||raised 2 to 3 times of the normal value|
|Primary biliary cirrhosis||Bilirubin||raised|
|Alkaline phosphatase||raised 2 to 10 times of the normal value|
|SGPT / SGOT||moderately raised|
|Liver malignant tumor||SGPT / SGOT||maybe raised|
|Gamma GT||raised up 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:
- Bilirubin direct and indirect:
- Direct bilirubin is increased in obstructive jaundice.
- Indirect bilirubin is increased in hemolytic jaundice and in infections and toxic hepatitis.
- Urobilinogen quantitative:
- Increased in urobilinogen is seen in an infection of the liver and toxic hepatitis is reabsorbed from the intestine.
- There is also an increase in the various types of hemolytic diseases.
- The absence of urobilinogen is strongly suggestive of posthepatic biliary obstruction.
- Urine bilirubin:
- 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.
- Fecal urobilin:
- 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.
- Alkaline phosphatase:
- It is increased in the post hepatic jaundice, in cholangitis, and in primary or metastatic cancer.
- There may be a mild increase in hepatic jaundice.
- Cholesterol esters:
- It is a decrease in liver disease.
- Response to vitamin K:
- A poor response to vitamin K is seen in liver disease.
- Flocculation test:
- Positive cephalin flocculation or thymol flocculation tests are indicative of liver diseases like infections or toxic hepatitis.
- Galactose tolerance test:
- There is decreased tolerance to galactose is found in the liver disease.
- Liver needle biopsy:
- This will diagnose liver disease.
Diagnosis of Various Type 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|
|Extrahepatic biliary obstruction||Positive||Decreased or absent||Increased||Increased||Normal||Not satisfactory||Negative|
Please see more details in LFT part