Bilirubin (Total, Direct and Indirect)
What is Bilirubin (Total, Direct and Indirect)?
This test measures the amount of direct, indirect and total bilirubin in a person’s blood. This helps to screen or monitor liver disorders or hemolytic anemia and to monitor neonatal jaundice.
Why is Bilirubin (Total, Direct and Indirect) done?
The Bilirubin (Total, Direct and Indirect) test is done in case of signs and symptoms of:
Bile duct blockage
Liver-related metabolic problems
Jaundice in newborns
What does Bilirubin (Total, Direct and Indirect) Measure?
The Bilirubin (Total, Direct and Indirect) measures the amount of bilirubin present in the blood of a person. Bilirubin is an orange-yellow waste pigment produced by the normal breakdown of heme. The heme is a component of hemoglobin and is found in red blood cells. The liver processes the bilirubin and eliminates it from the body.
The life span of red blood cells is about 120 days. The heme which is released from the hemoglobin is converted into bilirubin which is called unconjugated bilirubin. It is then carried to the liver by proteins, where it gets attached to sugars and becomes conjugated bilirubin. The conjugated bilirubin enters the bile from the liver and passes to the small intestine where it is broken down by the bacteria and further eliminated in the stool. These breakdown products of bilirubin are responsible for giving the characteristic brown color to the stool.
A healthy adult body produces approximately 250 - 350 mg of bilirubin daily. About 85% of bilirubin comes from damaged or degraded RBCs while the remaining amount comes from the bone marrow or liver. The small amount of unconjugated bilirubin is released in the blood normally, but conjugated bilirubin is not present in the blood.
Both these forms of bilirubin can be measured or estimated and total bilirubin (sum of direct and indirect bilirubin) may be reported. In case there is an increase in levels of bilirubin, there will be yellowing of the skin and white of the eyes, giving the appearance of jaundice.
Interpreting Bilirubin (Total, Direct and Indirect) results
The normal values of total bilirubin may range from 0.30 mg/dL to 1.20 mg.dL.
Reference range may vary from lab to lab*
- Increased total bilirubin which is mainly unconjugated may be due to hemolytic anemia, transfusion reactions
- Increased total bilirubin which is mainly conjugated may be due to viral hepatitis, drug reactions, alcoholic liver disease, gall stones or any obstruction in the bile ducts
- Low levels of bilirubin are usually not a cause for concern and therefore not monitored
Answers to Patient Concerns & Frequently Asked Questions (FAQs) about Bilirubin (Total, Direct and Indirect)
Frequently Asked Questions about Bilirubin (Total, Direct and Indirect)
Tests Included (3 tests)
- Bilirubin Total
- Bilirubin Direct