Your source for clinical lab test information.

Sample

  1. This test is done in the serum of the patient.
  2. The random sample can be taken.
  3. Sample stable at 4 °C for 3 days
  4. Protect from the light because bilirubin is photo-oxidized (photosensitive).

Precautions

  1. Avoid hemolysis and lipemic serum which will give a false result.
  2. Avoid drugs which will increase the total bilirubin level like:
    1. Anabolic steroids.
    2. Antibiotics.
    3. Antimalarial drugs.
    4. Chlorpropamide.
    5. Methotrexate.
    6. An antihypertensive drug like methyldopa.
    7. Oral contraceptives.
    8. Antituberculous drugs like rifampin.

Pathophysiology

  1. Bilirubin is yellow to the green pigment of bile derived from the porphyrin structure of hemoglobin.
    1. Excessive bilirubin within cells and the tissue causes jaundice (Icterus) or yellowness of the skin.
    2. hyperbilirubinemia is caused by:
      1. Destruction of the RBCs like hemolytic jaundice.
      2. Diseases affecting the metabolism and excretion of bilirubin in the liver.
      3. Obstruction like gall stones or pancreatic tumors and certain drugs like:
        1. Chlorpromazine and phenothiazine derivatives.
        2. Estrogen hormones.
        3. Halothane anesthetic drugs.
  2. Bilirubin estimation is one of the liver function tests.
  3. It is raised in the hepatic and post-hepatic type of jaundice.
  4. Clinically jaundice appears when the level of bilirubin is more than 2 mg/dl.
  5. Direct (or conjugated) bilirubin. The Direct bilirubin dissolves in water (water soluble) and is synthesized in the liver from indirect bilirubin.

 

 

Normal Values

  1. Total bilirubin  = 0.3 to1.0 mg/dL or 5.1 to 17.0 mmol/L
  2. Direct bilirubin   =  0.1 to 0.3 mg/dL or 1.0 to 5.1 mmol/L
  3. Indirect bilirubin (total bilirubin minus direct bilirubin level) = 0.2–0.7 mg/dL

Another source Total bilirubin level

Age Premature  mg/dL Full-term   mg/dL Adult   mg/dL
Cord blood <2 mg <2.0  
0 to 1 day <8.0 1.4 to 8.7  
1 to 2 days <12.0 3.4 to 11.5  
3 to 5 days <16.0 1.5 to 12.0  
5 days to 60 years     0.3 to 1.2
60 to 90 year     0.2 to 1.1
>90 year     0.2 to 0.9

                                                                            
Raised level of direct bilirubin is seen in:

  1. Gallstones.
  2. Gallbladder tumors.
  3. Inflammatory scarring or obstruction of extrahepatic ducts.
  4. Extensive liver metastasis.
  5. Dubin-Johnson syndrome.
  6. Rotor syndrome.
  7. Drugs may cause cholestasis.

Possible References Used

Back to tests