What is Bilirubin?
When the liver works to reduce biliverdin and breakdown heme, bilirubin is produced. This orange pigment is excreted into the blood by liver cells. You find normal levels of bilirubin in the plasma of healthy patients. On a blood test, bilirubin levels are measured as an indication of liver health. High levels could mean liver cells are not releasing the bilirubin – eventually resulting in jaundice. The main symptom of jaundice is a yellowing of the skin. Liver disease and alcoholism are two causes of jaundice due to impaired liver function.
Normal Value Range
- Negative Pregnancy Adult: 0.3 to 1.3 mg/dL or 5.1 to 22.2µmol/L
- Pregnancy Trimester One: 0.1 to 0.4 mg/dL or 1.7 to 6.8 µmol/L
- Pregnancy Trimester Two: 0.1 to 0.8 mg/dL or 1.7 to 13.7 µmol/L
- Pregnancy Trimester Three: 0.1 to 1.1 mg/dL or 1.7 to 18.8 µmol/L
If increased total bilirubin is measured on lab tests, possible causes include cholangitis, hepatitis, biliary obstruction, Dubin-Johnson syndrome, mononucleosis, Gilbert disease, anemia (pernicious), fasting (prolonged), cirrhosis, alcoholism, neoplasia, hematoma, anemia (hemolytic), some forms of blood transfusion, congestive heart failure or pulmonary embolism.
Drugs can also affect total bilirubin, including phenothiazines, phenytoin, erythromycin, sulfonamides, penicillin, halothane, oral contraceptives, aminosalicylic acid, methyldopa and isoniazid.