| A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # |
Bilirubin Direct
Test CodeBILID
Alias/See Also
Epic: LAB52
Preferred Specimen
Specimen Type: Serum
Collection Container: Serum gel
Specimen Volume: 3 mL
Minimum Volume
0.1 mL
Instructions
- Centrifuge and separate cells after clot formation and within 4 hours of collection.
- Protect specimen from bright light.
Transport Container
Plastic vial
Specimen Stability
Room temperature: 2 days
Refrigerated: 7 days
Frozen: 3 months
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Unlabeled, mislabeled, wrong tube type, QNS, hemolyzed, or lipemic.
Methodology
Diazo Reaction
Setup Schedule
Daily
Report Available
Same day
Reference Range
0.0 – 0.5mg/dL
Clinical Significance
RBC's at the end of their circulating life are broken down in the reticuloendothelial system, mainly the spleen. The resulting heme, once the iron is removed, is then converted to bilirubin, and accounts for about 80% of the 300 mg of bilirubin formed daily. Other sources of bilirubin include the breakdown of myoglobin & cytochromes and the catabolism of immature RBC's in the bone marrow.
Once formed, bilirubin is transported to the liver bound to albumin. This fraction of bilirubin is referred to as indirect or unconjugated bilirubin. In the liver, bilirubin is conjugated to glucuronic acid to form conjugated bilirubin. Conjugated (direct) bilirubin is excreted via the biliary system into the intestine. Serum levels of direct bilirubin are normally negligible.
Direct bilirubin is the sum of the conjugated fractions. Direct bilirubin is elevated in conditions causing hepatic obstruction, hepatitis, cirrhosis, several inherited enzyme deficiencies, and inherited defects in canalicular excretion.
Once formed, bilirubin is transported to the liver bound to albumin. This fraction of bilirubin is referred to as indirect or unconjugated bilirubin. In the liver, bilirubin is conjugated to glucuronic acid to form conjugated bilirubin. Conjugated (direct) bilirubin is excreted via the biliary system into the intestine. Serum levels of direct bilirubin are normally negligible.
Direct bilirubin is the sum of the conjugated fractions. Direct bilirubin is elevated in conditions causing hepatic obstruction, hepatitis, cirrhosis, several inherited enzyme deficiencies, and inherited defects in canalicular excretion.
Performing Laboratory
Inova Laboratories
2832 Juniper Street
Fairfax, VA 22031
Additional Information
ILS Direct Bilirubin Abbott Alinity Job Aid
Last Updated: April 11, 2023
Last Review: N. Wolford, March 6, 2023