Bilirubin, Direct, Serum
Use
The Bilirubin, Direct, Serum test is important for evaluating jaundice and liver function by measuring the level of conjugated bilirubin. This test helps in understanding various liver diseases and conditions characterized by abnormal bilirubin metabolism and excretion, such as Dubin-Johnson syndrome, Rotor syndrome, idiopathic neonatal hepatitis, and biliary atresia. It also assists in assessing liver damage and monitoring conditions that impede bilirubin uptake, storage, and excretion.
Special Instructions
Patient's age and sex are required for processing the test. It is important to protect specimens from light during collection, storage, and shipment to ensure accurate test results.
Limitations
The test may produce falsely low results if the specimen is grossly hemolyzed due to hemoglobin interference with the diazo reaction. Falsely elevated results may occur if samples contain photobilirubin created under intense blue light during phototherapy. The direct bilirubin assay measures not only mono- and diglucuronide conjugated bilirubin but also delta bilirubin that binds to albumin, thus requiring careful interpretation within clinical context.
New York Approved
Methodology
Automated Analyzer (Clinical Chemistry)
Biomarkers
LOINC Codes
- 1968-7
- 1968-7
Result Turnaround Time
1-2 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
0.5 mL
Minimum Volume
0.25 mL
Container
Amber vial
Collection Instructions
1. Within 2 hours of collection, centrifuge the specimen. 2. For serum gel tubes, aliquot serum into an amber vial within 6 hours; protect from light. 3. For red top tubes, aliquot serum into an amber vial immediately; protect from light. 4. Refrigerate or freeze serum.
Storage Instructions
Ship specimen in amber vial to protect from light.
Causes for Rejection
Gross hemolysis
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 6 hours |
| Refrigerated | 24 hours |
| Frozen | 30 days |