Direct Bilirubin (DBI)

 CPT Code:  82340
 Specimen:  Serum (preferred) or plasma
 Volume:  1 mL
 Minimum Volume:  0.5 mL
Container: Red-top tube, gel-barrier tube, or green-top (lithium heparin) tube
Methodology: Colorimetric
Collection:

 Serum and plasma specimens should be separated from cells within 2 hours after venipuncture.

Specimens should be free of particulate matter.  To prevent the appearance of fibrin in serum samples, complete clot formation should take place before centrifugation.  Clotting time may be increased due to thrombolytic or anticoagulant therapy. 

Bilirubin is photosensitive.  Care should be taken to protect sample from both daylight and fluorescent light to avoid photodegradation.

Reference Range:  

Stability

Temperatures Period
Room Temperature 8 Hours
Refrigerated (2-8 ⁰C) 7 Days
Frozen (≤ -20 ⁰C) 6 Months

 

Use: Bilirubin levels are used to evaluate liver and biliary disease. As red blood cells normally age and breakdown, bilirubin (a by-product) is released into the blood causing the yellow pigment in serum. The liver normally clears bilirubin from the blood which is excreted in the bile. A small amount of bilirubin is normal, so low levels are generally not significant.
Clinical Significance: High bilirubin causes may include liver disease: hepatitis, cholangitis, cirrhosis, other types of liver disease (including primary or secondary neoplasia); alcoholism, biliary obstruction, infectious mononucleosis, Dubin-Johnson syndrome, Gilbert disease.
Anorexia or prolonged fasting: 36 hours or more may cause moderate rise.

Pernicious anemia, hemolytic anemias, erythroblastosis fetalis, other neonatal jaundice, hematoma, and following a blood transfusion, especially if several units are given in a short time.  Pulmonary embolism and/or infarct, congestive heart failure.

Drugs: A large number of drugs can cause jaundice by in vivo action or by chemistry methodology. Drugs causing cholestasis and/or hepatocellular damage include diphenylhydantoin, azathioprine, phenothiazines, erythromycin, penicillin, sulfonamides, oral contraceptives, anabolic-androgenic steroids, halothane, aminosalicylic acid, isoniazid, methyldopa, indomethacin, pyrazinamide, and others.

(High bilirubin summary) -  High bilirubin values may indicate a liver function problem, bile duct blockage, or excessive destruction of red blood cells.

Causes for Rejection: Gross hemolysis; improper labeling; gross lipemia