Useful For

Total Bilirubin-Causes of high bilirubin:  Liver disease, hepatitis, cholangitis, cirrhosis, other types of liver disease (including primary or secondary neoplasia); alcoholism (usually with high AST, GGT, MCV or some combination of these findings); biliary obstruction (intrahepatic, extrahepatic); infectious mononucleosis
(look also for increased LDH, lymphocytosis).  Gilbert’s disease (familial hyperbilirubinemia) is encountered as a moderate elevation with otherwise unremarkable chemistries.  Dubin-Johnson Syndrome, Crigler-Najar Syndrome and Fructose Intolerance. 
Anorexia or prolonged fasting:  36 hours or more may cause moderate rise.  Pernicious anemia, hemolytic anemias, erythroblastosis fetalis, other neonatal jaundice, hematoma.

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 and pyrazinamide.
Direct Bilirubin-Yellow bile pigment is produced normally as a result of breakdown of aging red blood cell
hemoglobin.  Bilirubin is composed of two components – conjugated (“direct”) and unconjugated.  Increased
direct bilirubin occurs with biliary diseases, including both intrahepatic and extrahepatic lesions.  Hepatocellular causes of elevation include hepatitis, cirrhosis and advanced neoplastic states.  Increased with cholestatic drug reactions, Dubin-Johnson Syndrome and Rotor Syndrome.

LIMITATIONS:  Placental cord blood samples may yield elevated values.  Visibly hemolyzed samples
may yield spurious results.
CONTRAINDICATIONS:  Usually not necessary when the total bilirubin is normal.