Reference Cards
Lab Differential Review
Total Bilirubin
(visible jaundice > 2.5-3.0 mg/dl, total bilirubin = direct + indirect fractions):
Normal Range: 0.2-1.5 mg/dI or 3-25 umol/l (SI)
Increased Total Bilirubin: Liver Biliary Tract Pathology (hepatitis, biliary obstruction [CBD stone, gallstone, stricture, atresia, cancer, surgical trauma, pancreatitis, metastases], cholestasis, cancer [primary, metastases], cirrhosis, sclerosing cholangitis), CHF hepatic congestion, sepsis, TPN, meds (halothane, oral contraceptives, allopurinol, antibiotics, steroids, INH, indocin, methyldopa, sulfonamides, tolbutamide, chloramphenicol, chlorpromazine), infectious mononucleosis, liver failure, hereditary pathology (Gilbert's )
Increased Direct Bilirubin (conjugated, water soluble, present in urine when elevated), > 0.3 mg/dl or 4 umol/l (SI): biliary obstruction (gallstone, CBD stone, pancreatitis, stricture, cancer [primary - hepatoma, pancreatic, ampullary, cholangiocarcinoma; metastases]), hepatitis (viral, drug, toxic), sepsis, TPN, biliary cirrhosis, alcoholic induced cirrhosis, Dubin Johnson syndrome, Rotor syndrome, Wilson's disease
Increased Indirect Bilirubin (unconjugated), > 1.0 mg/dl or 18 umol/l (SI): hemolysis, transfusion reaction, sickle cell anemia, hematoma reabsorption, hepatitis, cirrhosis, sepsis, CHF, cancer, liver failure, Gilbert's disease, Crigler-Najjar