Quick Review Cards for Medical Laboratory Science

Types of Bilirubin Clinical Chemistry Review 105

TYPE REFERENCE RANGE CLINICAL SIGNIFICANCE OTHER

Total bilirubin

Conjugated bilirubin

(direct bilirubin)

Unconjugated bilirubin

(indirect bilirubin)

0.2–1 mg/dL

<0.2 mg/dL

<0.8 mg/dL

↑liver disease, hemolysis,

hemolytic disease of newborn.

In infants, >20 mg/dL associ-

ated with brain damage

(kernicterus)

↑liver disease, obstructive

jaundice

↑prehepatic, posthepatic,

& some types of hepatic

jaundice

Sum of conjugated, unconjugated, & delta

bilirubin. Avoid hemolysis. Protect sample

from light. Jendrassik-Grof method. Diazo

reagent. Accelerator added so conjugated

bilirubin reacts. Bilirubinometry for

neonates only. Measures reflected light

from skin using 2 wavelengths.

Bilirubin monoglucuronide, bilirubin

diglucuronide, & delta bilirubin (bound to

albumin; only seen with significant hepatic

obstruction). Avoid hemolysis. Protect from

light. Jendrassik-Grof method. Diazo

reagent. No accelerator required.

Calculated value. Total bili – direct bili.

2956_Ch02_067-134 28/02/14 11:27 AM Page 105