BILIRUBIN

Question 1

What is bilirubin?

Answer 1

A breakdown product of the porphyrin ring of heme

Question 2

How many fractions is bilirubin found in the blood?

Answer 2

2

Question 3

What are the two fractions of bilirubin found in the blood?

Answer 3

Conjugated (B2) and Unconjugated (B1)

Question 4

What is the alternative name for conjugated bilirubin?

Answer 4

Direct

Question 5

What is the alternative name for unconjugated bilirubin?

Answer 5

Indirect

Question 6

Who first described the reaction of bilirubin?

Answer 6

Ehrlich

Question 7

What reagent was used in Ehrlich’s description of the bilirubin reaction?

Answer 7

Diazotized sulfanilic acid

Question 8

What name was given to the type of reaction described by Ehrlich?

Answer 8

Diazo reaction

Question 9

What color pigment was formed in the diazo reaction?

Answer 9

Red-blue

Question 10

What did Van den Bergh find in 1913 regarding the diazo reaction?

Answer 10

It could be applied to serum samples with an accelerator or solubilizer

Question 11

What is the chief purpose of neonatal bilirubin quantitation?

Answer 11

To monitor diseases causing jaundice in the newborn

Question 12

What is another name for erythroblastosis fetalis?

Answer 12

Hemolytic disease of the newborn

Question 13

What is a common cause of hemolytic disease of the newborn (HDN)?

Answer 13

Maternal alloimmunization to RhD

Question 14

What is the average peak serum bilirubin concentration in a full-term newborn infant?

Answer 14

5 to 6 mg/dL

Question 15

At what serum bilirubin concentration range is physiologic jaundice seen?

Answer 15

7 to 17 mg/dL

Question 16

What term refers to the yellow staining of the basal ganglia due to severe jaundice?

Answer 16

Kernicterus

Question 17

Which condition is NOT listed as a cause of neonatal jaundice?

Answer 17

Diabetes

Question 18

Which type of bilirubin is water soluble?

Which type of bilirubin is found in urine?

Answer 18

Conjugated (Direct)

Question 19

Which type of bilirubin has a high molecular weight?

Which type of bilirubin gives an indirect Van den Bergh reaction?

Answer 19

Unconjugated (Indirect)

Question 20

Where is unconjugated (indirect) bilirubin normally found?

Answer 20

In plasma

Question 21

What is unconjugated (indirect) bilirubin attached to non-covalently?

Answer 21

Albumin

Question 22

Conjugated bilirubin is normally present in which location?

Answer 22

Bile

Question 23

What is the Van den Bergh Reaction?

Answer 23

A reaction between bilirubin and Ehrlich diazo reagent

Question 24

What is the color of the compound formed in the Van den Bergh Reaction?

Answer 24

Reddish purple

Question 25

What type of bilirubin reacts directly with Ehrlich diazo reagent?

Answer 25

Conjugated bilirubin

Question 26

What is conjugated bilirubin also known as?

Answer 26

Direct bilirubin

Question 27

When does unconjugated bilirubin react with Ehrlich diazo reagent?

Answer 27

After the addition of methyl alcohol

Question 28

What is unconjugated bilirubin also known as?

Answer 28

Indirect bilirubin

Question 29

Wahlefeld et al.

Answer 29

Detergent as accelerator

Question 30

What is the purpose of using a detergent in the Wahlefeld method?

Answer 30

To accelerate the reaction and avoid protein precipitation

Question 31

Under what conditions does DPD react with bilirubin?

Answer 31

Acidic

Question 32

What is the main component that DPD reacts with in the Wahlefeld method?

Answer 32

Bilirubin

Question 33

Van den Bergh

Answer 33

Serum

Question 34

What is the pH range of the acidic medium used in coupling total bilirubin with a diazonium salt?

Answer 34

1-2

Question 35

Which compound is coupled with total bilirubin in the Wahlefeld Method?

Answer 35

Diazonium salt (DPD)

Question 36

What is the main product formed when total bilirubin reacts with DPD?

Answer 36

Azobilirubin

Question 37

Malloy & Evelyn

Answer 37

50% methanol

Question 38

Within how many hours should samples kept at room temperature be analyzed?

Answer 38

Two hours

Question 39

How long can bilirubin in serum remain stable when stored frozen at -20°C?

Answer 39

Three months

Question 40

What is the effect of direct sunlight on bilirubin levels in the serum within one hour?

Answer 40

Decrease up to 50%

Question 41

Up to what concentration of serum triglycerides is considered non-interfering?

Answer 41

1000 mg/dl

Question 42

Which of the following is a mechanism of unconjugated hyperbilirubinemia?

Answer 42

Increased bilirubin production

Question 43

What can cause decreased liver uptake in relation to unconjugated hyperbilirubinemia?

Answer 43

Decreased liver uptake

Question 44

Which mechanism involves the liver's inability to properly process bilirubin resulting in unconjugated hyperbilirubinemia?

Answer 44

Decreased liver conjugation

Question 45

Decreased liver uptake results in:

Answer 45

Retention of unconjugated bilirubin

Question 46

What is the normal range for adults and infants older than 1 month?

Answer 46

0.2-1.0 mg/dl

Question 47

What is the expected blood content range for a full term newborn up to 24 hours?

Answer 47

2.0-6.0 mg/dl

Question 48

What are the expected blood values for infants up to 48 hours?

Answer 48

6.0-10.0 mg/dl

Question 49

What is the expected range of blood content in infants from 3 to 5 days?

Answer 49

4.0-8.0 mg/dl

Question 50

MAMA MO