INHERITED DISORDERS OF BILIRUBIN METABOLISM

Question 1

Unconjugated

Answer 1

GILBERT’S SYNDROME

Question 2

Bilirubin transport deficit; cant transport into
the hepatocyte

Answer 2

GILBERT’S SYNDROME

Question 3

Characterized by impaired cellular uptake of
bilirubin due to genetic mutation in UGT1A1
gene (chromosome #2)

Answer 3

GILBERT’S SYNDROME

Question 4

Affected individuals may have no symptoms but
may have mild icterus and predisposed
acetaminophen toxicity.

Answer 4

GILBERT’S SYNDROME

Question 5

GILBERT’S SYNDROME

Laboratory findings:

Indirect Bilirubin

Answer 5

1.5-3.0 mg/dL INCREASE

Question 6

Conjugation deficit

Answer 6

CRIGLER-NAJJAR SYNDROME

Question 7

CRIGLER-NAJJAR SYNDROME

Responsible for conjugation bilirubion

Answer 7

UDGPT

Question 8

Chronic non-hemolytic unconjugated
hyperbilirubinemia; Bilirubin 1 ; cant be
conjugated

Answer 8

CRIGLER-NAJJAR SYNDROME

Question 9

CRIGLER-NAJJAR SYNDROME

Laboratory result:

Answer 9

elevated indirect bilirubin

Question 10

CRIGLER-NAJJAR SYNDROM

Treatment:

Answer 10

phototherapy because they are
photo sensitive

Question 11

Complete deficiency of UDGPT

Answer 11

Crigler-Najjar Syndrome Type I

Question 12

Crigler-Najjar Syndrome Type I

Laboratory result:

Indirect bilirubin: ?
Direct bilirubin: ?

Answer 12

Indirect bilirubin: >25 mg/dL

Direct bilirubin: none

Question 13

Crigler-Najjar Syndrome Type I

Symptoms:

Answer 13

kernicterus, colorless bile

Question 14

Partial deficiency of UDGPT

Answer 14

Crigler-Najjar Syndrome Type II

Question 15

Crigler-Najjar Syndrome Type II

Laboratory results:

Answer 15

Indirect bilirubin: 5-20 mg/dL
direct bilirubin: small amount

Question 16

Familial form of unconjugated
hyperbilirubinemia caused by a circulating
inhibitor of bilirubin conjugation

Answer 16

LUCEY-DRISCOLL SYNDROME

Question 17

UDGPT is present but there is inhibitor present
which doesn’t not conjugate causing increase
indirect bilirubin.

Answer 17

LUCEY-DRISCOLL SYNDROME

Question 18

LUCEY-DRISCOLL SYNDROME

Laboratory findings:

Answer 18

Indirect bilirubin: increased (2-3 weeks of
life)

Question 19

CONJUGATED HYPERBILIRUBINEMIA

Answer 19

DUBIN-JOHNSON SYNDROME

Question 20

Bilirubin excretion deficit

Answer 20

DUBIN-JOHNSON SYNDROME

Question 21

Defective excretion of direct bilirubin into the
canaliculi caused by hepatocyte membrane
defect. B2

Answer 21

DUBIN-JOHNSON SYNDROME

Question 22

Characterized of an intense dark pigmentation
of the liver due to accumulation of LIPOFUSCIN
PIGMENT= black liver

Answer 22

DUBIN-JOHNSON SYNDROME

Question 23

CONJUGATED HYPERBILIRUBINEMIA

Answer 23

ROTOR SYNDROME

Question 24

Similar with dubin without the black liver

Answer 24

ROTOR SYNDROME

Question 25

The cause is unknown

Answer 25

ROTOR SYNDROME

Question 26

Rotor Syndrome

Laboratory findings:

Elevation in direct bilirubin and total bilirubin: ?

Delta Bilirubin: ?

Answer 26

Elevation in direct bilirubin and total bilirubin
(2-5mg/ dL)

Delta Bilirubin: increase

Question 27

Sample: SERUM ; covered with carbon paper or
aluminum foil

Answer 27

BILIRUBIN METHODOLOGY

Question 28

BILIRUBIN METHODOLOGY

If sample is prepared and stored properly:
o Room temperature: ?
o Refrigerator (4˚C): ?
o Freezer (-20˚C): ?

Answer 28

If sample is prepared and stored properly:
o Room temperature: 2 days
o Refrigerator (4˚C): 1 week
o Freezer (-20˚C): indefinite

Question 29

BILIRUBIN METHODOLOGY

Fasting sample is ________ but not required. Because Lipemia may cause false increased in bilirubin

Answer 29

preferred FASTING

Question 30

BILIRUBIN METHODOLOGY

Interferences:

decrease reaction of bilirubin with
diazo reagent (decreased bilirubin)

Answer 30

Hemolysis

Question 31

BILIRUBIN METHODOLOGY

Interferences:

increased bilirubin concentration

Answer 31

Lipemia

Question 32

diazotization
of bilirubin to form azobilirubin; indirect bilirubin
because it cant directly act on reagent

Answer 32

VAN DEN BERG REACTION

Question 33

to measure indirect bilirubin
because it is slow reacting bilirubin hence measured
total bilirubin.

Answer 33

Add accelerants

Question 34

Principle: Van den berg reaction

Answer 34

Evelyn and Malloy Method

Question 35

Reagents:

a.Coupling accelerator: ?
b. Diazo reagents: direct bilirubin

o Diazo A – ?
o Diazo B – ?
o Diazo blank – ?

Answer 35

Coupling accelerator: methanol
b. Diazo reagents: direct bilirubin
o Diazo A – 0.1% sulfanilic acid + HCL
o Diazo B – 0.5% sodium nitrate
o Diazo blank – 1.5% HCL

Question 36

Performed at pH near 1.0

Answer 36

Evelyn and Malloy Method

Question 37

Evelyn and Malloy Method

Final reaction:

Answer 37

PINK TO PURPLE (with maximal absorption at
560 nm

Question 38

Evelyn and Malloy Method

DISADVANTAGE:

Answer 38

The methanol will cause
precipitation in the sample which lead to turbidity
that interferes with the test.

Question 39

Most commonly used because it is more sensitive,
does not caused turbidity due to precipitation of
proteins. More safe much neutral Ph.

Answer 39

Jendrassik and Grof Method

Question 40

Popular technique for discreet analyzers

Answer 40

) Jendrassik and Grof Method

Question 41

Jendrassik and Grof Method

Main reagent:

Answer 41

Diazo reagent

Question 42

Jendrassik and Grof Method

Accelerator:

Answer 42

Caffeine sodium benzoate

Question 43

Jendrassik and Grof Method

Buffer:

Answer 43

sodium acetate

Question 44

jendrassik and Grof Method

terminates the accelerator and
destroys excess diazo reagent

Answer 44

ASCORBIC ACID

Question 45

Jendrassik and Grof Method

provides alkaline
pH after addition of ascorbic acid

Answer 45

ALKALINE TARTRATE SOLUTION

Question 46

Jendrassik and Grof Method

Final Reaction:

Answer 46

blue azobilirubin (measured at
600nm)