HyperBilirubinaemia

Question 1

process of bilirubin synthesis

Answer 1

• globin removed from HB to form haeme
  -haeme acted on by HAEME OXIDASE to form Biliverdin
• reduced by BILIVERDIN REDUCTASE to form Bilirubin
• transported to liver & conjugated there

Question 2

what level of bilirubin is described as hyperbilirubinaemia

Answer 2

above 1.5mg/dl (25.5umol/L)

Question 3

when does jaundice occur in hyperbilirubinaemia

Answer 3

above 2.0mg/dl (34umol/L)

Question 4

Pathophysiology of Hyperbilirubinaemia

Answer 4

1) increased RBC destruction
2) hepatic uptake disorder
3) drug displacement of bilirubin from binding sites
4) hepatic conjugation disorder
5) interference with albumin transport

Question 5

__ hydrolyses conjugated bilirubin and increases its absorption

Answer 5

beta-glucoronidase in meconium

Question 6

which type of hyperbilirubinaemia is Indirected?

Answer 6

unconjugated

Question 7

in unconjugated hyperbilirubinaemia, bilirubin is found in the urine,
True/False ?

Answer 7

false !

*it is lipid soluble but not water soluble

Question 8

where does bilirubin deposit in unconjugated hyperbilirubinaemia?

Answer 8

the basal ganglia & brain stem

Question 9

__ has been added to bilirubin to conjugate it in conjugated hyperbilirubinaemia ?

Answer 9

glucoronic acid

Question 10

Breast milk jaundice is due to the presence of _ in milk

Answer 10

alpha - glucoronidase

Question 11

types of UN-HYPERB

Answer 11

1) physiological jaundice
2) breast milk jaundice
3) haemolytic disorders eg G6PD deficiency
4) haemoglobinopathies eg Thalassemia
5) inherited syndrome eg Gilbert, Crigler Najjar, Lucey Driscoll

Question 12

UN-HyperB occurs when there sis a problem _ of conjugation.

Answer 12

upstream

Question 13

what happens to urobilinogen in UN-HyperB

Answer 13

its level is increased in urine

Question 14

_ is the most common congenital cause of UN-HYPERB

Answer 14

Gilbert’s syndrome

Question 15

Gilbert’s syndrome is caused by a mutation of what gene ?

Answer 15

UGT1A1 gene (leads to reduced activity of glucuronosyltransferase)

*helps process bilirubin

Question 16

in type 1 of Crigler-Najjar Syndrome there is deficiency of what enzyme ?

Answer 16

uridyl-diphosphoglucuronyl transferase
(UDPGT)

Question 17

_ type of Crigler-Najjar syndrome responds to phenobarbital treatment

Answer 17

type 2 (there’s partial deficiency of UDPGT)

Question 18

what syndrome has a circulating inhibitor of bilirubin conjugation ?

Answer 18

Lucey -Driscoll syndrome
(*familial)

Question 19

extrahepatic causes

Answer 19

1) stones
2) infection
3) tumors
4) compression of biliary duct
5) primary sclerosing cholangitis

Question 20

intrahepatic causes

Answer 20

1) familial/hereditary disorders
2) drugs
3) sepsis
4) post op state
5) biliary cirrhosis
6) hepatocellular disease
7) neoplasms

Question 21

what is bilirubin level in physiological neonatal jaundice

Answer 21

Less than 15mg/dl

Question 22

what happens to unconjugated bilirubin levels in PREHEPATIC jaundice

Answer 22

it is ELEVATED

Question 23

Unconjugated bilirubin is NOT present in any type of jaundice

Answer 23

TRUE

Question 24

in what forms of jaundice are conjugated bilirubin levels elevated in the blood & urine

Answer 24

hepatic & post hepatic

Question 25

Urobilinogen is elevated in Urine & faeces in what type of jaundice

Answer 25

pre hepatic

*levels normal in hepatic & absent in post hepatic

Question 26

when AST & ALT are elevated it is most likely what type of jaundice ?

Answer 26

hepatic

Question 27

ALP is elevated in what type of jaundice ?

Answer 27

post hepatic

Question 28

Jendrassik-Groff uses _ as an accelerator
while methanol is used as an accelerator in _

Answer 28

caffeine
Malloy-Evelyn

*Diazo reaction

Question 29

Enzymatic method uses _

Answer 29

bilirubin oxidase

Question 30

component of fouchets reagent

Answer 30

1) trichloroacetic acid - 25gms
2) distilled water -100ml
3) 10% ferric chloride solution - 10ml

*add 10% barium chloride to acidified urine
* 1 drop of Fouchets
*blue/green indicates bilirubin

Question 31

colorimetric strip raegent test is based on what principle ? i

Answer 31

coupling of bilirubin with diazotized 2,4-dichloroaniline in a strong ACID medium to form a brown/purple azobilirubin compound

*results - negative, small(+), moderate (++), large (+++)

Question 32

what test is used for detection of urobilinogen ?

Answer 32

Qualitative Ehrlich’s Test

Question 33

components of Ehrlich’s reagent

Answer 33

paradimethylaminobenzaldehyde

20% 5HCL

*pink color if urobilinogen is present
*cherry red if excess
*use fresh urine, exposure to air oxidizes urobilinogen to urobilin

Question 34

test for detection of bile salts

Answer 34

• hay test

*sprinkle flowers of sulphur in urine
*if bile salts present they sink to the bottom (bile salts lower surface tension)

Question 35

test for detection of bile pigments

Answer 35

1) foam test (yellow foam indicates bile pigments)
2) Gmelins test
*yellow nitric acid in test tube with urine
*play of colored rings, most distinct being green indicates bile pigments

Question 36

de ritis ratio

Answer 36

ratio of AST/ALT (used to differentiate btwn viral & non viral hepatitis)

<1 = viral hepatitis
>1= non viral hepatitis (alcohol liver dx usu >3)

Question 37

AST & ALT levels in acute liver disease vs chronic liver disease

Answer 37

both elevated in acute
AST higher in chronic

*AST in cytosol & mitochondria
*ALT in only cytosol

Question 38

type 1 Crigler Najjar syndrome is what

Answer 38

autosomal recessive

Question 39

type 11 crigler najjar syndrome is

Answer 39

autosomal dominant