Liver Functions Prt. 2 Flashcards
1
Q
JAUNDICE
• From the french word____ which means “yellow”
A
jaune
2
Q
One of the oldest known pathologic conditions reported & described by Hippocratic physicians
A
Jaundice
3
Q
Jaundice
• Yellowish discoloration of the (3).
• Due to the retention of____
• May also occur due to the retention of other substances
A
skin, eyes and mucous membranes
bilirubin
4
Q
The normal level of bilirubin is
A
0.2-1.0 mg/dL
5
Q
Jaundice will only become overt or noticeable to the naked eye at above____
A
3.0 mg/dL.
6
Q
_______- term used in the laboratory to refer to a serum or plasma with a yellowish discoloration due to bilirubin.
• Dark yellow discoloration of serum/plasma
• Yellow serum will stay in the walls of the test tube once tilted
• Will have effects in other test results
A
Icterus
7
Q
Total Bilirubin Upper Limit -
A
1.0 to 1.5 mg/dL
8
Q
Overt Jaundice - Not noticeable by the naked eye until it reaches
A
3.0 to 5.0 mg/dL
9
Q
Normal
Noticeable
TB upper limit
Overt jaundice
A
0.2-1.0 mg/dL
3.0 mg/dL.
1.0 to 1.5 mg/dL
3.0 to 5.0 mg/dL
10
Q
Liver function test based upon bile pigment metabolism
A
licteric index
11
Q
Icteric serum
[Bilirubin concentration)
1+=
2+ =
3+=
4 =
A
2.5 mg/dL
5.0 mg/dL
10.0 mg/dL
20.0 mo/dL
12
Q
TYPES OF JAUNDICE
A
Pre-Hepatic
Hepatic
Post-Hepatic
13
Q
• Excessive amount of bilirubin is presented to the liver due to excessive hemolysis.
• Excessive amount of bilirubin is presented to the liver for metabolism
Due to processes/diseases before conjugation in the liver
A
PRE-HEPATIC JAUNDICE
14
Q
Elevated unconjugated bilirubin (B1) in serum.
A
PRE-HEPATIC JAUNDICE
15
Q
Hemolysis, Hemolytic Anemia, Malaria
Increased breakdown of RBCs
Increased conjugated bilirubin in the blood = unconjugated hyperbilirubinemia
A
PRE-HEPATIC JAUNDICE
16
Q
• Impaired cellular uptake, defective conjugation or abnormal secretion by the liver cell (= intrinsic liver defect/diseases)
A
HEPATIC JAUNDICE
17
Q
Both conjugated and unconjugated bilirubin may be elevated in serum.
A
HEPATIC JAUNDICE
18
Q
- Increased B1
A
Unconjugated Hyperbilirubinemia
19
Q
Unconjugated Hyperbilirubinemia (2)
A
Gilbert Syndrome
Crigler-Najjar Syndrome
20
Q
Gilbert Syndrome -› Benign autosomal recessive hereditary disorder
Genetic mutation of _____
A
UGT1A1 = UDP Glucuronosyltransferase
Family 1 Member A1
21
Q
Gene that encodes the
UDPGT enzyme = can’t
conjugate B1 to B2
A
UGT1A1
uridine diphosphate glucuronosyltransferase 1A1 gene (UGT1A1)
22
Q
- Elevated B1
- 30% of the liver is still functional = some conjugation may still be possible
- May have no symptoms but w/ mild icterus
A
Gilbert Syndrome
23
Q
- More serious than Gilbert syndrome
A
Crigler-Najjar Syndrome
24
Q
Crigler-Najjar Syndrome
Deficiency of _____ enzyme
A
uridine diphosphate-glucuronosyltransferase (UDPGT)
25
-
Complete absence of UDPGT
Accumulation of bilirubin in the brain = neuronal degeneration = Kernicterus
<1 year life expectancy
Some may reach 1 year = phototherapy
Crigler-Najjar Syndrome Type 1
26
Severe/partial deficiency of UDPGT = decreased B2
• Px. can still survive w/ phototherapy
Crigler-Najjar Syndrome Type 2
27
UV rays can oxidize bilirubin to_____
If bilirubin is exposed to light = falsely decreased = must be covered upon testing
biliverdin
28
- Increased B2
Conjugated Hyperbilirubinemia
29
Conjugated Hyperbilirubinemia (2)
Dubin-Johnson Syndrome
Rotor's Syndrome
30
-› Autosomal recessive disease
• Presents shortly after birth
Increased B2 w/o elevation of liver
enzymes (ALT & AST) = can also
see Delta Bilirubin
Dubin-Johnson Syndrome
31
Defective excretion of bilirubin by
hepatocytes to bile canal = B2
returns to bloodstream
Deficiency in______
Dubin-Johnson Syndrome
canalicular multidrug resistance/multispecific organic anionic transporter protein (MDR2/cMOAT)
32
- Liver granules aren't pigmented = liver biopsy
- Increased B2
• Unknown etiology w/ good prognosis
Rotor's Syndrome
33
Same symptoms w/ Dubin-Johnson Syndrome
> Differentiated through liver
biopsy = absence of liver granules
Rotor's Syndrome
34
T or F
Physiologic Jaundice of the Newborn - Newborn
Jaundice is normal
True
35
Physiologic Jaundice of the Newborn
Deficiency of _____= last enzyme to be fully developed = liver isn't fully developed
UDPGT
36
- Bilirubin-conjugation inhibition
Lucey-Driscoll Syndrome
37
Lucey-Driscoll Syndrome
AKA
Transient Familial Neonatal
Hyperbilirubinemia
38
Circulating inhibitor of bilirubin conjugation
Increase of B1 = can't be conjugated
Lucey-Driscoll Syndrome
39
• Impaired bilirubin excretion due to mechanical obstruction to bile flow.
Due to processes/diseases after conjugation in the liver
POST-HEPATIC JAUNDICE
40
Elevated conjugated bilirubin (B2) in serum.
POST HEPATIC JAUNDICE
41
Biliary Obstructive Diseases - Gallstones, Tumor
Increased conjugated bilirubin in the blood
Can't be fully excreted to the
feces/urine = goes back to the
bloodstream
POST HEPATIC JAUNDICE
42
Slightly increased unconjugated bilirubin = lesser than B2
Duct obstruction = buildup of
pressure = liver injury = impaired
conjugation function
Not all B1 will be converted to B2
POST HEPATIC JAUNDICE
43
It is most commonly caused by an ***increased amount of bilirubin*** being presented to the liver such as that seen in acute and chronic hemolytic anemias.
occurs when the problem causing the jaundice occurs prior to liver metabolism.
Prehepatic jaundice
44
Other term for pre hepatic jaundice
_______ because the fraction of bilirubin increased in people with prehepatic jaundice is the unconjugated fraction.
unconjugated hyperbilirubinemia
45
are hepatic causes of jaundice that result in elevations in ***unconjugated bilirubin.***
Gilbert's disease
Crigler-Najjar syndrome
physiologic jaundice of the newborn
46
Conditions such as _____ and_____ are hepatic causes of jaundice that result in elevations in conjugated bilirubin.
Dubin-Johnson
Rotor's syndrome
47
________, first described in the early twentieth century, is a benign autosomal recessive hereditary disorder that affects approximately 5% of the US population.
Gilbert's syndrome
48
Gilbert's syndrome results from a genetic mutation in the______ gene that produces the enzyme_______ important for bilirubin metabolism.
The UGT1A1 gene is located on chromosome 2, and other mutations of this same gene produce Crigler-Najjar syndrome, a more severe and dangerous form of hyperbilirubinemia.
UGT1A1
uridine diphosphate glucuronosyltransferase
49
occurs when the problem causing the jaundice occurs prior to liver metabolism.
It is most commonly caused by an increased amount of bilirubin being presented to the liver such as that seen in acute and chronic hemolytic anemias.
Prehepatic jaundice
50
The liver responds by functioning at maximum capacity; therefore, people with______ rarely have bilirubin levels that exceed 5.0 mg/dL because the liver is capable of handling the overload.
prehepatic jaundice
51
This type of jaundice may also be referred to as________ because the fraction of bilirubin increased in people with prehepatic jaundice is the unconjugated fraction.
unconjugated hyperbilirubinemia
52
is not water soluble, is bound to albumin, is not filtered by the kidneys, and is not seen in the urine.
unconjugated bilirubin
53
Type of jaundice
intrinsic liver defect or disease
Hepatic
54
Hepatic jaundice
Crigler-Najjar syndrome
Dubin-Johnson syndrome
Gilbert's disease
neonatal physiologic jaundice of the newborn
55
(3) are hepatic causes of jaundice that result in elevations in ***unconjugated bilirubin.***
Gilbert's disease
Crigler-Najjar syndrome
physiologic jaundice of the newborn
56
Conditions such as _____ and_____ are hepatic causes of jaundice that result in elevations in ***conjugated bilirubin.***
Dubin-Johnson
Rotor's syndrome
57
Gilbert's syndrome results from a genetic mutation in the______ gene that produces the enzyme UDPGT — uridine diphosphate glucuronosyltransferase, one of the enzymes important for bilirubin metabolism.
UGT1A1
58
The UGT1A1 gene is located on chromosome 2, and other mutations of this same gene produce_______ syndrome, a more severe and dangerous form of hyperbilirubinemia.
Crigler-Najjar syndrome
59
Of the many causes of jaundice,______ is the most common cause, and interestingly, it carries no morbidity or mortality in the majority of those affected and carries generally no clinical consequences.
It is characterized by ***intermittent unconjugated hyperbilirubinemia,*** underlying liver disease due to a defective conjugation system in the absence of hemolysis.
Gilbert's syndrome
60
Crigler-Najjar syndrome may be divided into two types:
type 1, where there is a ______ of enzymatic bilirubin conjugation
type II, where there is a______ causing a severe_____ of the enzyme responsible for bilirubin conjugation.
complete absence
mutation; deficiency
61
Unlike Gilbert's syndrome,______ is rare and is a more serious disorder that may result in death.
Crigler-Najjar syndrome
62
Dubin-Johnson syndrome and Rotor's syndrome are characterized as_______
conjugated hyperbilirubinemias
63
is a rare autosomal recessive inherited disorder caused by a deficiency of the ***canalicular multidrug resistance/multispecific organic anionic transporter protein (MDR2/cMOAT).***
In other words, the liver's ability to uptake and conjugate bilirubin is ***functional;*** however, the removal of conjugated bilirubin from the liver cell and the excretion into the bile are ***defective.***
This results in accumulation of conjugated and, to some extent, unconjugated bilirubin in the blood, leading to ***hyperbilirubinemia and bilirubinuria.***
DubinJohnson syndrome
64
______ is a condition that is obstructive in nature, so much of the conjugated bilirubin circulates bound to albumin.
This type of bilirubin (conjugated bilirubin bound to albumin) is referred to as_____.
Dubin-Johnson
delta bilirubin
65
reacts as conjugated bilirubin in the laboratory method to measure conjugated or direct bilirubin.
delta bilirubin
66
A distinguishing feature of_______ syndrome is the appearance of______ (thought to be pigmented lysosomes) on a liver biopsy sample.
have a normal life expectancy, so no treatment is necessary.
Dubin-Johnson
dark-stained granules
67
T or F
the defect causing Rotor's syndrome is not known
True
68
Physiologic jaundice of the newborn is a result of a deficiency in the enzyme_____, one of the last liver functions to be activated in prenatal life since bilirubin processing is handled by the mother of the fetus.
Premature infants may be born without ____, the enzyme responsible for bilirubin conjugation.
UDPGT
69
UDPGT deficiency results in the rapid buildup of unconjugated bilirubin, which can be life threatening.
When unconjugated bilirubin builds up in the neonate, it cannot be processed and it is deposited in the nuclei of brain and degenerate nerve cells, causing______.
kernicterus
70
Infants with this type of jaundice are usually treated with_____ to destroy the bilirubin as it passes through the capillaries of the skin.
It lowers serum bilirubin levels by using____ or ____ lights to transform bilirubin into watersoluble isomers that can be eliminated without conjugation in the liver.
During this process, the baby is undressed so that as much of the skin as possible is exposed to the light, his/her eyes are covered to protect the nerve layer at the back of the eye (retina) from the bright light, and the bilirubin levels are measured at least once a day.
phototherapy
halogen or fluorescent
71
results from biliary obstructive disease, usually from physical obstructions (gallstones or tumors) that prevent the flow of conjugated bilirubin into the bile canaliculi.
Posthepatic jaundice
72
the liver cell itself is functioning, bilirubin is effectively conjugated; however, it is unable to be properly excreted from the liver.
Since bile is not being brought to the intestines, stool loses its source of normal pigmentation and becomes clay-colored.
Post hepatic jaundice
