Liver Function Tests Flashcards
It is the largest internal organ of the body
Liver
A factor safety of x < 80% indicates?
normal liver function
A factor safety of x > 80% indicates?
abnormal liver function
Enumerate the 5 functions of liver.
- Metabolic
- Detoxification/conjugation
- Storage
- Excretory function
- Sythetic function
Give which liver function indicates the statement:
stores glycogen
storage
Give which liver function indicates the statement:
excretes bilirubin
excretory function
Give which liver function indicates the statement:
- molecular structure is altered
- toxic to non-toxic
- protection
detoxification/conjugation
Give which liver function indicates the statement:
protein synthesis
synthetic function
Give the 4 substances that the liver does not produce.
- antibodies
- y-globulins
- immunoglobulins
- Von Willebrand factor
Detoxification/Conjugation Assessment
sodium benzoate is ingested and converted into benzoic acid
Quick’s/Hippuric Acid Test
bilirubin in urine
urobilin
bilirubin in stool
stercobilin
Detoxification/Conjugation Assessment
In Quick’s/Hippuric Acid Test, benzoic acid conjugates with ____ to produce ____.
- glycine
- hippuric acid
Detoxification/Conjugation Assessment
In Quick’s test, urine is titrated with ___.
standard NaOH
Excretory Assessment
Bilirubin profile is part of ___.
Screening test
Excretory Assessment
Bilirubin profile determines what type of bilirubin?
- conjugated bilirubin
- unconjugated bilirubin
- total bilirubin
Excretory Assessment
It is the confirmatory test.
Bromsulphthalein Test
Excretory Assessment
The solution intravenously injected to the patient in Bromsulphthalein test.
5 mL of 5% BSP dye
Excretory Assessment
Intrepret the results of BSP Test:
colorless serum blood: _____
red serum blood: _______
colorless serum blood: absent BSP (normal)
red serum blood: present BSP (hepatic insufficiency)
Sources of Bilirubin
- 90% (due to RBC destruction):
- 5%:
- 5%:
- hemoglobin degradation
- myoglobin degradation
- cytochrome
Types of Bilirubin
first bilirubin produced
unconjugated
Types of Bilirubin
Unconjugated Bilirubin
main product of RBC destruction
hemobilirubin
Types of Bilirubin
Unconjugated Bilirubin
insoluble in water
nonpolar bilirubin
Types of Bilirubin
Unconjugated Bilirubin
coated with albumin
indirect bilirubin
Types of Bilirubin
Unconjugated Bilirubin
deposited in the brain
kernicterus bilirubin
Types of Bilirubin
Unconjugated Bilirubin
deposited in the CSF
icterus bilirubin
Types of Bilirubin
Unconjugated Bilirubin
xanthochromia
icterus bilirubin
Types of Bilirubin
Unconjugated Bilirubin
not yet excreted by the liver
pre-hepatic bilirubin
Types of Bilirubin
Conjugated Bilirubin
soluble in water
polar bilirubin
Types of Bilirubin
Conjugated Bilirubin
no albumin coating
direct bilirubin
Types of Bilirubin
Conjugated Bilirubin
excreted by the liver
post hepatic bilirubin
Types of Bilirubin
Conjugated Bilirubin
reason why stool is brown
stercobilinogen
Types of Bilirubin
Conjugated Bilirubin
- reason why urine is yellowish
- pigment
- excess conjugated bilirubin
urobilin
Unconjugated Bilirubin Production
RBC explodes in the sinusoidal spaces of the spleen, hemoglobin is release into the plasma
Hemoglobin fragmentation
Unconjugated Bilirubin Production
- abundant in Hb
- stored as ferritin
- transported by transferrin
iron
Unconjugated Bilirubin Production
Transferrin is also known as?
siderophilin
Unconjugated Bilirubin Production
- protein component of Hb
- hydrolyzed into amino acids
- used to build new proteins
globin
Unconjugated Bilirubin Production
- broken into biliverdin
- reduced by biliverdin reductase to form unconjugated bilirubin
porphyrin ring
Unconjugated Bilirubin Production
conjugation occurs at ____
Smooth ER
Unconjugated Bilirubin Production
Bilirubin will mix with ___(1)___. It is broken by ___(2)___ to create __(3)__ & __(4)__.
- glucuronic acid
- uridine diphosphate glucuronyltransferase (UDP GT)
- B1 (bilirubin monoglucuronide)
- B2 (bilirubin diglucuronide)
Unconjugated Bilirubin Production
incomplete conjugation: _____
complete conjugation: ______
incomplete conjugation: B1 (bilirubin moglucuronide)
complete conjugation: B2 (bilirubin diglucuronide)
Unconjugated Bilirubin Production
- 1:1 ratio
- remains in the liver for conjugation to be completed
B1 (bilirubin monoglucuronide)
Unconjugated Bilirubin Production
- 1:2 ratio
- excreted by the liver
B2 (bilirubin diglucuronide)
- excess bilirubin in the blood
- yellowish discoloration
jaundice
True or False:
Bilirubin is photosensitive
True
True or False:
Test specimen must be placed in amber glass bottle.
False
*Test tube must be protected with aluminum foil or carbon paper
Bilirubin Measurement
- color reaction for bilirubin
- fast reaction
Van den Bergh reaction
Bilirubin Measurement
DSA stands for?
diazotized sulfanilic acid
Bilirubin Measurement
How is nitrous acid formed?
sodium nitrite + HCl
Bilirubin Measurement
What reaction involves the ff:
serum + DSA → azobilirubin
Van den Bergh reaction
Bilirubin Measurement
- one-step method
- fast reaction
- measures conjugated bilirubin only
Direct VDB Method
Bilirubin Measurement
serum with conjugated bilirubin + Ehrlich’s DSA → azobilirubin
Direct VDB Method
Bilirubin Measurement
measures total bilirubin (conjugated + unconjugated)
Indirect VDB Method
Bilirubin Measurement
Indirect VDB:
Caffeine Sodium Benzoate
Jendrassik-Grof
Bilirubin Measurement
Indirect VDB:
modified method
diphyllin
Bilirubin Measurement
- rough measurement of bilirubin content in the serum
- HDN
icterus index
Icterus Index
standard used
diluted potassium dichromate (K2Cr2O7)
Icterus Index
Interpret/advise the following if the indicated tubes have the same color:
- 1st-3rd tubes:
- 4th-5th tubes:
- 6th-10th tubes:
- 1st-3rd tubes: exchange blood transfusion
- 4th-5th tubes: phototherapy
- 6th-10th tubes: normal
Jaundice
- excessive RBC degradation
- fast turnover of RBC
hemolytic jaundice
Jaundice
- presence of gallstones and biliary stones
obstructive jaundice
Jaundice
hapatocellular jaundice is also known as ____
hepatogenous jaundice
Jaundice
- liver dysfunction
- due to hepatitis, cirrhosis, cancer
- conjugation & excretion is very slow
hepatocellular jaundice
Interpret the following bilirubin measurements
conjugated bilirubin: normal
unconjugated bilirubin: elevated
total bilirubin: elevated
hemolytic anemia
Interpret the following bilirubin measurements
conjugated bilirubin: elevated
unconjugated bilirubin: normal
total bilirubin: elevated
obstructive anemia
Interpret the following bilirubin measurements
conjugated bilirubin: elevated
unconjugated bilirubin: elevated
total bilirubin: elevated
hepatocellular jaundice
Metabolism
Normal transport of bilirubin in the entire liver tissue requires?
*There are two.
ligandin & z-protein
Metabolism
Adequate enzyme (UDP-GT) to be conjugated in the liver. How do you produce UDP-GT?
bilirubin + glucuronic acid
Abnormal Metabolism
defective bilirubin transport
Gilbert Syndrome
Abnormal Metabolism
deficient ligandin & z-protein
*cannot transport 1 hepatocyte to another
Gilbert Syndrome
Abnormal Metabolism
elevated unconjugated bilirubin = ______
elevated unconjugated bilirubin = slow conjugation
Abnormal Metabolism
Give 2 syndromes that have high unconjugated bilirubin/slow conjugation.
- Gilbert Syndrome
- Crigler Najjar Syndrome
Abnormal Metabolism
- deffective bilirubin conjugation
- deficient conjugating UDP-GT
Crigler Najjar Syndrome
Abnormal Metabolism
- defective excretion due to canalicular damage
Dubin Johnson Syndrome
Abnormal Metabolism
elevated conjugated = ______
elevated conjugated = slow excretion
Abnormal Metabolism
Give 2 syndromes that have slow excretions or high conjugated bilirubin.
- Dubin Johnson Syndrome
- Rotor Syndrome
Abnormal Metabolism
defective excretion due to an obstruction in billiary passages caused by a viral infection
Rotor Syndrome
used to monitor hepatic coma
ammonia
__(1)__ need to be converted to urea with the help of __(2)__.
- ammonia
- ornithine carbamyl transferase (OCT)
detected in the amniotic fluid of pregnant women
alpha-1 fetoprotein (AFP)
True or False & follow ups:
alpha1 globulin is normally present in the fetus.
Is it normal for adults to have a1 globulin?
True
If present in adults, hepatoma is present (liver cancer).
If alpha 1 fetorpotein is above reference range what happens?
If it is below reference range?
above ref range: Hemolytic Tube/Neural Tube defect (fetus brain is outside the skull)
below ref range: Down Syndrome