Liver Function Test Flashcards
Perform majority function of liver;
Degenerative property of liver
Hepatocyte
Act as phagocyte
Kupffer cells
Line the sinusoid of the liver
Kupffer cells
Large organ divided unequally into 2 lobules by
Falciform ligament
Functional unit of the liver
Lobules
Chief metabolic organization
Liver
Responsible for all metabolic and excretory function of liver
Lobules
Amount of blood supply in the body
1500 ml/minute
Function of liver
- Synthetic function
- Conjugate function
- Detoxification and drug metabolism
- Excretory and secretory function
- Storage function
Ability to synthesize substance (protein)
Synthetic function
Metabolism of bilirubin
Conjugation function
Bile (elimination of cholesterol and bile salts)
Excretory and secretory function
Fat soluble
Vitamin A, D, E, K
Albumin + Globulin
Total protein
Sample used in total protein
Serum
Interference in total protein
Hemolysis and ictericia
Reference value for Total protein
6.5 - 8.3
Assessment of nutritional status and presence of diagnosis of disease involving kidney, liver and bone marrow
Total protein
Methods in total protein
- Kjeldahl
- Biuret
- Folin - Ciocalteu (lowry)
- UV absorption
- Refractometry
- Turbidimetry and Nephelometry
- Commasie brilliant blue dye
- Ninhydrin
- Serum protein electrophoresis
Classical method; reference but not routinely used
Kjeldahl
Colorimetric non enzyme method
Biuret
3 steps in kjeldahl method
Digestion
Distillation
Titration
Oxidation of phenolic compounds such as ___
Tyrosine, tryptophan & histidine
Principle: oxidation of phenolic compounds
Folin - ciocalteu (lowry) method
Based on refractive index of serum
Refractometry
Absorbance used in UV absorption method
210 nm
Absorption @ 280nm
Tryptophan, tyrosine & phenylalanine
Measures the amount of nitrogen
Kjeldahl
1g of nitrogen =
6.54 g of protein
Uniform fine precipitate which scatter lights or block of light
Nephelometry and turbidity
Detection of protein as little as 1 ug; disbonding technique
Coomasie brilliant blue dye
Color formed in biuret method
Deep purple / violet
Most widely used method for total protein
Biuret method
Biuret method absorbance
540 nm
Based on peptide bond present in protein with cupric ions
Biuret
Interference in biuret method
Lipemic
Reagents used in biuret method
Alkaline copper sulfite
Sodium potassium tartrate (rochelle salts)
NaOH
KI (stabilizer)
Color formed in Folin- ciocalteu
Deep blue
High analytical sensitivity
Folin-ciocalteu
Main reagent in folin
Phosphotungstic - molybdic acid/ phenol reagent
Folin color enhancer
Biuret reagent
Violet color reacting with primary amines widely used for detecting peptides and amino acids after paper chromatography
Ninhydrin
Either positive or negative
Amphoteric
Migration of charged particles in an electric field
SPE
SPE buffer
Barbital (veronal)
pH of buffer
6.8 (basic)
Reference value of albumin bond
3.5-5.0 g/dl (56-65%)
Reference value of a1 globulin
0.1-0.3 g/dl (2.5-5%)
Reference value of a2 globulin
0.6-1.0 g/dl (7-13%)
Reference value of beta globulin
0.7 - 1.1 g/dl (8-14%)
Gamma globulin reference value
0.8-1.6 g/dl (12-22%)
The concentration is directly proportional to the severity of hepatic disease
Albumin
Methods in albumin
Salt precipitation
Dye binding
Albumin is precipitated?
No. Globulin is precipitated
Albumin is quantitated using biuret reaction?
Yes
Binds to positive charge
Anionic dye
Dye commonly used
Bromocresol green
Most specific dye
Bromocresol purple
Not specific to albumin
Methyl orange
More specific to albumin
HABA - 2,4 - Hydroxyazobenzene - benzoic acid
Interference in dye binding
Conjugated bilirubin
Aspirin
Sulfonamides
Reference value of A/G ratio
1.3-3.1 g/dl
Formula of AG ratio
AG ratio = albumin / globulin
Globulin = total protein - albumin
Vitamin k response test
Prothrombin time
Amount administered in PT
10 mg for 1-3 days
It differentiate intrahepatic from extra hepatic disorder
PT
Prolonged PT
Intra hepatic
Not prolong PT
Extra hepatic