Liver Function Tests Flashcards
Receives 15 mL of blood per minute
Liver
: anatomic unit
Lobule
Synthetic function
Proteins, CHO, lipids, LPP, clotting factors, ketone bodies, enzymes
Albumin:
12g/day
Conjugation function
Bilirubin metabolism
Bilirubin:
200mg/day
Detoxification and Drug metabolism
Drugs
Ammonia Urea Excreted
Excretory and Secretory functions
Bile acids:
Bile salts:
cholic acid and chenodeoxycholic acid
bile acids + amino acids (glycine and taurine)
Storage function
Vitamins
Glycogen
Test measuring the Hepatic Synthetic Ability
Total Protein Determination
Prothrombin Time (Vitamin K Response Test)
Total Protein Determination:
-Kjeldahl method
-Biuret method
-Folin-Ciocalteu (Lowry) method
-UV absorption method
-Electrophoresis
-Refractometry
-Turbidimetric and Nephelometric methods
-Salt fractionation
Test measuring Conjugation/Excretion Function
Bilirubin Assay
Bromsulfonphthalein (BSP) Dye Excretion test
Bilirubin Assay:
-Evelyn and Malloy method
-Jendrassik and Grof Bromsulfonphthalein (BSP) Dye Excretion test
Test for Detoxification Function
Enzyme tests:
Ammonia:
ALP, AST, ALT, 5’NT, GGT, OCT, LAP, LDH
-Kjeldahl (Digestion) method -Nesslerization reaction -Berthelot reaction
0.2-0.4 g/dL higher than serum due to fibrinogen
Plasma protein
AMMONIA: Standard reference method
Kjeldahl (Digestion) mtd
Measurement of nitrogen content
Kjeldahl (Digestion) mtd
Serum + Tungstic acid PFF
Kjeldahl (Digestion) mtd
1g N2 = 6.54g protein
Kjeldahl (Digestion) mtd
15.1-16.8% = N2 content of proteins
Kjeldahl (Digestion) mtd
Kjeldahl (Digestion) mtd Rgt:
H2SO4
Kjeldahl (Digestion) mtd
End product:
NH3
Most widely used method (IFCC recommended)
Biuret method
Req. at least 2 peptide bonds and an alkaline medium
Biuret method
Biuret method Rgts:
Alkaline CuSO4
Rochelle salt (NaK Tartrate)
NaOH
KI
Biuret method End product:
Violet color (545nm)
Highest analytical sensitivity
Folin-Ciocalteu (Lowry) method
Oxidation of phenolic compounds (tyrosine, tryptophan, histidine)
Folin-Ciocalteu (Lowry) method
Folin-Ciocalteu (Lowry) method Rgts:
Phenol (or phosphotungstic-molybdic acid)
Biuret (color enhancer)
Folin-Ciocalteu (Lowry) method End product:
Blue color
MI: elevated APRs (AAT, HPG, a1-x)
Electrophoresis
Gamma-spike
Monoclonal gammopathy (multiple myeloma)
Beta-gamma bridging
In serum:
In plasma:
Hepatic cirrhosis (IgA)
normal (fibrinogen)
Alpha2-globulin band spike
Nephrotic syndrome
Alpha1-globulin flat curve
Juvenile cirrhosis (AAT deficiency)
Alpha1, alpha2, betaglobulin band spikes
Inflammation
Polyclonal gammopathy
Chronic inflammation (RA, malignancy)
Small spikes in beta region
IDA (transferrin)
“Blip” in the late alpha2 or early beta region
Free hemoglobin
Refractive index
Refractometry
Turbidimetric and nephelometric methods
SSA
TCA
Salt fractionation
Salt: Sodium sulfate
Albumin
Soluble:
Insoluble:
Water
Moderately concentrated salt solution
Concentrated salt solution
Hydrocarbon solvents
Highly concentrated salt solution
Saturated salt solution
Globulin
Soluble:
Insoluble:
Hydrocarbon solvents
Weak salt solution
Water Saturated salt solution
Concentrated salt solution
Differentiates intrahepatic disorder (prolonged PT) from extrahepatic obstructive liver disease (normal PT)
Prothrombin time
Inversely proportional to the severity of the liver disease
Albumin
Low total protein + low albumin
Hepatic cirrhosis
Most commonly used dye for albumin
Bromcresol green
Most specific dye for albumin
Bromcresol purple