Liver Function TestLiver Function Testss

รองศาสตราจารย์แพทย์หญิ�งพรรธนมณฑน อ�ชรองศาสตราจารย์แพทย์หญิ�งพรรธนมณฑน อ�ชช�นช�น

ภาควิ�ชาเวิชศาสตรช�นส�ตร คณะภาควิ�ชาเวิชศาสตรช�นส�ตร คณะแพทย์ศาสตรแพทย์ศาสตร

จ�ฬาลงกรณมหาวิ�ทย์าล�ย์จ�ฬาลงกรณมหาวิ�ทย์าล�ย์

วิ�ตถุ�ประสงค วิ�ตถุ�ประสงค : : หล�งจากเสร%จส�&นการหล�งจากเสร%จส�&นการเร'ย์น น�ส�ตสามารถุเร'ย์น น�ส�ตสามารถุ

1 . อธ�บาย์ล�กษณะท�*วิไปของต�บ2. เข-าใจหน-าท'*ส/าค�ญิของต�บ(Major Functions of

the Liver) 3. แย์กชน�ดและอธ�บาย์การเก�ด Jaundice ชน�ดต1างๆ

ในร1างกาย์ 4. เข-าใจ Pathway of Bilirubin

5. ร�-จ�กInherited Disorders of Bilirubin Metabolism

6. ร�-จ�กชน�ดต1างๆของ LFTs7. เข-าใจหล�กการและแปลผล routine LFTs ท'*เล4อกได-8. อธ�บาย์สาเหต�และเล4อกใช- LFTs ท'*เหมาะสมส/าหร�บโรค

ต�บและทางเด�นน/&าด'ท'*พบบ1อย์ๆได-9. แปลผล LFTs ท'*เล4อกใช-ได-

LIVERLIVER

Blood supply 1515 ml/min : Portal vein, Hepatic artery Parenchymal cells : Hepatocyte Nonparenchymal cells : Endothelial cells Kupffer cells Hepatic stellate cells Pit cellsHypoglycemia

Major Functions of the LiverMajor Functions of the Liver1. Synthesis and metabolism of

proteins,carbohydrates and lipids

2. Production, metabolism and excretion of bile

3. Detoxification and drug metabolism

4. Enzymes synthesis

5. Storage of vitamins and minerals

6. Biotransformation or Inactivation of hormones

7. Phagocytosis

Synthesis & metabolism Synthesis & metabolism of of

proteins,carbohydrates and fatsproteins,carbohydrates and fats

90 % of plasma protein ( except for gammaglobulin, hemoglobin )nutrition, oncotic pressure, transportation

glycogenesis, glycogenolysis, glycolysis, gluconeogenesis

triglycerides, VLDL, LDL, HDL, cholesterol

Production, metabolism and excretion of bileProduction, metabolism and excretion of bile

น/&าด' : bilirubin, bile acids / salts, electrolytes, cholesterol, fatty acids, น/&า, lecithin

primary bile acids : cholic, chenodeoxycholic acids

secondary bile acids : deoxycholic, lithocholic acids

enterohepatic circulation bilirubin : hemoglobin, myoglobin, cytochromes,

catalase unconjugated bilirubinunconjugated bilirubin ( + albumin )

Production, metabolism and excretion of bileProduction, metabolism and excretion of bile

Protein Y & Z , Ligandin UDPG - TUDPG - T ( Uridyldiphosphate glucuronyl

transferase ) conjugated bilirubinconjugated bilirubin ( + glucuronic acids )

urobilinogen, stercobilin

biliprotein biliprotein ( delta bilirubin )

jaundice / ictericjaundice / icteric ( TB > > 2.52.5 mg /dl )

Jaundice classified by originJaundice classified by origin

1. Prehepatic ( TB < 5 mg/dl5 mg/dl) : Hereditary hemolytic processes Acquired hemolytic processes Ineffective erythropoiesis Impaired delivery of bilirubin to the

liver Sport injuries

Jaundice classified by originJaundice classified by origin

2. Hepatic : Pre - microsomal Microsomal Post - microsomal Intrahepatic obstruction

3. Posthepatic : CBD stones Cancers of the bile ducts, pancreas Stricture, stenosis, atresia Cholagitis, Choledochal cysts

Physiological classification of JaundicePhysiological classification of Jaundice

1. Unconjugated Hyperbilirubinemia Production Delivery to hepatocyte Uptake across hepatocytic membrane Storage in cytosol Conjugation

Physiological classification of JaundicePhysiological classification of Jaundice

2. Conjugated Hyperbilirubinemia Secretion into canaliculi Drainage Intrahepatic obstruction Septicemia, total parenteral nutrition Drugs

Inherited Disorder of Bilirubin MetabolismInherited Disorder of Bilirubin Metabolism

Gilbert’s syndrome :Gilbert’s syndrome : mild fluccuate unconjugated hyperbilirubinemia conjugation +/- uptake normal lifespan

Crigler - Najjar syndrome :Crigler - Najjar syndrome : severe unconjugated hyperbilirubinemia Type I : absence of UDPG - T Type II : partial defect of UDPG - T

Inherited Disorder of Bilirubin MetabolismInherited Disorder of Bilirubin Metabolism

Dubin - Johnson syndrome :Dubin - Johnson syndrome : mild fluccuate conjugated hyperbilirubinemia hepatic excretion normal lifespan hepatic pigmentation, bilirubinuria

Rotor syndrome :Rotor syndrome : unknown defect similar to Dubin - Johnson syndrome no hepatic pigmentation

Detoxification and Drug MetabolismDetoxification and Drug Metabolism

Phase IPhase I : : oxidation, hydroxylation

Phase IIPhase II : : conjugation with glucuronic acid, glycine, taurine and sulfate

Cytochrome P450 and allied hepatic enzyme Cytochrome P450 and allied hepatic enzyme systemsystem

Epoxide hydrolase UDP - glucuronosyl transferase Sulphotransferase Glutathione S - transferase

Enzymes SynthesisEnzymes Synthesis

Cytoplasmic enzyme : AST(SGOT), ALT(SGPT), LD Mitochondrial enzyme : AST Canalicular enzyme : ALP, GGT

Storage of Vitamins and MineralsStorage of Vitamins and Minerals

Fat soluble vitamins ( A, D, E, K )

Vitamin B12

Iron

Copper

Biotransformation or inactivation of hormonesBiotransformation or inactivation of hormones

Somatomedin

Glucagon

PhagocytosisPhagocytosis

Kupffer cells Pit cells

LIVER FUNCTION TESTSLIVER FUNCTION TESTS

1. Routine ( Conventional ) LFTs

bilirubin, urobilinogen, ALP, AST, ALT, GGT

2. True tests of liver function ( QLFTs : Quantitative LFTs )

Dynamic test ; measure metabolite / excretion rate,

liver blood flow or functional hepatic mass

QLFTsQLFTs

Metabolic Capacity : Indocyanine Green ( ICG ) test 14C- Galactose breath test

Microsomal enzyme function : Aminopurine breath test

Caffeine breath test

Functional hepatic perfusion : Galactose tolerance test ICG ( low dose ) test

Microsomal enzyme function and hepatic perfusion : Lidocaine clearance test

LIVER FUNCTION TESTSLIVER FUNCTION TESTS

3. Provide information about severity and prognosis

TP, Alb, Clotting factors, Ammonia

4. Special laboratory tests Alpha-1-antitrypsin, Alpha-fetoprotein,

Autoantibodies Ceruloplasmin, Copper, Hepatitis markers Immunoglobulin, Iron and ferritin, Glutamine, LD

Serum BilirubinSerum Bilirubin

Newborn

(Direct spectrophotometric method)

> 1month

(Colorimetric Wahlefeld method)

Urobilinogen in urine & fecesUrobilinogen in urine & feces

Urinary urobilinogen

Hemolytic disease

Viral hepatitis

Fecal urobilinogen

Biliary obstruction

Hepatocellular disease

LIVER ENZYMESLIVER ENZYMES

Principles of Diagnostic Enzymology

Half - life of liver enzymes in serum

ALP ………..3 - 7 วิ�น ALT……….. 50 ช�*วิโมง

AST…………12 - 14 ช�*วิโมง GGT………..7 - 10 วิ�น

Factors affecting enzyme levels in serumFactors affecting enzyme levels in serum

1. Leakage of enzymes from cells Hypoxia, Chemicals and drugs, Physical

agents, Microbiological agents, Immune mechanisms, Genetic defects, Nutritional disorders

2. Altered enzyme production

3. Clearance of enzymes

average half - life in serum 6-48 6-48 ช�*วิโมงช�*วิโมง

Characteristics of Elevated ConcentrationCharacteristics of Elevated Concentration

Mild : AST, ALT, GGT << 2 - 3 2 - 3 xx URL ALP < 1.5 - 2 x< 1.5 - 2 x URLModerate : AST, ALT up to 20 x20 x URL GGT up to 10 x10 x URL ALP up to 5 x5 x URLMarked : AST, ALT > 20 x> 20 x URL GGT > 10 x> 10 x URL ALP > 5 x> 5 x URL

AST &ALTAST &ALT

Mild : Fatty liver

NASH ( Nonalcoholic steatohepatitis )

Chronic viral hepatitis

Marked : Acute viral hepatitis

Drug or Toxin induced hepatic necrosis

Ischemic hepatitis

AST &ALTAST &ALT > 2 : Alcoholic liver disease > 1 : Cirrhosis < 1 : NASH Viral hepatitis

Aspartate Transaminase Aspartate Transaminase (AST(AST,SGOT,SGOT))

UV assay : Pyridoxal phosphate

Tissue Sources : cardiac tissue, liver, skeletal muscle, kidney, pancreas, RBC

Sources of Error : hemolysis

Diagnostic Significances : Cardiac disease, Hepatobiliary disease, Major crush injuries, Skeletal muscle disease, Pancreatitis, Delerium tremens.

PregnancyPregnancy

Alanine Transaminase ( AAlanine Transaminase ( ALLTT,SGPT,SGPT ) )

UV assay : Pyridoxal phosphate

Tissue Sources : liver

Sources of Error : hemolysis

Diagnostic Significances :

Hepatobiliary disease, Heart failure with hepatic necrosis

Alkaline Phosphatase ( ALP )Alkaline Phosphatase ( ALP )

ALP >> 33 x URL x URL Hepatobiliary disease ( cholestasis )

Marked increase

Extrahepatic biliary obstruction

PBC ( Primary Biliary Cirrhosis )

PSC ( Primary Sclerosing Cholangitis )

Drug - induced cholestasis

Mild - moderate increase Amyloidosis

Granulomatous disease

Neoplasms, Hodgkin’s disease

Renal cell carcinoma

Alkaline Phosphatase ( ALP )Alkaline Phosphatase ( ALP )Colorimetric assay : ++MgTissue Sources : intestinal epithelium, liver (sinusoidal and bile ca

nalicular membrane), bone (osteoblast), kidney tubules, placenta, spleen

Sources of Error : phosphate, borate, oxalate, cyanide, L-

phenylalanine, urea, hemolysis

Diagnostic Significances : Hepatobiliary disease, Bone disease, Healing fra

cture, Normal growth,Pregnancy Hereditary hypophosphatasiaHereditary hypophosphatasia

Alkaline Phosphatase ( ALP )Alkaline Phosphatase ( ALP )

Diagnostic Significances

Isoenzymes ; liver(heat stable), bone(heat labile),

intestinal and placental

Placenta-like ( Regan & Nagao ) ; germ cell tumors, seminoma, serous carcinoma of ovary, endometrial carcinoma and leukemia

- Glutamyl Tran- Glutamyl Transfersferase ( GGT )ase ( GGT )

Enzymatic Colorimetric assay

Tissue sources : cell membrane and mitochondria Sources of Error : smoking, pregnancy, alcohol, phenytoin, ba

rbiturate, carbamazepine, valproic acid,oral contraceptive

- Glutamyl Tran- Glutamyl Transfersferase ( GGT )ase ( GGT )

Diagnostic Significances :

Hepatobiliary disease, Hepatic microsomal enzyme induction ( drugs ; warfarin, phenytoin,

phenobarbital ), Alcoholism and heavy drinking, Pancreatitis,

Diabetic mellitus, Congestive cardiac failure

Lactate Dehydrogenase ( LD, LDH )Lactate Dehydrogenase ( LD, LDH )UV assay

Tissue Sources : myocardium, kidney, liver, skeletal muscle and RBC

Sources of Error : hemolysis

Diagnostic Significances : AMI, Hepatobiliary disease,Renal disease,Cancers, Anemia, Progressive muscular

dystrophy, Isoenzymes( LD1,2,3,4,5 )

Liver EnzymesLiver Enzymes

Routine AST, ALT, ALP

Liver specific OCT (Ornithine Carbamoyl Transferase) ID (Iditol Dehydrogenase), Guanase hepatic isoenzyme of ALP

Liver EnzymesLiver Enzymes

Interpretation

AST&ALT ………..hepatocellular damage

ALP…………………cholestasis

Plasma ProteinsPlasma ProteinsColorimetric assay

Hyperproteinemia : Dehydration, Liver diseases, Chronic inflammatory diseases, Increased plasma immunoglobulins, Faulty technique in blood sample

Hypoproteinemia : Overhydration, Pregnancy, Malnutrition, Liver diseases, Protein loss, Hypogammaglobulinemia, Hyperthyroidism

AlbuminAlbuminColorimetric assay : Dye-binding method

Sources of Error : hemolysis

Hypoalbuminemia : Hereditary defects, Malnutrition, Malabsorptive disease, Severe burn, Shock, Chronic liver disease, Major surgery, Accidental trauma, Infection, Renal disease, Exfoliative dermatitis

Protein-losing gastroenteropathy,

Clotting FactorsClotting Factors

Quick’s One Stage Prothrombin Time or Plasma Prothrombin Time

Extrinsic pathway

Factors : I, II, V, VII, X

INR ( International Normalized Ratio )

AmmoniaAmmonia Enzymatic kinetic assay

EDTA plasma, hemolysis, protein in food, EDTA plasma, hemolysis, protein in food, drugs, exercisedrugs, exercise

Diagnostic Significances ;Diagnostic Significances ; Reye’Reye’

s syndrome, Liver disease, Cirrhosis, Hepatic s syndrome, Liver disease, Cirrhosis, Hepatic coma, Hyperornithinemiacoma, Hyperornithinemia

Unexplained lethargy and vomiting, Unexplained lethargy and vomiting, Encephalitis & Neonate with unexplained neuEncephalitis & Neonate with unexplained neurologic deteriorationrologic deterioration

Ceruloplasmin(CERU; Cp )Ceruloplasmin(CERU; Cp )

Ferrioxidase activity, acute phase proteinFerrioxidase activity, acute phase protein Immunoturbidimetric methodImmunoturbidimetric method Serum, heparinized plasma, hemolysis, lipemia & rhSerum, heparinized plasma, hemolysis, lipemia & rh

eumatic factorseumatic factors

Diagnostic Significances ;Diagnostic Significances ; Wilson’s disease, MoWilson’s disease, Monkes disease, Nutritional copper deficiency, Renal nkes disease, Nutritional copper deficiency, Renal copper loss, Massive burn, Inflammation disease, copper loss, Massive burn, Inflammation disease, RE neoplasia, Biliary obstruction, Estrogen therapRE neoplasia, Biliary obstruction, Estrogen therapy, Pregnancyy, Pregnancy

Most Common Disease of LiverMost Common Disease of Liver

1. Hepatitis : Acute ( viruses, toxins and drugs )

recovery from viral hepatitis ...transaminases are norm

al within 10-1210-12 weeks

( > 6 months ………chronic )

Chronic ( autoimmune, viruses, alcohol and drugs ) : normal ALP, increased AST&ALT abnormal Albumin & PTAlbumin & PT

Most Common Disease of LiverMost Common Disease of Liver

2. Cirrhosis : Chronic excessive alcohol intake

Autoimmune chronic active hepatitis Chronic hepatitis B, C, D,

Inherited metabolic disease : Wilson’s disease, DM, Glycogen storage disease, Galactosemia

Disease of Prolonged Cholestasis : PBC, PSC, Cystic fibrosis, Biliary atresia

*decompensated cirrhosis…increased blood ammonia

Most Common Disease of LiverMost Common Disease of Liver

3. Tumours

MetastaticMetastatic : primary sites ; lung, bronchus, breast, gastrointestinal tract, prostate gland

*normal TB, AST, mild increases of GGT and ALP with marked increase of LDmarked increase of LD

Hepatoma : Cirrhosis, Hepatitis B, C, Aflatoxins*increases of alpha-fetoprotein and ALP

Differential of Hepatocellular Injury and CholestasisDifferential of Hepatocellular Injury and Cholestasis

Test Hepatocellular Injury Cholestasis

ALT > 10 x URL < 10 x URL

ALP < 3 x URL > 3 x URL

GGT < 5 x URL > 5 x URL

Bilirubin DB 50-80% DB 50-80%

PT No Respond to Vit K

Imaging studies Normal ducts Abnormal ducts

Pattern of CholestasisPattern of Cholestasis

Bilirubinostasis………… Hepatocyte

Cholestatic hepatitis……Canalicular

Ductular injury……………Intrahepatic bile ducts

Complete obstruction… Extrahepatic bile ducts

Some Drugs causing liver diseasesSome Drugs causing liver diseases

Hepatotoxicity Cholestasis Cholestatic hepatitis

Paracetamol (overdose) Salicylate( high dose) Tetracycline ( high dose) Rifampicin

Methyltestosterone Chlorpromazine Erythromycin Chlorpropamide

Comments for Interpretation of LFTsComments for Interpretation of LFTs

1. Definite diagnosis : special tests or liver biopsy

2. ALP, GGT and 5’- NT

3. Moderated or marked increase of ALP

4. AST, ALT > 10 x URL… hepatocellular hepatocellular damage

5. ALP > 3 x URL….cholestasischolestasis

Comments for Interpretation of LFTsComments for Interpretation of LFTs

6. Prolongation of PT

a. vitamin K…Advanced liver destruction

b. vitamin K…Vitamin K deficiency or Long-standing extrahepatic obstruction

7. Bile acids analysis….Inactive cirrhosis

8. Liver scan……Metastatic carcinoma

9. U/S & PTC….Extra / intrahepatic obstruction

10. Repeat LFTs …..2 -32 -3 days days

Thank you for your attentionThank you for your attention