Liver Function Tests (LFTs)

Slides:



Advertisements
Similar presentations
Serina Farzin-Nasab, MD Emory University Family Medicine Residency Program.
Advertisements

ALT/sGPT activity xiaoli.
Faculty of nursing CHEM 203 Biochemistry UNIT VIII Diagnostic Enzymes Dr.Ola Fouad Talkhan.
Liver Function Tests (LFTs)
Liver Function Tests (LFTs)
1 CLINICAL CHEMISTRY-2 (MLT 302) LIVER FUNCTION AND THE BILIARY TRACT LECTURE FOUR Dr. Essam H. Aljiffri.
1 Serum Enzymes in Disease Dr. Essam H. Aljiffri.
CLINICAL CHEMISTRY-2 (MLT 302) LIVER FUNCTION AND THE BILIARY TRACT LECTURE FIVE Dr. Essam H. Aljiffri.
AST, ALT & ALP Lab. 5.
Enzymes in Body Fluids Lecture outline
1 CLINICAL CHEMISTRY-2 (MLT 302) LIVER FUNCTION AND THE BILIARY TRACT LECTURE ONE Dr. Essam H. Aljiffri.
Dr Yasir M Khayyat,MBcHB,FRCPC,FACP 1 Khayyat Y. LFT WhyHowWhenWHO 600 ريال 2 Khayyat Y.
Sinusoids of liver are delicate structure and their walls are composed of endothelium. Sinusoids blockage can cause dilatation of these structures, liver.
The Ageing Liver Dr ‘Yinka Ogundipe SpR in Geriatric Medicine
The Liver SONO 131 Lecture #5. Anatomy Sonographic Presentation.
By Dr. Abdelaty Shawky Assistant Professor of Pathology
LIVER. 2 OVERVIEW Tests for detecting: 1. Hepatocellular injury 2. Hepatic dysfunction 3. Cholestasis.
Hepatic Function Analysis Clinical Pathology January 13, 2009.
CMP LABS By Tiffany Potter. COMPLETE METABOLIC PANEL CMP includes BMP NA ( mEq/L CL ( mmol/L) K ( mEq/L) GLU ( mg/dL) BUN (7-20.
Enzymes in Clinical Diagnosis
DESCRIPTION  Alkaline phosphatase (ALP) (EC ) catalyzes the hydrolysis of phosphate esters in an alkaline environment, resulting in the formation.
Alcohol and Abnormal Blood Tests Dr Steve Brinksman Dr Martyn Hull.
MLAB 2401: Clinical Chemistry Keri Brophy-Martinez Alterations in Liver Function.
This lecture was conducted during the Nephrology Unit Grand Ground by Medical Student rotated under Nephrology Division under the supervision and administration.
Alanine Transaminase.
Liver function tests Lecture 3.
By: H.Baniamerian Kermanshah university of medical science.
Significance of Liver Function Tests
ASSESSMENT OF LIVER FUNCTION
 Hepatic Pathology and Respiratory System Topics in Human Pathophysiology Fall 2011 Gilead Drug Safety and Public Health.
Adult Medical- Surgical Nursing Gastro-intestinal Module: Liver Cirrhosis.
Liver Function Tests. Tests Based on Detoxification and Excretory Functions.
Biochemical markers in disease diagnosis
Kidney Function Tests. Kidney Function Tests Contents: Kidney functions Functional units Renal diseases Routine kidney function tests Serum creatinine.
The Liver and digestion Dr. Than Kyaw 7 May 2012.
Blood Studies Liver function test (LFT) Group of biochemical tests Group of biochemical tests Uses of liver function test (LFTs) Differential diagnosis.
Enzyme Clinical Application
Cellular Biochemistry and Metabolism (CLS 333 ) Dr. Samah Kotb Nasr Eldeen Serum biochemical parameters (ALT) (AST) assay.
Biochemical markers for diagnosis of diseases and follow up Dr. Rana Hasanato Associate professor and consultant Head of clinical chemistry department.
Differential Diagnosis of Alkaline Phosphatase B 陳建佑.
Enzymes AST, ALT & ALP Lab. 6.
Biochemical markers for diagnosis and follow up of disease
Liver function Tests What are liver tests? Liver tests (LTs) are blood tests used to assess the general state of the liver or biliary system. Few of these.
Lab # 2 Liver Function Tests (LFTs) ALT&AST T.A. Bahiya M. Osrah.
Khadija Balubaid KAU-Faculty of Science- Biochemistry department Clinical biochemistry lab (BIOC 416) 2013 Liver Function profile (LFT) Enzymes.
Determination of plasma enzymes
Course of Advanced Diagnostics Integrated laboratory evaluation of liver Prof. Giuseppe Castaldo, a.y
prepared by Dr. Akaber Tarek Biochemistry Department Clinical Chemistry prepared by Dr. Akaber Tarek Biochemistry Department Clinical Chemistry prepared.
LIVER Liver functions Bile pigment metabolism
INTERPRETATION OF LABORATORY & DIAGNOSTIC TESTS GI SYSTEM Nora A.Kalagi, MSc. 326 PHCL April 2016.
Clinical usage of enzymes
Lab (2): Liver Function profile (LFT)
Laboratory tests in digestive systema Klinika Gastroenterologii Dr n. med. Małgorzata Pujanek.
Liver and biliary tract disorders. Synthesis of plasma proteins Albumin, prealbumin, transferin, coagulations factors…. Detoxication reactions of endogen.
LIVER FUNCTION TESTS
Liver Function Tests (LFTs)
Liver Function Tests (LFTs)
ALKALINE PHOSPHATASE This is a widely distributed enzyme which releases inorganic phosphate from many organic phosphomonoesters and also pyrophosphates.
Lab (2): Liver Function profile (LFT)
Enzymes in the Diagnosis of Pathology
INVESTIGATION OF HEPATOBILIARY DISEASE
Estimation of AST and ALT activity
Interpretation Of LAB Data
biochemical markers for diagnosis and follow up of diseases
Work hard in silence, let your success be your noise
Liver “Function” Test 2013 Mini-Lecture
Determination of the enzyme ALT (SGPT) & AST activity in serum by enzymatic method using Biophotometer.
Part 1 Liver enzyme(ALT-AST-ALP-GGT)
Gastroenterology & Nutrition Block Biochemistry Department
Determination of plasma enzymes
Presentation transcript:

Liver Function Tests (LFTs)

Major Metabolic Functions of the Liver Synthetic functions Proteins: plasma proteins albumin, globulins, coagulation factors…etc ) Lipids: cholesterol, triglycerides, fatty acids, phospholipids & lipoproteins (VLDL) Carbohydrates: glycogen synthesis & gluconeogenesis Detoxification & excretion functions - Detoxication of ammonia to urea (urea cycle) - Billirubin conjugation & excretion into bile - Excretion of cholesterol into bile - Drug detoxication & excretion into bile Storage Function - Storage of fat soluble vitamins (vitamins A, D, E & K) Storage of vitamin B12 Production of bile salts - Help digestion of lipids Patients with severe hepatic dysfunction are expected to have low plasma urea, low plasma cholesterol ,low glucose, low serum albumin and high ammonia level

Liver function tests (LFTs) Overview LFTs are blood tests used to help to diagnose & monitor disease or damage of the liver The tests measure the levels of certain enzymes & proteins in blood Some of these tests measure how well the liver is performing its normal functions of producing protein & clearing billirubin. Other liver function tests measure enzymes that liver cells release in response to damage or disease. However, 1- Conditions other than liver disease or damage can lead to abnormal liver function test results 2- Test results can be normal in people who have liver disease or damage

Liver function tests can be used to: 1- Check certain enzymes & proteins levels in blood that if are higher or lower than normal can indicate liver problems (diagnosis) 2- Screen for liver infections, such as hepatitis 3- Monitor the progression of a liver disease, such as viral or alcoholic hepatitis & determine how well a treatment is working (prognosis) 3- Measure the severity of a liver disease especially liver cirrhosis 4- Monitor possible side effects of medications on liver 3-

Routine Liver Function Tests (LFTs) 1- Serum Albumin 2- Blood Liver Enzymes: Alanine amino transferase (ALT) Aspartate amino transferase (AST) Gamma glutamyl transferase (GGT) Alkaline phosphatase (ALP) 3- Blood Billirubin (total, direct & indirect) 4- Blood Coagulation Factors (prothrombin & others) Prothrombin Time (PT) Others: Markers of liver fibrosis

Serum Albumin Albumin is present in higher concentrations than other plasma proteins ( ~ 40 g/L in normal adults). Albumin is synthesized in the liver & has a half-life of 20 days. Very small amounts of albumin cross the glomerular capillary wall. Accordingly, no more than traces of albumin may normally appear in urine that can not be detected by ordinary laboratory means. Albuminuria : In this case, albumin can be detected in urine by ordinary laboratory means due to physiological or pathological conditions.

Serum Albumin cont. Causes of hypoalbuminemia Artfuctual : Diluted sample Physiological : Pregnancy - Recumbence Decreased amino acids : Reduced essential amino acids in diet & reduced synthesis of nonessential amino acids Malnutrition Malabsorption. Increased catabolism : Surgery Trauma Infections Defective synthesis in liver: Chronic liver diseases Increased loss : From the kidney: Nephrotic syndrome From GIT: Protein loosing entropathies

Blood Aminotransferases (ALT & AST) Aminotransferases (ALT & AST) are normally intracellular enzymes Plasma contains low levels of aminotransferases representing release of cellular contents during normal cell turnover Elevated blood levels of aminotransferases indicate damage to cells rich in these enzymes (as disease to tissue or physical trauma ) Blood AST & ALT are of particular diagnostic value

Causes of elevated levels of blood ALT & AST 1- Viral , toxic or alcholic hepatitis ALT & AST are elevated even before appearance of clinical signs (jaundice) & symptoms.   Marked increase in ALT & AST (Up to 20 - 50 - may reach up to 100 folds).   Peak values between 7 – 12 days of onset of the disease In viral hepatitis, ALT is much elevated than AST 2- Cirrhosis (chronic liver diseases) ALT & AST are increased to levels depending on the status of the process (Moderate increase (up to 4 – 5 folds) In chronic cases, AST is much elevated than ALT. 3- Obstructive jaundice: ALT & AST are increased up to 3 folds (moderate increase) 4- After alcoholic or drug intake (transient slight to moderate increase).

Alanine amino transferase (ALT)   ALT is more liver specific than AST. ALT rarely increases in lesions other than the liver parenchymal ALT elevations persist longer than do AST. Aspartate transaminase (AST) Blood levels of AST are increased with many diseases of various organs: 1- Liver diseases 2- Myocardial infarction (MI) However, ALT may be also increased if liver congestion occurs secondary to congestive heart failure 3 - Progressive skeletal muscular dystrophy 4- Crush injury 5- Hemolytic diseases 6- Artifact: in hemolysed samples or if serum separation is delayed

Gamma glutamyl transferase (GGT) GGT present in blood originates primarily from hepatobillary system Causes of increased blood GGT: 1- Induction of GGT synthesis by these cells occurs without cell damage by alcohol or drugs as anticonvulsants , phenobarbitone & phenytoin 2- Biliary obstruction : GGT is markedly increased with obstructive jaundice (5 – 30 folds) Increase earlier (more sensitive) than ALP Persists longer than ALP 3- Viral, toxic & alcoholic hepatitis : Increase is only 2 – 5 folds (less sensitive than ALT & AST) 4- Primary and secondary liver tumors: GGT is elevated earlier than other enzymes in liver neoplasm. Secondaries of other organ tumors in the liver can be early detected by elevated GGT. (arouse suspicious that the diseases is metastatic to liver)

Alkaline Phosphatase (ALP)   Alkaline phosphatases (ALP) are group of enzymes that hydrolyze organic phosphates at high pH (9 – 10.5) Main Sources of ALP: 1- Cells of hepatobiliary tract (hepatocytes adjacent to the biliary canalculi) Activity in the liver is localized on those parts of the cell membrane of the parenchymal cell adjoining the biliary canalculi 2- Osteoblasts of bone : he metabolic function of ALP is probably important for bone calcification. Other Sources: Intestine and placenta & renal tubules

Alkaline Phosphatase (ALP) cont. Clinical significance of increased serum ALP activities: 1-Physiological increase of ALP: During periods of active bone growth in infancy and at puberty Preterm infants total ALP is increased to 5 times the upper reference limit of adults due to bone isoenzymes. In children under 3 years, total ALP activity is increased up to 2.5 times the upper limit Increased twice, during the second and third trimesters of pregnancy (placental ALP).

Alkaline Phosphatase (ALP) cont. 2- Pathological increase of ALP: A- Bone causes (due to increased osteoblastic activity): Tumors (osteogenic) Paget`s Disease of bone Marked increase , may be 10 – 25 folds) due to osteoblastic cells action trying to rebuild bone that is resorped by activity of osteoclasts Primary osteogenic tumors Secondary malignant deposits in bone if causing osteoblastosis e.g. cancer prostate causing deposits in bones (osteoblastic tumor) Rickets & osteomalacia (vitamin D deficiency) Primary & secondary hyperparathyroidism (increased PTH) Healing of bone fractures

Alkaline Phosphatase (ALP) cont. B-Hepatobiliray tract liver diseases with involvement of biliary tract 1- Obstructive jaundice (intrahepatic or extrahepatic) Extrahepatic cholestiasis : (Marked increase, up to 10 – 12 folds) Due to obstruction of to the flow of bile through the biliary tract by: Stones, inflammation of biliary tract or pressure from outside by cancer head of pancreas. Intrahepatic cholestiasis: (Moderate increase , ~ 3 -5 folds) Bile secretion from the hepatocytes into the canalculi is impaired by: Drugs (chlorpromazine), alcohol, inflammation of the biliary tract (cholangitis).   2- Viral, toxic & alcoholic hepatitis Mild to moderate increase, less than 3 folds (ALP may be may be normal)

If ALP is elevated due to a bone disease In this case, GGT is (or may be) normal i.e. GGT is used to ascertain whether increased ALP is due to bone or hepatobiliary disease

Coagulation factors The liver makes many of the proteins (prothrombin & other clotting factors) needed to make blood clot In certain liver disorders the liver cannot make enough of these proteins and so blood does not clot so well. Therefore, blood clotting tests may be used as a marker of the severity of certain liver disorders In liver disease, the synthesis of prothrombin & other clotting factors is diminished,  prolonged prothrombin Time (PT) This may be one of the earliest abnormalities seen in hepatocellular damage, since prothrombin has a short half-life (~ 6 hours)

Makers of Liver Fibrosis Procollagen type III terminal peptide Hyaluronic acid (hyaluronin)