Liver Function Tests_Level II Students_17 June 2008 (2)

7/29/2019 Liver Function Tests_Level II Students_17 June 2008 (2)

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LIVER FUNCTION TESTS

Level II

18 June 2008


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Liver disease

Many diseases of the liver are accompanied byjaundice caused by increased levels ofbilirubin in the system. The bilirubin results from the breakup of the hemoglobin of dead

red blood cells; normally, the liver removes bilirubin from the blood and excretes it

through bile.

Hepatitis, inflammation of the liver, caused mainly by various viruses but also bysome poisons, autoimmunity or hereditary conditions.

Cirrhosis is the formation of fibrous tissue in the liver, replacing dead liver cells.

The death of the liver cells can for example be caused by viral hepatitis,

alcoholism or contact with other liver-toxic chemicals.

Haemochromatosis, a hereditary disease causing the accumulation ofiron in thebody, eventually leading to liver damage.

Cancerof the liver (primary hepatocellular carcinoma orcholangiocarcinoma andmetastatic cancers, usually from other parts of the gastrointestinal tract).

Wilson's disease, ahereditary disease which causes the body to retain copper.

Primary sclerosing cholangitis, an inflammatory disease of thebile duct, likelyautoimmune in nature.

Primary biliary cirrhosis, autoimmune disease of small bile ducts.

Budd-Chiari syndrome, obstruction of the hepatic vein.

Gilbert's syndrome, a genetic disorder ofbilirubin metabolism, found in about 5%

of the population.

Glycogen storage disease type II,The build-up of glycogen causes progressivemuscle weakness (myopathy) throughout the body and affects various bodytissues, particularly in the heart, skeletal muscles, liver and nervous system.

There are also many pediatric liver disease, includingbiliary atresia,alpha-1 antitrypsin

deficiency, alagille syndrome, andprogressive familial intrahepatic cholestasis, to name

but a few.

A number ofliver function tests are available to test the proper function of the liver.

These test for the presence of enzymes in blood that are normally most abundant in liver

tissue, metabolites or products.

Symptoms of a diseased liver

The external signs include a coated tongue, bad breath, skin rashes, itchy skin, excessive

sweating, offensive body odour, dark circles under the eyes, red swollen and itchy eyes,

acne rosacea, brownish spots and blemishes on the skin, flushed facial appearance or

excessive facial blood vessels.[1]
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Other symptoms include jaundice, dark urine, pale stool, bone loss, easy bleeding,

itching, small, spider-like blood vessels visible in the skin, enlarged spleen, fluid in the

abdominal cavity, chills, pain from the biliary tract or pancrea, and an enlargedgallbladder.

The symptoms related to liver dysfunction include both physical signs and a variety ofsymptoms related to digestive problems, blood sugar problems, immune disorders,

abnormal absorption of fats, and metabolism problems.

The malabsorption of fats may lead to symptoms that include indigestion, reflux,

hemorhoids, gall stones, intolerance to fatty foods, intolerance to alcohol, nausea and

vomiting attacks, abdominal bloating, and constipation.

Nervous system disorders include depression, mood changes, especially anger andirritability, poor concentration, overheating of the body, especially the face and torso, and

recurrent headaches (including migraine) associated with nausea.

The blood sugar problems include a craving for sugar, hypoglycaemia and unstable blood

sugar levels, and the onset of diabetes (Type 2).

Abnormalities in the level of fats in the blood stream include elevated LDL cholesterol,

reduced HDL cholesterol, elevated triglycerides, clogged arteries leading to high blood

pressure heart attacks and strokes, build up of fat in other body organs (fatty degeneration

of organs), lumps of fat in the skin (lipomas and other fatty tumors), excessive weightgain (which may lead to obesity), inability to lose weight even while dieting, sluggish

metabolism, protuberant abdomen (pot belly), cellulite, fatty liver, and a roll of fat around

the upper abdomen (liver roll).

Liver function tests (LFTs or LFs), which include liver enzymes, are groups ofclinicalbiochemistry laboratory blood assays designed to give information about the state of a

patient'sliver. Most liver diseases cause only mild symptoms initially, but it is vital that

these diseases be detected early. Hepatic (liver) involvement in some diseases can be ofcrucial importance. This testing is performed by a medical technologist on a patient's

serum orplasma sample obtained byphlebotomy. Some tests are associated with

functionality (eg. albumin); some with cellular integrity (eg. transaminase) and some withconditions linked to the biliary tract (gamma-glutamyl transferase and alkaline

phosphatase).

LIVER ENZYMES

- Albumin (Alb) Albumin is a protein made specifically by the liver, and can be measured

cheaply and easily. It is the main constituent of total protein; the remaining fraction iscalled globulin (including the immunoglobulins).

Albumin levels are decreased in chronic liver disease, such as cirrhosis. It is also

decreased in nephrotic syndrome, where it is lost through the urine. Poor nutrition or
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states of protein catabolism may also lead to hypoalbuminaemia. The half-life of albumin

is approximately 20 days. Albumin is not considered to be an especially useful marker of

liver synthetic function; coagulation factors (see below) are much more sensitive. 3.9 to5.0 g/dL [1]

-Alanine transaminase (ALT) || Alanine transaminase (ALT), also called Serum GlutamicPyruvate Transaminase(SGPT) or Alanine aminotransferase (ALAT) is an enzyme

present in hepatocytes (liver cells). When a cell is damaged, it leaks this enzyme into theblood, where it is measured. ALT rises dramatically in acute liver damage, such asviral

hepatitis orparacetamol (acetaminophen) overdose. Elevations are often measured in

multiples of the upper limit of normal (ULN).

-Aspartate transaminase (AST) Aspartate transaminase (AST) also called Serum

Glutamic Oxaloacetic Transaminase (SGOT) or aspartate aminotransferase (ASAT) is

similar to ALT in that it is another enzyme associated with liver parenchymal cells. It is

raised in acute liver damage, but is also present in red cells, and cardiac and skeletal

muscle and is therefore not specific to the liver. The ratio of AST to ALT is sometimesuseful in differentiating between causes of liver damage. || 10 to 40 IU/L

-Alkaline phosphatase (ALP) ||Alkaline phosphatase (ALP) is an enzyme in the cells

lining thebiliary ductsof the liver. ALP levels in plasma will rise with large bile ductobstruction, intrahepatic cholestasis or infiltrative diseases of the liver. ALP is also

present inbone andplacental tissue, so it is higher in growing children (as their bones are

being remodelled) and elderly patients with Paget's disease. || 30 to 120 IU/L

-Total bilirubin (TBIL) || Bilirubin is a breakdown product ofheme (a part of

haemoglobin in red blood cells). The liver is responsible for clearing the blood of

bilirubin. It does this by the following mechanism: bilirubin is taken up into hepatocytes,conjugated(modified to make it water-soluble), and secreted into thebile, which isexcreted into the intestine.

Increased total bilirubin causes jaundice, and can signal a number of problems:

1. Prehepatic: Increased bilirubinproduction. This can be due to a number of

causes, including hemolytic anemias and internal hemorrhage.

2. Hepatic: Problems with the liver, which are reflected as deficiencies in

bilirubin metabolism (e.g. reduced hepatocyte uptake, impaired conjugation of

bilirubin, and reduced hepatocyte secretion of bilirubin). Some examples would

be cirrhosis and viral hepatitis. 3. Posthepatic: Obstruction of the bile ducts, reflected as deficiencies in bilirubin

excretion. (Obstruction can be located either within the liver oroutside the liver.)

- Direct bilirubin || The diagnosis is narrowed down further by looking at the levels ofdirect bilirubin.
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If direct (i.e. conjugated) bilirubin is normal, then the problem is an excess of

unconjugated bilirubin, and the location of the problem is upstream of bilirubin

excretion. Hemolysis, viral hepatitis, or cirrhosis can be suspected.

If direct bilirubin is elevated, then the liver is conjugating bilirubin normally, but

is not able to excrete it. Bile duct obstruction by gallstones or cancer should be

suspected.

| 0 - 4 mol/L

- Gamma glutamyl transpeptidase (GGT) || Although reasonably specific to the liver anda more sensitive marker for cholestatic damage than ALP, Gamma glutamyl

transpeptidase (GGT) may be elevated with even minor, sub-clinical levels of liver

dysfunction. It can also be helpful in identifying the cause of an isolated elevation inALP. GGT is raised in alcohol toxicity (acute and chronic). In some laboratories, GGT is

not part of the standard LFTs and must be specifically requested. || 0 to 51 IU/L

Other tests commonly requested alongside LFTs:5' nucleotidase (5'NTD)

5' nucleotidase is another test specific for cholestasis or damage to the intra or

extrahepatic biliary system, and in some laboratories, is used as a substitute for GGT for

ascertaining whether an elevated ALP is of biliary or extra-biliary origin.

Coagulation tests (e.g. INR)

The liver is responsible for the production ofcoagulation factors. The international

normalized ratio (INR) measures the speed of a particular pathway of coagulation,comparing it to normal. If the INR is increased, it means it is taking longer than usual for

blood to clot. The INR will only be increased if the liver is so damaged that synthesis ofvitamin K-dependent coagulation factors has been impaired: it is not a sensitive measure

of liver function.

It is very important to normalize the INR before operating on people with liver problems

(usually by transfusion with blood plasma containing the deficient factors) as they couldbleed excessively.

Serumglucose (BG, Glu)

The liver's ability to produce glucose (gluconeogenesis) is usually the last function to belost in the setting of fulminant liver failure.

Lactate dehydrogenase (LDH)
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Lactate dehydrogenaseis an enzyme found in many body tissues, including the liver.

Elevated levels of LDH may indicate liver damage.

Introduction

An initial step in detecting liver damage is a simple blood test to determine the presenceof certain liver enzymes in the blood. Under normal circumstances, these enzymes reside

within the cells of the liver. But when the liver is injured, these enzymes are spilled into

the blood stream.

Among the most sensitive and widely used of these liver enzymes are theaminotransferases. They include aspartate aminotransferase (AST or SGOT) and alanine

aminotransferase (ALT or SGPT). These enzymes are normally contained within liver

cells. If the liver is injured, the liver cells spill the enzymes into blood, raising theenzyme levels in the blood and signaling the liver damage.

What are the aminotransferases?

The aminotransferases catalyze chemical reactions in the cells in which an amino groupis transferred from a donor molecule to a recipient molecule. Hence, the names

"aminotransferases".

Medical terms can sometimes be confusing, as is the case with these enzymes. Another

name for aminotransferase is transaminase. The enzyme aspartate aminotransferase(AST) is also known as serum glutamic oxaloacetic transaminase (SGOT); and alanine

aminotransferase (ALT) is also known as serum glutamic pyruvic transaminase (SGPT).

To put matters briefly, AST = SGOT and ALT = SGPT.

Normally, where are the aminotransferases?

AST (SGOT) is normally found in a diversity of tissues including liver, heart, muscle,

kidney, and brain. It is released into serum when any one of these tissues is damaged. Forexample, its level in serum rises with heart attacks and with muscle disorders. It is

therefore not a highly specific indicator of liver injury.

ALT (SGPT) is, by contrast, normally found largely in the liver. This is not to say that it

is exclusively located in liver but that is where it is most concentrated. It is released intothe bloodstream as the result of liver injury. It therefore serves as a fairly specific

indicator of liver status.
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Alanine transaminase

Alanine transaminase orALT is a transaminaseenzyme. It is also called serumglutamate pyruvate transaminase (SGPT) oralanine aminotransferase (ALAT).

ALT is found in serum and in various bodily tissues, but is most commonly associated

with the liver;

Function

It catalyzes the transfer of an amino group from alanine to a-ketoglutarate, the products

of this reversible transamination reaction beingpyruvateandglutamate.

glutamate+pyruvate -ketoglutarate +alanine

Alanine transaminase

Clinical significance

It is commonly measured clinically as a part of a diagnostic liver function test, to

determine liver health. Diagnostically, it is almost always measured in units/litre (U/L).

Elevated levels

Significantly elevated levels of ALT often suggest the existence of other medical

problems such as alcoholic or viralhepatitis,congestive heart failure, liverdamage,

biliary duct problems, infectious mononucleosis, ormyopathy. For this reason, ALT iscommonly used as a way of screening for liver problems. However, elevated levels of

ALT do not automatically mean that medical problems exist. Fluctuation of ALT levels is

normal over the course of the day, and ALT levels can also increase in response to

strenuous physical exercise.
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When elevated ALT levels are found in the blood, the possible underlying causes can be

further narrowed down by measuring other enzymes. For example, elevated ALT levels

due to liver-cell damage can be distinguished frombiliary duct problems by measuringalkaline phosphatase. Also, myopathy-related ALT levels can be ruled out by measuring

creatine kinase enzymes.

For years, the American Red Cross used ALT testing as part of the battery of tests to

ensure the safety of its blood supply by deferring donors with elevated ALT levels. Theintent was to identify donors potentially infected withHepatitis C ("non-A non-B

Hepatitis") because there was no specific test for that disease at the time. With the

introduction of second generationELISA antibody tests forHepatitis C, the Red Crosschanged the ALT policy. As of July 2003, donors previously disqualified for elevated

ALT levels and no other reason may be reinstated as donors by contacting the donor

counseling department of their regional Red Cross organization.

Alanine amino transfraseL'alanine amino transfrase (ALAT ou ALT) est une enzyme faisant partie des

transaminasesdont l'activit est mesure en biologie clinique lors du bilan hpatique. Elle

se trouve en quantit importante surtout dans lefoie. Son augmentation dans leplasmasanguin signe une cytolyse hpatique.

L'alanine amino transfrase est capable de transfrer le groupementamine de l'acide

glutamique sur l'acide pyruvique avec formation d'une molcule d'acide -ctoglutarique(un acide -ctonique) et d'alanine (un autre acide -amin) selon :

Attention schma : il manque un H au C de l'alanine (dernire molcule de droite) Lavaleur de rfrence est infrieure 65 U/l.

Ancien nom

Elle fut autrefois appele glutamate pyruvate transaminase(TGP ou GPT ou SGPT).
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Aspartate transaminase

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Aspartate transaminase(AST) also calledserum glutamic oxaloacetic transaminase

(SGOT) oraspartate aminotransferase

(ASAT/AAT) is similar toalanine transaminase

(ALT) in that it is another enzyme associated withliverparenchymal cells.

Function

It facilitates the conversion ofaspartate and alpha-

ketoglutarate to oxaloacetate and glutamate.

Isozymes

Two isoenzymes are present in humans. They have high similarity.

GOT1, the cytosolic isoenzyme derives mainly fromred blood cellsandheart.

GOT2, the mitochondrial isoenzyme is predominantly present in liver.

Clinical significance

It is raised in acute liver damage. It is also present inred blood cellsandcardiac muscle,

skeletal muscle, and kidney and brain tissue, and may be elevated due to damage to those

sources as well.

AST was defined as a biochemical marker for the diagnosis of acute myocardialinfarction in 1954. However the use of AST for such a diagnosis is now redundant and

has been superseded by the cardiac troponins.[1]

AST (SGOT) is commonly measured clinically as a part of diagnostic liver function tests,to determine liverhealth.

References

1. ^ Gaze DC (2007). "The role of existing and novel cardiac biomarkers forcardioprotection". Curr. Opin. Invest. Drugs8 (9): 711-717.PMID 17729182.

Journal articles

Aspartate aminotransferase

Aspartate aminotransferase.

Aspartate aminotransferase from

Escherichia coli bound with cofactor

pyridoxal 5-phosphate (PDB1AAM)

Gene code:

Structure:
http://en.wikipedia.org/wiki/Aspartate_transaminase#column-one%23column-onehttp://en.wikipedia.org/wiki/Aspartate_transaminase#column-one%23column-onehttp://en.wikipedia.org/wiki/Aspartate_transaminase#searchInput%23searchInputhttp://en.wikipedia.org/wiki/Transaminasehttp://en.wikipedia.org/wiki/Transaminasehttp://en.wikipedia.org/wiki/Alanine_transaminasehttp://en.wikipedia.org/wiki/Alanine_transaminasehttp://en.wikipedia.org/wiki/Parenchymalhttp://en.wikipedia.org/wiki/Aspartatehttp://en.wikipedia.org/wiki/Alpha-ketoglutaratehttp://en.wikipedia.org/wiki/Alpha-ketoglutaratehttp://en.wikipedia.org/wiki/Oxaloacetatehttp://en.wikipedia.org/wiki/Glutamatehttp://www.genenames.org/data/hgnc_data.php?match=GOT1http://en.wikipedia.org/wiki/Cytosolhttp://en.wikipedia.org/wiki/Red_blood_cellhttp://en.wikipedia.org/wiki/Red_blood_cellhttp://en.wikipedia.org/wiki/Red_blood_cellhttp://en.wikipedia.org/wiki/Hearthttp://en.wikipedia.org/wiki/Hearthttp://www.genenames.org/data/hgnc_data.php?match=GOT2http://en.wikipedia.org/wiki/Mitochondrionhttp://en.wikipedia.org/wiki/Red_blood_cellhttp://en.wikipedia.org/wiki/Red_blood_cellhttp://en.wikipedia.org/wiki/Red_blood_cellhttp://en.wikipedia.org/wiki/Myocardiumhttp://en.wikipedia.org/wiki/Myocardiumhttp://en.wikipedia.org/wiki/Myocardiumhttp://en.wikipedia.org/wiki/Aspartate_transaminase#cite_note-0%23cite_note-0http://en.wikipedia.org/wiki/Aspartate_transaminase#cite_note-0%23cite_note-0http://en.wikipedia.org/wiki/Liver_function_testshttp://en.wikipedia.org/wiki/Liverhttp://en.wikipedia.org/wiki/Liverhttp://en.wikipedia.org/wiki/Aspartate_transaminase#cite_ref-0%23cite_ref-0http://www.ncbi.nlm.nih.gov/pubmed/17729182http://www.ncbi.nlm.nih.gov/pubmed/17729182http://en.wikipedia.org/wiki/Aspartate_aminotransferasehttp://en.wikipedia.org/wiki/E._colihttp://en.wikipedia.org/wiki/Pyridoxal-phosphatehttp://en.wikipedia.org/wiki/Protein_Data_Bankhttp://www.rcsb.org/pdb/explore/explore.do?structureId=1AAMhttp://en.wikipedia.org/wiki/Image:1AAM.pnghttp://en.wikipedia.org/wiki/Aspartate_transaminase#column-one%23column-onehttp://en.wikipedia.org/wiki/Aspartate_transaminase#searchInput%23searchInputhttp://en.wikipedia.org/wiki/Aspartate_aminotransferasehttp://en.wikipedia.org/wiki/E._colihttp://en.wikipedia.org/wiki/Pyridoxal-phosphatehttp://en.wikipedia.org/wiki/Protein_Data_Bankhttp://www.rcsb.org/pdb/explore/explore.do?structureId=1AAMhttp://en.wikipedia.org/wiki/Transaminasehttp://en.wikipedia.org/wiki/Alanine_transaminasehttp://en.wikipedia.org/wiki/Parenchymalhttp://en.wikipedia.org/wiki/Aspartatehttp://en.wikipedia.org/wiki/Alpha-ketoglutaratehttp://en.wikipedia.org/wiki/Alpha-ketoglutaratehttp://en.wikipedia.org/wiki/Oxaloacetatehttp://en.wikipedia.org/wiki/Glutamatehttp://www.genenames.org/data/hgnc_data.php?match=GOT1http://en.wikipedia.org/wiki/Cytosolhttp://en.wikipedia.org/wiki/Red_blood_cellhttp://en.wikipedia.org/wiki/Hearthttp://www.genenames.org/data/hgnc_data.php?match=GOT2http://en.wikipedia.org/wiki/Mitochondrionhttp://en.wikipedia.org/wiki/Red_blood_cellhttp://en.wikipedia.org/wiki/Myocardiumhttp://en.wikipedia.org/wiki/Aspartate_transaminase#cite_note-0%23cite_note-0http://en.wikipedia.org/wiki/Liver_function_testshttp://en.wikipedia.org/wiki/Liverhttp://en.wikipedia.org/wiki/Aspartate_transaminase#cite_ref-0%23cite_ref-0http://www.ncbi.nlm.nih.gov/pubmed/17729182


10/10

Kuramitsu S, Okuno S, Ogawa T, Ogawa H, Kagamiyama H (1985). "Aspartate

aminotransferase of Escherichia coli: nucleotide sequence of the aspC gene". J.

Biochem.97 (4): 1259-62. PMID 3897210.

Kondo K, Wakabayashi S, Yagi T, Kagamiyama H (1984). "The complete amino

acid sequence of aspartate aminotransferase from Escherichia coli: sequencecomparison with pig isoenzymes".Biochem. Biophys. Res. Commun.122 (1): 62-

7. doi:10.1016/0006-291X(84)90439-X.PMID 6378205.

Inoue K, Kuramitsu S, Okamoto A, Hirotsu K, Higuchi T, Kagamiyama H (1991).

"Site-directed mutagenesis of Escherichia coli aspartate aminotransferase: role of

Tyr70 in the catalytic processes".Biochemistry30 (31): 7796-801.doi:10.1021/bi00245a019. PMID 1868057.

Aspartate amino transfrase

L'Aspartate aminotransfrase (ASAT ou AST) est une enzyme faisant partie des

transaminasesdont l'activit est mesure enbiologie clinique lors de certaines maladies.

Elle se trouve en quantit importante dans les muscles, cardiaque et squelettiques, dans le

foie, le rein et le cerveau. Une atteinte de ces diffrents organes, comme par exemple lorsd'un infarctus du myocarde ou d'une hpatite, entraine la libration de cette enzyme dans

le sang et l'augmentation de son taux dans leplasma sanguin.

Les ASAT sont comprises gnralement entre 20 et 40 UI/l (units internationales), lafourchette variant selon les laboratoires.

L'autretransaminase, l'alanine amino transfrase(ALAT ou SGPT), est principalement

prsente dans le foie. Ainsi dans les maladies du foie, l'lvation desALAT est

suprieure l'lvation des ASAT, alors que dans les maladies des muscles, l'lvationdes ALAT est infrieure l'lvation des ASAT.

Ancien nom

Elle fut autrefois appele Glutamate Oxaloactique Transaminase(ou SGOT).

Alanine amino transfrase (ALAT ou SGPT), l'autre transaminase principalement

augmente dans les maladies du foie.
http://www.ncbi.nlm.nih.gov/pubmed/3897210http://en.wikipedia.org/wiki/Digital_object_identifierhttp://dx.doi.org/10.1016%2F0006-291X(84)90439-Xhttp://www.ncbi.nlm.nih.gov/pubmed/6378205http://www.ncbi.nlm.nih.gov/pubmed/6378205http://en.wikipedia.org/wiki/Digital_object_identifierhttp://dx.doi.org/10.1021%2Fbi00245a019http://www.ncbi.nlm.nih.gov/pubmed/1868057http://fr.wikipedia.org/wiki/Enzymehttp://fr.wikipedia.org/wiki/Transaminasehttp://fr.wikipedia.org/wiki/Transaminasehttp://fr.wikipedia.org/wiki/Biologie_cliniquehttp://fr.wikipedia.org/wiki/Muscleshttp://fr.wikipedia.org/wiki/Foiehttp://fr.wikipedia.org/wiki/Reinhttp://fr.wikipedia.org/wiki/Cerveauhttp://fr.wikipedia.org/wiki/Plasma_sanguinhttp://fr.wikipedia.org/wiki/Plasma_sanguinhttp://fr.wikipedia.org/wiki/Transaminasehttp://fr.wikipedia.org/wiki/Transaminasehttp://fr.wikipedia.org/wiki/Alanine_amino_transf%C3%A9rasehttp://fr.wikipedia.org/wiki/Alanine_amino_transf%C3%A9rasehttp://fr.wikipedia.org/wiki/ALAThttp://fr.wikipedia.org/wiki/ALAThttp://fr.wikipedia.org/wiki/ALAThttp://fr.wikipedia.org/wiki/Glutamate_Oxaloac%C3%A9tique_Transaminasehttp://fr.wikipedia.org/wiki/Glutamate_Oxaloac%C3%A9tique_Transaminasehttp://fr.wikipedia.org/wiki/Alanine_amino_transf%C3%A9rasehttp://fr.wikipedia.org/wiki/Transaminasehttp://fr.wikipedia.org/wiki/Foiehttp://www.ncbi.nlm.nih.gov/pubmed/3897210http://en.wikipedia.org/wiki/Digital_object_identifierhttp://dx.doi.org/10.1016%2F0006-291X(84)90439-Xhttp://www.ncbi.nlm.nih.gov/pubmed/6378205http://en.wikipedia.org/wiki/Digital_object_identifierhttp://dx.doi.org/10.1021%2Fbi00245a019http://www.ncbi.nlm.nih.gov/pubmed/1868057http://fr.wikipedia.org/wiki/Enzymehttp://fr.wikipedia.org/wiki/Transaminasehttp://fr.wikipedia.org/wiki/Biologie_cliniquehttp://fr.wikipedia.org/wiki/Muscleshttp://fr.wikipedia.org/wiki/Foiehttp://fr.wikipedia.org/wiki/Reinhttp://fr.wikipedia.org/wiki/Cerveauhttp://fr.wikipedia.org/wiki/Plasma_sanguinhttp://fr.wikipedia.org/wiki/Transaminasehttp://fr.wikipedia.org/wiki/Alanine_amino_transf%C3%A9rasehttp://fr.wikipedia.org/wiki/ALAThttp://fr.wikipedia.org/wiki/ALAThttp://fr.wikipedia.org/wiki/Glutamate_Oxaloac%C3%A9tique_Transaminasehttp://fr.wikipedia.org/wiki/Alanine_amino_transf%C3%A9rasehttp://fr.wikipedia.org/wiki/Transaminasehttp://fr.wikipedia.org/wiki/Foie

Liver Function Tests_Level II Students_17 June 2008 (2)

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