Liver Function tests
Liver function Tests (LFTs) are the most commonly requested screening blood tests.
Whether for the investigation of suspected liver disease, monitoring of disease activity , or
simply as "routine" blood analysis , these tests can provide a host of information on a
range of disease processes .
Basically the evaluation of liver enzymes gives information as to whether a patient's
primary disorder is liver or bile. Get to know the types of liver function tests are ,their
normal values and what they might indicate , but must put in mind that these tests should
only be requested by your physician as they are not inclusive and require more
investigation to confirm a liver disease .
AST/SGOT:
Aspartate Transaminase (Enzyme; marker for cell injury )
Normal Value = 5-30/L
Helpful in identifying liver injury (Cirrhosis, hepatitis, etc)
AST is present in many organs and not specific to liver , but can be an indicator
among other tests.
It's red alarm when it jump 3-5 times the normal ratio, but almost nothing to
worry about when it,s less than that .
In acute hepatitis the number may reach up to hundreds – thousands times the
normal value, but in the end –stage liver disease it may be very low .
ALT/SGOT
Alanine Transaminase (Enzyme; marker for cell injury)
Normal Value =6-37U/L
Helpful in identifying liver injury(Cirrhosis, hepatitis, etc)
It's more specific than AST but requires other tests ass well.
It's red alarm when it jump 3-5 times the normal ratio , , but almost nothing to
worry about when it,s less than that .
, but almost nothing to worry about when it,s less than that .
In acute hepatitis the number may reach up to hundreds – thousands times the
normal value, but in the liver disease's end stage it may be very low .
ALP
Alkaline Phosphatase (Enzyme; marker for cell injury and obstructive bile diseases)
Normal Value = 30-90 U/L
Helpful in Identifying Liver ,bile and bone disorder
Sometimes it gets elevated in the middle of pregnancy and remains high till
delivery .Its level may also rise in childhood .
ALP elevation should be in parallel with bilirubin- indices as well as GGT to
indicate obstructive liver /bile diseases .
GGT
Gamma Glutamyl Transferase (Enzyme ;marker for cell in injury and obstructive bile
diseases )
Normal Value : Males =6-45 U/L Females = 5-30 U/L
It's one of the specific tests for liver dysfunctions (especially cirrhosis) and it's bing
used by most of the alcoholic addiction centers as it's level are dowen after 2-3
weeks of abstinence
It's red alarm when it jump 2-3 times the normal ratio .
Helpful to detect alcoholism and to confirm the hepatic origin in elevated ALP.
Albumin
Albumin (plasma protein ;Marker for liver synthetic functions)
Normal Value= 3.5-5.5g/dl
It's a very specific test for liver synthetic functions as its only synthesized in the
liver where low levels of albumin indicates chronic infection & liver cirrhosis and
ascites .
PT.PTT .INR
(PT) Prothrombin Time ,( PTT) Partial Thromboplastin Time , (INR)
the time it takes for your blood to clot. This way of determining Prothrombin time creates
results that will vary depending on the laboratory and the method used to test the blood,
but a sample range is approximately 10 to 14 seconds .
Normal value PTT=60-70 seconds
Normal Value INR: ≤1.3--≥5.5 & ≥20 seconds
Those tests are requested for liver (or any other organ) if there is any bleeding
without a Known cause .
Also, indicate for liver synthetic Functions(e.g. cirrhosis, hepatitis, and neoplastic
invasive processes ).
DBil &TBil
Direct &Total Bilirubin; Markers of Liver excretory Functions:
Normal Value DBIL =0.1--0.3 mg/dL
Normal Value TBIL=0.3—1.0 mg/dL
Newborn TBIL =1.0—12.0mg/dl
Possible Critical Values:
Total Bilirubin:
Adult : ≥12mg/dL (Jumps 2-3 times the normal ratio .
Newborn: ≥15mg/dL
Bilirubin indicates bile and liver disorders
Prepared by : Dr Hadia El-Aasser
Consultant of Public Health and Pediatrics
From : MOSBY's -Diagnostic and Laboratory Test Reference Tenth Sdition
PAGANA*PAGANA
ELSEVIER
