Liver Lab Tests Flashcards
(64 cards)
What is a liver biochemical test called?
liver function test/hepatic panel
Why is the LFT not accurate at showing how well the liver is functioning?
- it can be ABNORMAL in non-liver diseases
- it can be NORMAL in patients with advanced liver DZ
What 3 things is tested in the liver tests?
Liver enzymes (ALT, AST, ALP)
- alanine, aspartate; alk phos [alkaline phosphatase
Protein (Total, albumin/Globulin ratio)
Bilirubin (total and direct)
What are other liver tests that are NOT on the CMP?
CGT, LDH, PT, AFP, urea/ammonia
What are the 4 liver function test CATEGORIES?
- injury to hepatocytes
- capacity to clear endogenous and exogenous substances from circulation
- biosynthetic capacity
- chronic inflammation
What are examples of the liver test for injury to hepatocytes?
Aminotransferases (AST, ALT) LDH
(These are only released from liver cells when there is injury)
What is an example of the liver function testing of capacity to clear end/ex-ogenous substances?
Bilirubin
What are examples of a liver function testing for biosynthetic capacity?
Albumin, prothrombin time (PT)
What are examples of liver function testing for chronic inflammation?
hepatitis serology, immunoglobulins, specific autoantibodies
What is the MOST SENSITIVE indicator for ACUTE hepatocyte injury?
What do they stand for?
AST (aspartate) and ALT (alanine aminotransferase) enzymes
ALT and AST increase ~ 1 week before serum _____?
Bilirubin
When are ALT and AST elevated?
Liver dz
Liver D/O (fatty liver, HF, infxn, metastic carcinoma)
Is ALT or AST related to alcohol associated hepatitis and Cirrhosis?
AST enzyme predominant (aspartate)
What serum amino transferase is highest in concentration in the liver and is the VERY sensitive AND specific for liver disease?
Alanine (ALT) enzyme
What serum amino transferase is highest in concentration in the liver; less specific for liver disease; but predominant in alcoholic hepatitis and cirrhosis?
Aspartate (AST) enzyme
Highest to least concentration of AST within the body?
Liver, Heart, Skeletal muscles, kidneys, brain, pancreas spleen, lungs, WBCs/RBCs
When would AST levels be DECREASED?
Acute renal DZ, beriberi, chronic renal dialysis, Diabetic ketoacidosis, pregnancy
Alk Phos (ALP) is increased highest in?
ALP is also increased in?
- Obstructive biliary dz, bone growth
New bone growth (adolescence, Healing, - osteoblastic metastatic dz)
ALP is the MOST sensitive test for what?
Metastatic Cancer of the Liver
What is measured in Total Protein?
Albumin, non-albumin proteins, and Globulins [antibodies]
What is the function of Albumin?
Why is it a measure of liver biosynthetic ability?
When is albumin markedly decreased?
- maintain intravascular osmotic pressure; transport blood constituents like drugs and hormones
- it is made in the liver
- albumin is markedly decreased in hepatocellular dysfunction
Globulins measured in total protein include what two things?
non-albumin proteins
Alpha, beta, gamma [antibodies]
When dz can total protein be normal but albumin is abnormally lower than globulins?
How?
- Chronic liver dz
- Liver damage = decreased albumin… reticuloendothelial system = more globulins
What is a proper albumin/globulin ratio?
What does an abnormal ration indicate?
- albumin > globulin… ration 1.0+
- decreased albumin suggests albumin targeted dz