Clinical Chemistries: Protein and Hepatobiliary Testing Flashcards
Are protein assays a liver function test?
Not specifically
Two of the three plasma proteins are produced by the liver
What two plasma proteins are produced by the liver?
Albumin and Fibrinogen
Are there other proteins produced by the liver
Yes, they are just in smaller amounts
What are globulins produced by?
The immune system
What are the functions of plasma proteins?
Help form structural matrix of all cells, organs, and tissues Maintain osmotic pressure Serve as enzymes, buffers, and hormones Function in blood coagulation Help with the body's defense system Act as transport or carrier molecules
Total Protein
The total amount of protein in serum
What does total protein measure specifically?
Albumin, globulins, and many other proteins
What is total protein useful in determining?
The hydration status of the patient
Hyperproteinemia
Dehydrated patient
Hypoproteinemia
Over-hydrated or other causes
What protein tests can you run?
Total plasma protein Total Protein Albumin Globulin Fibrinogen
Total plasma protein
Uses plasma and includes all 3 proteins
Can measure with PCV tube and refractometer or
GTT in the analyzer
Albumin
Run in chemistry analyzer
Makes up 35-50% of total protein
Globulin
Rarely done
Estimated by taking the difference between TP and ALB
Fibrinogen
Run with 4 PCV tubes
After spinning, cook 2 in a warm water bath and take the difference on the refractometer
Hypoalbuminemia
Low Albumin
What are the causes of low albumin?
- Liver disease
- Kidney damage
- Malnutrition
- Intestinal disease
- Bloodsucking parasites
How does liver disease cause low albumin?
If the liver is not making adequate amounts
How does kidney damage cause low albumin?
Proteins are leaking through a damaged glomerulus
How does intestinal disease cause low albumin
Prevents the absorption of proteins
High Albumin =
Usually dehydration
Why is the albumin/globulin ratio important?
Because it is the first indication of a protein abnormality
What is the albumin/globulin ratio analyzed in conjunction with?
The protein profile
What alters the albumin/globulin ratio?
Most pathologic conditions
What condition does not alter the albumin/globulin ratio and why?
Hemorrhage because everything is reduced in equal amounts
Fibrinogen
Only when you have plasma
Produced by the liver
What percent does fibrinogen make up in the total plasma protein?
3 to 6%
What happens if fibrinogen is low?
Blood will not clot normally
What causes high fibrinogen?
Inflammation or tissue damage
What phase is clotting involved in
Mechanical phase
Platelets and smooth muscle contraction
What phase is the clotting cascade apart of?
Chemical phase
Fibrinogen gets converted into insoluble fibrin
