Clinical Blood Tests Flashcards
What makes up the “buffy coat” in a whole blood sample that has been centrifuged?
Leukocytes and Platelets
What makes up plasma?
Whole blood without:
RBCs
WBCs
Platelets
What makes up serum
Plasma without:
Fibrinogen
Clotting factors
What is included in a basic electrolyte panel?
Na
K
Cl
HCO3-
What is included in a basic metabolic profile?
Electrolyte panel \+ glucose BUN Creatinine (for kidney function)
Main use for a comprehensive metabolic panel.
Liver function in addition to kidney function
Normal BUN:Creatinine ratio
10-20:1
What does an elevated BUN:Cr indicate?
Prerenal disease
What does a decreased BUN:Cr indicate?
Postrenal disease or obstruction
Major medication class that can skew a fasting glucose test
Steroids
How is corrected calcium calculated?
0.8(normal albumin-measured albumin) + serum calcium
For every 1g albumin is low, calcium should be 0.8g low
Used when albumin levels are less than 4g/dL
3 primary sources of alkaline phosphatase
Bone, liver, placenta
What distinguishes which source of alkaline phosphatase causes a rise in the enzyme serum concentration?
Bone: usually in children
Liver: check Gamma-Glutamyl Transpeptidase (GGTP) levels, if they are elevated it’s the liver
Placenta: pregnant patients
What can cause an elevation in unconjugated serum bilirubin?
Genetic disease in the neonatal period.
What can cause an elevation in conjugated serum bilirubin?
Alcoholism
Gallstones
When is an HbA1c test ordered?
To check for diabetes diagnosis in patients with borderline serum glucose levels.
To monitor patients already diagnosed with diabetes
Enzyme measured that is very specific for cardiac injury.
Troponin I
What can a Thyrotropin test be used for?
TSH test
- elevated TSH indicates hypothyroidism
- depressed TSH can indicate hyperthyroidism
When is a free Thyroxine (T4) test used?
confirms a TSH test.
T4 is a product of the thyroid (it is thyroid hormone)
-if TSH is low and T4 is high = hyperthyroidism
-if TSH is high and T4 is low = hypothyroidism
When are tumor marker tests most effective in regards to cancer diagnosis?
They are not used to diagnose cancer very often, they are mainly used to monitor already diagnosed cancers.
(Alpha-Fetoprotein and Prostate Specific antigen are more specific and may be used for diagnosis)
What does a CBC with differential include that a standard CBC does not?
WBC count
What do “Band neutrophils” often indicate?
They are immature neutrophils seen on blood smear. When in high levels, they often indicate rapidly producing WBCs in response to:
infection or
myeloproliferative disease
What do the terms anisocytosis and poikilocytosis indicate?
Anisocytosis: RBCs varying in size
Poikilocytosis: RBCs varying in shape
What does a low ferritin level indicate?
Not only is the patient iron deficient, they have been chronically iron deficient
What measures Total Iron binding capacity?
Transferrin levels
What does a reticulocyte count measure?
Erythropoetic activity of bone marrow
What does a Partial Thromboplastin Time measure?
Clotting of the Intrinsic Pathway for Heparin monitoring
Why is the International Normalized Ratio used?
Used for Warfarin monitoring
INR = Patient’s PT time/ Normal PT time
What 3 things are elevated in urinalysis in patients with a UTI?
Leukocytes
Nitrite
Blood
