1. Chapter 45
Diagnostic Testing

2. Quality Control
Quality control and assurance are important to the integrity of test results
Perform controls:
At the beginning of each day
When opening a new bottle of reagent strips

3. Quality Control Document the following in the log book: Date
Patient’s name
Test performed
Results of test
Your initials
Kit, reagent strip, lot numbers, expiration dates
Quality control results

4. Hematology Testing Hemoglobin and hematocrit
Screening tests that require a small amount of blood
Usually obtained through a capillary puncture
Hematocrit may use either capillary blood or venous blood

5. Hemoglobin Hemoglobin is essential to oxygen circulation in the body
Normal ranges
Males: g/dL
Females: g/dL

6. Hematocrit Screens for anemia Normal ranges Males: 40-54%
Females: 37-47%

7. Complete Blood Count
Common test ordered in provider’s office, which measures many values
Total red blood cell count
Total granulocyte count
Total white blood cell count
Total lymphocyte and monocyte count
Total platelet count
Percentage of granulocytes
Hemoglobin
Percentage of lymphocytes and monocytes
Hematocrit
Red blood cell indices

8. WBC Differential Performed on 100 white blood cells
Numbers of neutrophils, eosinophils, basophils, monocytes, and lymphocytes counted
Physicians review for abnormalities of the red blood cells
MAs do not perform these counts, but should be familiar with the reports

9. ESR
Rate at which red blood cells settle in a calibrated tube within a given time
Determines how much inflammation is occurring in response to another disease condition
Two methods
Westergren
Wintrobe

10. Glucose Testing Capillary blood samples usually used
Handheld meter with reagent strips
Perform quality controls
At the beginning of each day
When opening a new package of reagent strips
Log results prior to reporting patient results

11. Glucose Tolerance Testing
Performed when patient has consistently high fasting blood sugar
To help provider make a diagnosis of diabetes mellitus or hypoglycemia
Determines the patient’s ability to metabolize a glucose load over a prescribed amount of time

12. Hemoglobin A1C Modified form of hemoglobin
Helps determine how the diabetic patient has been controlling blood sugar over 2-3 months
Often ordered with random blood sugar level

13. Immunology
The study of the body’s ability to prevent and fight off infection
Immunoassays are diagnostic tests that measure the amount of antigens and antibodies present relative to an illness

14. Mononucleosis Testing
Illness causes by the Epstein Barr virus
Symptoms similar to the flu
Extremely contagious
Most common in individuals years old
Immunoassay detects the presence or absence of the antibodies to EBV

15. Allergy Testing
This type of testing involves introducing an antigen directly into the patient’s skin to induce a reaction
If the reaction is negative (normal), there will be no change in the skin
If the reaction is positive, a wheal will develop on the skin

16. Allergy Testing Skin prick tests Intradermal injections
Allergen is applied directly to patient’s skin and scratched or “pricked” into the epidermis
Intradermal injections
Allergen is injected between the epidermis and dermis

17. Allergy Testing Skin patch tests RAST
Allergen-soaked pad is applied to the surface of the skin for hours
RAST
Determines the presence of immunoglobulins
Test given when individuals cannot tolerate skin tests

18. Allergy Testing Nasal smears Aids in the diagnosis of allergies
Smear done with nasal secretions
Provider observes the eosinophil count

19. HIV Testing Standard screening tests are enzyme immunoassays
May have to draw blood for this screening
Follow policy and procedure for collection as well as standard precautions

20. PKU Testing Screening test done on infants using capillary blood
Drops of blood are soaked through outlined circles on PKU testing card and attached to requisition
The card and form are send to state health department for processing
Required in all states and Canada

21. Testing Outside the POL
Series of tests ordered are done as panels or profiles
Panels are less expensive than individual tests
MA responsibilities
Prepare specimen for sending
Screen test results as they are returned to provider’s office
Immediately follow-up panic values