1. Diagnostic Blood Tests
Danya, Steven, Runyang, Sabih
September 17, 2019
PHM Fall 2019
Instructor: Chesa Dojo Soeandy
Coordinator: Jeffrey Henderson

2. What is a Blood Test?
“Any test designed to discover abnormalities in a sample of a person’s blood”
Evaluate organs
Diagnose diseases
Find risk factors
Test blood clotting
Effectiveness of drugs
By definition, a blood test is any test designed to discover abnormalities in a sample of a person’s blood
Used to evaluate how well organs are working, such as the liver, kidneys, thyroid and heart
Diagnose diseases such as cancer, HIV/AIDS, diabetes, anemia and heart diseases
Find out whether you have risk factors for certain diseases, such as heart disease
Check whether the medications you are taking are working
Can also be used to assess how well a person’s blood is clotting
Most of the blood tests do not need preparations, but it is very common that you fast before your test if you want to test your blood glucose level for conditions like diabetes

3. How does a Blood Test Work?
Diet
Stress
Medication use
Alcohol
Exercise
To begin, you obviously have to draw blood
The most common place that blood is drawn from is the vein
Blood is then put into a centrifuge and spun until the different components separate into different layers
The different layers are the hematocrit, buffy coat, and plasma
Hematocrit: red blood cells
Buffy coat: white blood cells, platelets
Plasma: water, proteins, nutrients, hormones, etc
Using complex formulas, the amount of each substance is calculated and then compared to a reference range
The reference range is the range of expected values for each test listed
A number above or below this reference range can give valuable diagnostic information about the body and certain symptoms
It is important to note that blood test results will vary depending on things like:
Time of the year, Diet, Stress, Medication use, Alcohol, Exercise

4. What do they Measure? Hematology Blood Glucose Cholesterol
RBC
WBC
Platelets
Hemoglobin
Hematocrit
Mean Corpuscular Volume (MCV)
Blood Glucose
Cholesterol
Vitamins and Minerals
So what does a blood test specifically measure?
on a typical blood test report, you will find measurements for hematology, which is basically you full blood count that includes RBC, WBC, platelets, hemoglobin, hematocrit, and mean corpuscular volume (abbreviated as MCV)
You will also find blood glucose, which is measured under fasting conditions
Cholesterol, and vitamins and minerals

5. What do the Results mean?
Blood Test
Normal Results
**may change with age or race
Diagnostic
Red Blood Cell Count
Male: 5 to 6 million cells/mcL
Female: 4 to 5 million cells/mCL
Abnormal levels may indicate disease such as anemia (too low) or polycythemia vera (too many)
Mean Corpuscular Volume (MCV)
80 to 95 femtoliter
Larger cells:
Vitamin B12 deficiency
Liver disease
Smaller cells:
Iron-deficiency anemia
Thalassemia
Blood Glucose
70-99 mg/dL
mg/dL - prediabetes
>126 mg/dL - diabetes
Lipoprotein Panel
Total cholesterol
LDL cholesterol
HDL cholesterol
Total: < 200mg/dL
LDL: < 100mg/dL
HDL: 40-59mg/dL
Higher blood cholesterol can lead to higher risk of atherosclerosis
HDL: > 60 mg/dL reduces risk of heart disease
-Abnormal levels may not always indicate disease, abnormal results can be caused by factors such as diet or smoking
- Please note that blood tests cannot be the only tool for diagnosing diseases, it is usually paired with other diagnostic tests
- atherosclerosis - plaque build up in the arteries
Total cholestrol includes HDL, LDL, and VLDL cholestrol

6. Blood Test Results Example
Danya’s Blood Test
How to read results
Reference range
Attention
What can you infer from the results?
Microcytosis: MCV < 70 fl in adults
Thalassemia or Iron Deficiency
Cold/Getting over a cold
Thalassemia is a blood disorder passed down through families (inherited) in which the body makes an abnormal form or inadequate amount of hemoglobin.
I actually got another blood test done about a week and a half after the first and confirmed that I still had microcytosis

7. Looking at the whole picture
Not technically anemic
But if I was anemic, thalassemia would explain why I would be anemic

8. Assessing Heart Disease Risk
Patient at risk for Heart Disease
Test Name
mmol/L
LDL Cholesterol
10.25
HDL Cholesterol
3.6
Cholesterol
14.7
If you have too much cholesterol in your body, it can build up in the walls of your arteries (as "plaque") and eventually harden.
High cholesterol doesn’t cause symptoms until it’s too late -- so better to check early & see if you’re at risk
Cholesterol high risk: above 13 mmol/L
LDL: above 10 mmol/L
HDL is good fats, generally want this to be high
Photo:

9. Summary
“Any test designed to discover abnormalities in a sample of a person’s blood”
Useful for:
Evaluating organ health
Diagnosing diseases and conditions
Checking for any risk factors for diseases
Assessing if medicines are working
Commonly used to measure:
Hematology
Includes: red blood cells, white blood cells, platelets, hemoglobin, hematocrit, and mean corpuscular volume
Blood glucose
Lipoprotein Panel (HDL and LDL cholesterol levels)

10. References
Blood Tests.
Overview of Blood Tests.
Blood Test and Lab Analysis.
Blood Tests MCV and MCHC.