Diagnostic Blood Tests Danya, Steven, Runyang, Sabih September 17, 2019 PHM142 Fall 2019 Instructor: Chesa Dojo Soeandy Coordinator: Jeffrey Henderson

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 https://www.precisionnutrition.com/all-about-blood-work https://www.nhlbi.nih.gov/health-topics/blood-tests

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 https://www.nhs.uk/conditions/blood-tests/ https://www.medicine.mcgill.ca/physio/vlab/bloodlab/mcv-mchc_n.htm

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

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 100-125 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 https://www.nhlbi.nih.gov/health-topics/blood-tests Total cholestrol includes HDL, LDL, and VLDL cholestrol

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

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

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: https://drparrsays.com/2015/02/16/numbers-you-need-to-know-to-prevent-and-treat-heart-disease/

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) https://www.nhlbi.nih.gov/health-topics/blood-tests

References Blood Tests. https://www.nhlbi.nih.gov/health-topics/blood-tests Overview of Blood Tests. https://www.nhs.uk/conditions/blood-tests/ Blood Test and Lab Analysis. https://www.precisionnutrition.com/all-about-blood-work Blood Tests MCV and MCHC. https://www.medicine.mcgill.ca/physio/vlab/bloodlab/mcv-mchc_n.htm