In the previous post, I was going on and on about how important blood tests are. I use the term “blood test” as a blanket term, because really, there are plenty of different blood tests, from doing bacteria cultures to testing your blood sugar level. Most of the time, you’ll get something called “Cbc and Auto Diff” (complete blood count and automated differential). It is a rather broad test that can screen for diseases, see if certain conditions like anemia are present, and it can tell you how effective your treatment is. Growing up, doctors were rather reluctant to provide my parents and me with the exact results of the blood tests. We’d get information as “it looks a bit better now”- very exact, right? Doctor-patient relations have come a long, long way since then, and now, I have access to my files, and can see my blood test results. This however means that the burden of informing yourself, is on you.
So this is what one of these test results look like (it’s actually only half), taken in February 2015. The middle column are my results, and the right column is what is considered a “normal range.” I’ll go through the most important ones.
White Cell count– white blood cells are also called leukozytes, and you can think of them as the body’s first response to inflammation, allergies, infections- you name it. This means, that they get easily elevated, too, making them a rather rough indicator that something’s wrong. Still, if there is something, they are up.
Red Blood Cell Count- They are also called erythrocytes, and they are the ones carrying oxygen into the cells. “RBCs typically make up about 40% of the blood volume(…). The typical lifespan of an RBC is 120 days; thus the bone marrow must continually produce new RBCs to replace those that age and degrade or are lost through bleeding. There are a number of conditions that can affect the production of new RBCs and/or their lifespan, in addition to those conditions that may result in significant bleeding.”(1) So, in my little sample, they are fairly low, mostly because this was after surgery number 3 in 30 days, so not long enough to get re-produced.
Hemoglobin- Red blood cells contain hemoglobin, a protein that binds to oxygen and enables RBCs to carry oxygen from the lungs to the tissues and organs of the body. So, together with a low RBC count, a low hemoglobin rate shows that there is either an iron deficiency, you have an internal bleeding, ding ding- Anemia.
Hematocrit finishes off the holy trinity of red blood cells- it tells you the percentage of red blood cells vs plasma vs white blood cells. So if your hematocrit is low, your hemoglobin is low, it’s bad news.
MCV– Mean corpuscular volume looks at the average size of a red blood cell. If anemia is suspected, then this will hint at what kind of anemia we are looking at (iron deficiency anemia, or thalassemia vs. B12 deficiency anemia).
MCH– Mean corpuscular hemoglobin, this looks at the average size of the hemoglobin proteins.
RDW- this is a calculation of the variation in size of the red blood cells.
Platelets- also called thrombocytes. These are little fragments of cells that take care of blood clotting. Low platelets can indicate a wide range of conditions from bleeding disorder, gastrointestinal bleeding, to leukemia and bone marrow problems.
MPV– Mean platelet volume “indicates average size of platelets is small; older platelets are generally smaller than younger ones and a low MPV may mean that a condition is affecting the production of platelets by the bone marrow.” (2)
It is mind boggling to me how much can be tested for, I mean, average size of platelets??! And still, it can be deceptive-considering that this test was done right after a sepsis, it looks pretty good! Likewise, when I look at old, old blood tests from when I was a child, where my white count used to spike up at the smallest inflammation. In short- a blood test on its own will give you a rough idea that something is wrong (or that nothing is wrong!). If something is off, your doctor will order further tests to see what’s going on.
(1) and (2): https://labtestsonline.org/
A wonderful resource!