I have to admit, I’m a little bit of a microscope geek. Although I don’t claim to be any better than fellow classmates at finding and identifying things under the microscope lens, I do claim to be one of the most enthusiastic. For some reason it’s very satisfying to find weird looking things under the microscope, whether it’s Giardia trophozoites on a fecal smear, bilirubin crystals or white blood cells on a urine sediment, or yeast and bacterial cocci on an ear smear.
Since starting clinical pathology, I’ve loved the opportunity to look at multiple blood smears, both normal and abnormal. For example, during one lab we practiced doing a manual differential white blood cell count, which simply means that we counted 100 WBCs, keeping track of how many of each cell type there was (eg, 68 neutrophils, 15 lymphocytes, 13 monocytes, 4 eosinophils). This is good for determining the percentage of each cell type present, and it also lets us look at cell appearance (morphology). I thought it was super cool to see the red granules of eosinophils in person, and to try to decide if a neutrophil had toxic changes. I also felt much more confident about telling monocytes apart from neutrophils, after being able to view several dozen of them.
In a second lab, we learned how anemic red blood cells look different from normal RBCs (hint: they’re often larger and more bluish purple than red!). It was cool to take a look at the oval nucleated RBCs of a turtle, and a blood smear from a llama infected with Mycoplasma hemollamae. There’s just something about being able to zoom in and out on your own that helps you see and remember things better than simply viewing a Powerpoint slide!