Saturday, January 15, 2011
Fun-a-day 15: Veterinary Medicine, Heartworm
One thing medical technology school didn't teach me, and that surprised me when I first started work, was that many medical labs also do veterinary testing. Animals get sick too, after all, and lab tests, like chemistry panels, and complete blood counts can help the veterinarian diagnose and treat our pets and livestock.
Heart worm is another mosquito-borne parasite that can be seen in the animal's blood. It was something that we would occasionally see on a blood smear. They're quite big, and it doesn't take too much imagination to see how this would cause problems for the animal. As with other parasitic infections, often there would be an increased number of eosinophils in the blood. Once again, these are white blood cells that help fight infection, and "specialize" in parasitic infections, as well as allergy response. The "worm" on the quilt block is a "microfilaria". The orange cells are the eosinophils. I put red blood cells and a lymphocyte on it as well for fun.
Surprisingly, dog blood appears very similar to people blood when viewed under a microscope. One of my favorite "lab party tricks" was to take the "fresh" blood out of the test tube from an infected dog and view it under low power as a wet prep. These microfilaria often would still be alive and we could watch them move around. I know, it's a bit warped, but we had to do something in the lab to entertain ourselves...
There are a very few parasites that will form microfilaria in human blood, but luckily I've never seen these. I think Loa loa (found in Africa) is one of them, but don't quote me on that. It's been a while since I had parasitology!
Luckily there is prevention and treatment for dogs who get heart worm. In fact our family pet dog growing up was infected when we brought him home from the pound, and recovered to live a long and happy life.