A couple of weeks ago, I wrote about a stray, flea-infested black kitten who found her way to the ER at the Schwarzman Animal Medical Center just in time for a life-saving blood transfusion. While they say lighting doesn’t strike the same place twice, it happened again last week at the AMC ER—another youngster in need of a blood transfusion. The protagonist of this blogpost is a 10-week-old puppy, admitted for severe anemia.
Anemia Definition
Anemia means there are not enough red blood cells in the blood vessels. Since red blood cells deliver oxygen throughout the body, every organ suffers. Anemia occurs for three main reasons:
Blood loss from an external injury or internal bleeding or blood sucking parasites
Decreased production of red blood cells by the bone marrow
Destruction of the red blood cells by a medication, heatstroke or immune disorder
For otherwise healthy youngsters like this border collie, we worry about an intestinal parasite infestation causing anemia.
Blood Loss from Intestinal Parasites
Puppies and kittens are particularly susceptible to blood loss because of their small size. A few fleas or a couple of intestinal worms don’t do much damage to an adult dog or cat but, as we learned in the black kitten’s story, a few fleas can be life-threatening in a small puppy or kitten. Intestinal worms, like hookworms, feed on blood from the walls of the small intestines. The worms also leave bleeding ulcers at the site where they attach themselves to the intestinal wall to feed. The worms are only 1/8 of an inch long and hard to see with the naked eye. Despite their tiny size, they are prolific blood suckers, each consuming 0.1 ml in 24 hours. An infestation of 100-500 hookworms would consume 2-10 teaspoons of blood a day, or roughly 2-12% of our 11-pound puppy’s entire blood supply. These numbers vary with the size of the animal and the severity of the infection, but you can clearly see how devastating this parasite can be in a small puppy.
Hookworm Biology
Hookworms can live for months in the intestine of a dog. Mother dogs with hookworms can transmit them through their milk to the puppies. This explains why we deworm puppies at every vaccination visit and why monthly parasite prevention medications contain drugs active against hookworms and other intestinal parasites.
Dogs infected with hookworms will shed hookworm eggs in the stool. That’s how this puppy’s medical team made the diagnosis of hookworm anemia: they viewed a stool sample using a microscope and found the hookworm eggs. In the United States, hookworms are becoming resistant to many of the anti-hookworm drugs available to veterinarians. If your veterinarian suspects resistance, additional testing may be required.
A Tiny Transfusion for a Tiny Patient
This puppy weighed just 11 pounds. Such a little patient needs only a little blood. In this case, the transfusion was only three tablespoons of blood. Such a small amount of blood hardly seems like it would make a difference, but the blood and a deworming medicine made a huge difference. When this puppy was admitted to the ER, he was barely responsive and, when I went to visit the little guy the next day, he was a wild man—wagging, jumping and acting like a normal puppy.
All’s Well That Ends Well
Like the black kitten story, this one has a happy ending. Our fluffy puppy patient returned to AMC several days later for a recheck and was given the all clear by his AMC medical team.