Immune-Mediated Hemolytic Anemia: What Dog Owners Need to Know
As a pet owner, nothing is as scary as a disease that can take our pets from us without warning, and sometimes even without cause. Immune-mediated hemolytic anemia (IMHA) is a condition that can do just that, though.
Although you’ve likely never heard of it, it’s important to learn what you need to know so that if you ever have a pet who is affected by IMHA you can take prompt and effective action.
What is Immune-Mediated Hemolytic Anemia in Dogs?
The name of the disease says it all. In pets affected by IMHA the immune system begins to destroy (hemolyze) the animal’s own red blood cells, resulting in anemia.
In IMHA the pet’s antibodies begin to attack the red blood cells in the bloodstream. These cells become coated with antibody, targeting them for destruction. The body then lyses, or pops, these red blood cells, removing them from circulation.
Because red blood cells are important for transporting oxygen throughout the body, when a pet has too few red blood cells, he or she essentially becomes oxygen-deprived. The spleen and liver, which normally help to clean up old red blood cells, also become overwhelmed.
What are the Symptoms of Immune-Mediated Hemolytic Anemia?
Because patients with IMHA are suffering from a low red blood cell count, often pet owners will notice:
- Weakness
- Lethargy or depression
- Decreased appetite
- Dark orange to brown urine
- Pale to yellow skin/gums
- Jaundice (yellow discoloration, especially of the whites of the eyes)
- Sometimes fever
Any time a pet is exhibiting these symptoms, it is important to have him or her evaluated right away. IMHA in particular can come on and progress very rapidly. While none of these are unique to IMHA, they can all be signs of a serious problem.
What Causes Immune-Mediated Hemolytic Anemia in Dogs?
Anything that stimulates the immune system can trigger IMHA. This can be an infection, a bug bite, or even a vaccine. In about 60-75% of cases, however, the cause of the immune reaction remains unknown.
Certain breeds also seem prone to developing IMHA. These include:
- Cocker Spaniels
- Irish Setters
- Old English Sheep Dogs
How is Immune-Mediated Hemolytic Anemia Treated?
Aggressive treatment is required for patients who develop IMHA. Treatment is aimed at three goals:
Removing the inciting cause – While most cases of IMHA do not have an identifiable cause, it is important to remove the cause if one is present. Pets who develop IMHA often need to have extensive diagnostic tests performed in order to look for any problems that need treated.
Stopping the immune reaction – Obviously, stopping the abnormal immune response is key to success. This is most often accomplished through the use of corticosteroids such as prednisone. Sometimes supplemental immunosuppressive drugs are needed as well.
Providing supportive care – Stopping the immune reaction is not instant, and it takes the body time to recover. During treatment patients often need to receive one or more blood transfusions to help them recover. Many IMHA patients are in critical condition and require hospitalization.
Immune-mediated hemolytic anemia is a very serious condition and requires aggressive treatment. Even despite excellent care, some patients still do not survive. It is very important for pet owners to recognize the signs of IMHA so that in the event their pet is affected they can provide care early in the course of the disease. As with so many conditions we see, catching problems early in their process is key to success.
