7 Reasons Your Dog’s White Blood Cell Count Is High

Quick Take

• One cause of high white blood cell counts has nothing to do with illness, and your vet's office might actually be what triggers it. Stress responses explained →
• Not all white blood cells react to the same threat, so which type is elevated tells your vet something very specific about what's wrong. See the five cell types →
• A high white blood cell count can sometimes signal something as minor as an ear infection, and other times something as serious as cancer. See all seven causes →
• Chronic conditions you're already managing could be secretly driving your dog's abnormal blood results without you realizing it. Chronic inflammation effects →

Has your vet told you that your dog has an elevated white blood cell count on their recent blood tests? To better understand what this might mean for your canine friend, learn more about the most common causes of high white blood cell counts in dogs and what you can do about it.

What Are White Blood Cells?

The main purpose of white blood cells in dogs is to aid in fighting infection. There are two main forms of white blood cell that aid in the fight against infection, and this includes phagocytes and lymphocytes. Phagocytes are responsible for chewing up any invading organisms in the body, while the lymphocytes remember the organism to then destroy it in the future.

There are five types of white blood cells found in dogs. These include neutrophils, lymphocytes, monocytes, eosinophils, and basophils. While each of these work together to protect the body against infection, they have individual issues they target. For example, you will often see elevated neutrophils when there is a bacterial infection or inflammation present in the body, while high levels of lymphocytes often point to a viral infection or other immune stimulation.

How to Check Your Dog’s White Blood Cell Count

The only way to determine your dog’s white blood cell count is to have blood tests performed at your vet’s office. A complete blood count (CBC) will offer you insight into your dog’s red blood cell and white blood cell counts, allowing your vet to analyze the results and determine the best plan of action. Your vet can typically perform these blood tests in their clinic, or they can send your dog’s blood sample to a nearby lab if they don’t have the necessary equipment.

7 Reasons Dogs Have A High White Blood Cell Count

There are seven potential reasons why your dog has an elevated white blood cell count on their blood tests. Take an in-depth look at each of these reasons in the following sections.

#1. Infection

An infection is one of the most common causes of an elevated white blood cell count in dogs. These infections can be bacterial, viral, or fungal in nature, and they can impact any region of the body. Some of the most common infections seen in dogs include urinary tract infections, ear infections, gastrointestinal infections, dental infections, and skin infections.

#2. Parasites

Parasites of the digestive system, skin, or cardiovascular system can also cause an elevated high white blood cell count in dogs. Some of the most common forms of parasites seen in dogs include intestinal parasites, fleas, and even heartworms. Eosinophils and basophils are often most elevated when dealing with parasitic infections, but all white blood cells may be affected.

#3. Allergies

Chronic allergies can cause a high white blood cell count in dogs. Canine allergies cause an inflammatory response that often leads to itchy skin and secondary infections, each of which can lead to an increased white blood cell count. This is especially true in dogs that have unmanaged canine allergies.

#4. Inflammation

Inflammation can also cause high white blood cell count in dogs. This can occur in a variety of chronic inflammatory illnesses, but one of the most common contributing factors is arthritis. The constant inflammation and joint breakdown can impact the white blood cells over time, especially if the dog is not on a joint care plan.

#5. Stress

Stress can lead to a slight elevation in a dog’s white blood cell count. For example, if a nervous dog comes into the hospital for annual blood tests, it is not uncommon to see a slight elevation in their neutrophil count due to the stress of their visit. Stress could be the underlying factor if your vet cannot find any other cause of their elevated white blood cell count.

#6. Autoimmune Disorders

Autoimmune conditions can cause an elevated white blood cell count in dogs. Many of these conditions cause inflammation and destruction of tissue, so it makes sense that the white blood cell count would be affected. Some of the most common autoimmune disorders seen in dogs include inflammatory bowel disease, immune-mediated hemolytic anemia, Addison’s disease, hypothyroidism, and rheumatoid arthritis.

#7. Cancer

Some forms of cancer can cause an increased white blood cell count in dogs. The most common forms of cancer in dogs that cause an elevated white blood cell count are leukemia and lymphoma. A high white blood cell count does not mean your dog has cancer, and other potential factors on this list are much more likely. However, your vet will always try to rule out the possibility of cancer when your dog has abnormal blood test results.

How to Fix A High White Blood Cell Count In Dogs

You may be wondering what to do next if you just found out that your dog has an elevated white blood cell count. As you can see from our discussion above, a high white blood cell count in dogs can be due to a variety of underlying factors. It is best to trust your vet’s guidance on how to treat your pup moving forward.

Treatment for your dog’s elevated white blood cell count could involve antibiotics to treat an infection, inflammation control to manage their chronic joint condition, allergy management, and even aggressive medical care for autoimmune conditions or cancer. Each of these medical conditions require an entirely different treatment protocol, which is why it is essential to follow your vet’s guidance on what to do next. Your vet is the only one that understands the details of your pet’s case and their blood test results, so they will know how to best proceed.