Splenomegaly is the official medical term for an enlarged spleen in dogs and humans and it is a common condition that can affect dogs of all ages, sizes, breeds and genders. However, it tends to be more commonly diagnosed in middle-aged dogs. Read on to learn more about the spleen and how splenomegaly can affect your dog.
All About the Dog Spleen
Just like humans, dogs have lymphatic systems that filter their blood, remove damaged red blood cells and balance the fluids in their body. The spleen is the largest organ in the lymphatic system. In dogs, the spleen lives in the abdominal cavity, snuggled up under the rib cage on the left side of the abdomen alongside the stomach.
A normal, healthy spleen looks like a small, purple, soft and squishy boomerang. Its many blood vessels attach it to the liver and the stomach, and the blood supply of these three organs is closely tied together.
The spleen has two main functions: removing old red blood cells and helping the immune system fight off infections. Both of these functions are very important to keeping your dog healthy. Thankfully, if your dog ever has to have their spleen removed, the body has protective mechanisms in place to ensure these functions can be carried out by other organs in the body.
Causes of an Enlarged Spleen in a Dog
Splenomegaly in dogs can occur for multiple reasons, including:
- Infections, such as liver infections (also known as hepatitis), intestinal or stomach infections and bloodborne infections.
- Inflammation in the gut due to IBD (inflammatory bowel disease (Source: 5 minute Veterinary Consult, Sixth Edition))
- Tumors, both benign and malignant.
- Abdominal injuries, such as those sustained from being hit by a car or kicked by a horse.
The main concern with enlarged spleens is that they are at an increased risk for injury and rupture, which can cause massive and potentially life-threatening abdominal bleeding in a dog, according to Wag!. Although there is no way to completely prevent an enlarged spleen, having your dog checked out yearly by a veterinarian can help you catch any problems early on.
Symptoms
The signs of an enlarged spleen in dogs depend on how big the spleen becomes. Also, if the spleen is ruptured and bleeding and then how much, how fast, or how long the spleen has been bleeding. All of these factors will significantly impact how sick your dog acts. Symptoms of an acutely ruptured and actively bleeding spleen can include:
- Sudden lethargy
- Pale gums
- Appetite loss
- Enlarged, potbelly abdomen
- Sudden weakness or collapse
- Racing heart rate
- Panting
Dog spleens that are damaged from an injury or cancer may not be easily noticeable, and they can bleed small amounts over a long period of time. Dogs with a damaged spleen may look and behave completely normal even if they are slightly anemic, meaning they have a lower than normal red blood cell count.
If your dog has cancer, an infection or inflammatory bowel disease, they may also experience symptoms associated with these conditions, such as fever, weight loss, vomiting and diarrhea.