An enlarged spleen is known as splenomegaly. This is not a disease; it is a clinical sign of some underlying disease process. The spleen has a number of functions that include:
- Removal of cell fragments and old or damaged red blood cells
- Holding tank for specialized white blood cells that aid in the cleanup of bacterial infections
- Antibody manufacturing
- Production of red blood cells and storage of blood
The fact that your dog’s spleen has several functions makes for several possibilities as to why the spleen can become enlarged.
Signs & Symptoms of Enlarged Spleen
An enlarged spleen may lead to such symptoms as:
- Lack of appetite
- Abdominal pain
- Lethargy and reduced activity
- Weakness and even collapse
- An appearance of discomfort when attempting activities
- Bloating of abdomen
Causes of Enlarged Spleen
As mentioned above, there are many causes of splenomegaly. Some of the causes for an enlarged spleen in your dog are:
- Bacterial, fungal, and parasitic infections that are affecting other organs may affect the spleen as well and cause splenic enlargement.
- Any diseases that cause destruction of red or white blood cells and/or platelets. For instance anemia, leukopenia, and thrombocytopenia.
- Congestive heart failure can lead to splenic enlargement.
- Circumstances that lead to high blood pressure involving the venous system.
- Bleeding and hematoma formation (bruising) in the spleen.
- Tumors like hemangioma and hemangiosarcoma.
- Splenic torsion
For these reasons it is important for your veterinarian to run a variety of diagnostic tests in order to narrow the diagnosis field.
Diagnosis of Enlarged Spleen
Diagnosis begins with a complete history and a physical exam. The diagnostic path chosen will depend largely on the symptoms your dog has, and the availability of diagnostic tools your veterinarian has. Your veterinarian will be most likely to recommend some variation of the following:
- Upon exam, the spleen is palpated (examined by touch) to determine size and shape.
- CBC/Chemistry Panel - This blood test evaluates internal organ function, status of infection, electrolyte balance, and blood cell counts.
- Coagulation profile - This blood test evaluates your dog’s clot forming ability. A common tumor of the spleen (hemangiosarcoma) is related to this blood function.
- Urinalysis - This test will reveal the presence of red or white blood cells that indicate inflammation and/or infection. This test is normally used in a much broader scope, but for enlarged spleens your veterinarian will be looking more specifically for blood present in the urine as a diagnostic indicator.
- Radiographs (x-rays) - Radiographs may be taken and are used to evaluate the appearance of the spleen and other related abdominal organs.
- Abdominal Ultrasound - An ultrasound of the spleen will help your veterinarian determine if there are tumors present on the spleen, and of course this also provides a medium for evaluation of the size of spleen.
- Fine needle (splenic) aspirate - A needle is inserted into the spleen and cells are removed. These cells undergo a cytological evaluation and can help determine the type of splenic disease that is present.
Treatment for Enlarged Spleen
The treatment plan for an enlarged spleen can vary. The ultimate decision will come down to test results that reveal the underlying process that is causing your dog’s spleen to be enlarged. Your veterinarian will most likely recommend one of the following treatment options available for splenomegaly:
- Splenectomy - Surgical removal of the spleen; still the most common treatment plan.
- Medications and supportive care - Based on the clinical findings, broad-spectrum antibiotics and treatment of symptoms may be a part of the treatment plan.
Prevention of Enlarged Spleen
There are currently no known preventive measures for an enlarged spleen in dogs.