Enlarged lymph nodes in dogs may be due to several health conditions from a simple infection to cancer. The lymph nodes are glands that filter the blood and store the white blood cells. The lymph nodes can get swollen as a response to any inflammation in the body. There are several lymph nodes located in various areas of the body (i.e. the neck, close to the front legs). When the lymph nodes in an area are swollen, this indicates an infection that is in the nearby area.
Causes of Enlarged Lymph Nodes
The lymph nodes can get enlarged when there is an infection in the body; this is due to the fact that the white blood cell count is increased.
The enlarged lymph nodes also known as lymphadenitis can be caused by:
- Viral, fungal or bacterial infections
- Injuries or lesions of the lymph nodes
- Allergic reactions to various environmental factors such as chemicals; the immune system will produce inflammatory cells which can affect the lymph nodes
- Immune system diseases, which can result in the secretion of inflammatory cells
- The presence of cancerous cells, which may affect the lymph nodes or originate in a different area of the body
- Leukemia (cancer of the blood)
- Bone marrow infection
- Asthma
- Idiopathic causes
Additional Symptoms
When the lymph nodes are swollen, these can be detected by palpating the dog’s body.
The lymph nodes can be felt under the jaw and around the shoulder area.
In addition to the swelling, there may be additional symptoms such as:
- Swollen frontal legs
- Lethargy
- Constipation or diarrhea
- Lack of appetite
- Vomiting
- Breathing problems
These symptoms may be indicative of a number of diseases, so the dog should be consulted by a vet.
Diagnosing Enlarged Lymph Nodes in Dogs
To properly diagnose the dog and determine the cause of the enlarged lymph nodes, the vet will have to perform a series of tests such as:
- Complete blood count
- Urine test
- Lymph node aspirates, which will be examined to determine if the dog is affected by cancer or a type of infection
- X-rays and ultrasounds
- Biopsy of possible growth detected
- Intradermal testing for allergic reactions
Treatment Options
The enlarged lymph nodes treatment options will vary according to the condition causing the swelling.
The treatment may involve:
- Medication treatment for infections
- Antihistamines and steroids for allergic reactions or asthma outbreaks
- Corticosteroids for immune system mediated diseases
- Surgery, to remove tumors or abnormal growths
- Chemotherapy and radiation therapy to halt the development of cancerous cells
- Blood transfusions
If the swelling of the lymph nodes is idiopathic, the vet may prescribe only some anti inflammatory drugs and monitor the evolution of the pet.
You should ask your vet if your pet has an infection and whether this is zoonotic or can be transmitted to humans, so that you can protect yourself.