Lymphadenitis in Dogs

Enlarged lymph nodes are generally a sign of infection. In the case of lymphadenitis, the cause is typically of a benign nature, though malignant forms are documented as well. Abnormalities and swelling of the lymph node can result in symptoms that will alert you to the fact that there is an ongoing disease present. However, it can happen that your veterinarian will find enlarged glands that you weren’t aware of during a routine examination.

Lymphadenitis is the enlargement of one or more lymph nodes in the body. The lymph nodes, or glands, increase in size in response to the influx of inflammatory cells. 

The symptoms that you may see in your dog (in addition to these) will most likely be related to the primary disease that is causing the gland enlargement. If your dog has swollen glands, he may exhibit signs, or appear asymptomatic even if he is in pain.

• Fever
• Loss of appetite
• Weight loss
• Weakness
• Distended abdomen
• Coughing
• Difficulty swallowing (dysphagia)
• Excessive thirst (polydipsia)
• Excessive urination (polyuria)
• Vomiting
• Diarrhea
• Soft, tender nodes upon palpation

Types 

Lymphadenitis is classified depending on the extent of range in the body.

Solitary

• A single lymph node is enlarged

Regional

• A specific anatomical area is affected and the lymph nodes are usually interconnected

General

• More than one area of the body is altered

It should be noted that severe lymphadenitis can extend into adjacent tissues, and can be classified as superficial or deep.

There are a large number of causes for lymph node inflammation, a few of which are listed here.

Infectious

Bacterial

• Brucella canis
• Streptococci
• Septicemia

Rickettsial (frequently transmitted by mites, ticks)

• Salmon poisoning
• Ehrlichiosis

Fungal

• Aspergillosis
• Histoplasmosis

Parasitic

• Toxoplasmosis
• Babesiosis

Viral

• Canine viral enteritides
• Infectious canine hepatitis

Non Infectious

• Drug reactions, immune mediated disorders like rheumatoid arthritis

Infiltrative (Neoplastic)

• Leukemia
• Multiple Myeloma
• Mast Cell Tumor
• Lymphoma

Nonneoplastic

• Eosinophilic granuloma complex
• Mast cell infiltration

Part of the diagnosis of the lymph node inflammation will involve checking carefully for underlying disease processes. When you bring your furry family member to the clinic, be ready to relay as much information as possible in regards to the behavior of your dog in recent days.Your veterinary team will ask questions in order to learn more about the health status of your beloved pet.

• Has your dog been eating well?
• Does he have trouble swallowing?
• Does he appear to be in pain?
• Do you think he has lost weight?
• Has his behavior changed (energy level, enthusiasm for regular activities)?

Your veterinarian will order a complete blood count and serum biochemistry, to look for specific markers that may point to illness or infection (hypercalcemia and hyperglobulinemia are common with lymph node inflammation). A test called polymerase chain reaction (PCR) will analyze and identify tissues. 

She may want to perform radiographs of the chest, neck, and abdomen, especially if she has been able to locate any glands that are swollen. An ultrasound can prove to be a good diagnostic tool as well since it can give a good view of organs that may be affected.

A fine needle aspirate, or needle core, partial, or excisional biopsy may be done for further investigation into the inflammatory origin.

The therapy for lymphadenitis will depend on the cause. Antibiotics, antifungal medications, and anti-inflammatories will be prescribed as required. Surgery, chemotherapy and radiation in the case of neoplastic inflammation will be considered, with regular follow up appointments needed to verify if the cancer is being eradicated.

Because the root of the problem can vary extensively, your veterinarian will discuss with you the various options or therapies required to best get your pet back to a normal state of health.

The recovery of lymphadenitis will depend completely on the response that your dog’s system has to the therapy. The age of your pet, their current health status, and the underlying condition will all influence prognosis.

Always complete any medicinal prescriptions that your veterinarian has prescribed, even if your pet appears to be getting better. Keep all follow up appointments as well, because many types of lymph node inflammation need careful monitoring to assure that they are being thoroughly dealt with.

Lymphadenitis can be expensive to treat. To avoid high vet care expenses, secure pet health insurance today. The sooner you insure your pet, the more protection you’ll have from unexpected vet costs.