What this means
A dog's lymph nodes can be felt in several places: under the jaw, in front of the shoulders, in the armpits, in the groin and behind the knees. Healthy nodes are usually small and hard to feel, while enlarged ones feel like firm or rubbery lumps under the skin, often the size of a bean or an egg. Owners usually find them while stroking their dog.
It matters to note whether one node is enlarged or several, whether on both sides of the body, and whether your dog is sore or lethargic. A single enlarged node close to the mouth, teeth or a wound often points to local inflammation. Several enlarged nodes in different places can point to a more general process that needs investigating.
A lump under the skin can be mistaken for a lymph node and the other way round, so only a vet can tell them apart. It is often looked into by taking a small sample of cells. Write down where you found the lump, how big it is and whether it is growing, and do not press or massage it hard.
Possible causes
These are things that can cause this sign. It is not a diagnosis, and they are not equally likely for your dog.
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Local infection or inflammation
A node enlarges near a wound, the teeth or a skin inflammation, because the body's fighting cells pass through it. Usually one or two nodes closest to the problem are enlarged.
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Lymphoma
A cancer of lymph tissue, in which the nodes become large and firm but usually painless. A dog may feel well for a while, so the first sign is sometimes only lumps.
About the condition: Lymphoma (lymphosarcoma) -
Spread of other cancers
Some growths can spread to nearby lymph nodes. An enlarged node can be the first sign that there is a growth somewhere else.
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Immune system disorders
In disorders of the immune system the nodes can enlarge without an infection. A fever, lethargy or sore joints are often noticed.
What else to watch for
These observations help your vet build the picture faster. Note down what you saw and when.
- Where the enlarged nodes are and how many there are
- Whether they are on both sides of the body or in one place only
- Whether they are growing, or lethargy, fever or a poor appetite came with them
- Whether your dog is losing weight, drinking more or coughing
- Whether there is a wound, mouth problem or skin inflammation nearby
- Whether the nodes are painful to touch
When to book a routine visit
Book a visit within a few days if you find enlarged lymph nodes, especially if there are several, they are growing or your dog is lethargic. If your dog struggles to breathe or swallow, go straight away.
Related conditions
Conditions whose entries mention this sign. The list is somewhere to read on, not a way to reach a diagnosis.
- Lymphoma (lymphosarcoma) Cancer Lymphoma is a malignant tumour that arises from lymphocytes, the white blood cells that form part of the immune system. It affects the lymph nodes, but it can also involve the spleen, liver, intestines, skin or other organs. Because lymphocytes travel throughout the body, the disease can affect the whole system, so any changes you notice should be shown to a vet promptly.
- Cancer Cancer Cancer is not one disease but a whole group of different malignant tumours that can appear in almost any organ or tissue. They can grow slowly or quickly and spread to other parts of the body, so the earlier a change is noticed, the more options a vet has. Only a vet can tell whether a lump or other change is malignant.
- Autoimmune disorders Blood and immunity This is an umbrella term for conditions in which the immune system, instead of defending the body against germs, starts attacking the dog's own tissues. The skin, blood cells, joints or internal organs can be affected, so these diseases can look very different from one another. What the condition is and what caused it is for the vet to determine.
- Lyme disease Infections Lyme disease is a bacterial infection passed to a dog by an attached tick. In Lithuania its bacteria are spread by the castor bean tick, which lives in woods, parks and long grass. Some infected dogs show no signs at all, while others develop painful joints weeks or months later; whether this disease is behind a dog's illness is for a vet to establish.
Body systems: Cancer Blood and immunity Infections