In Home Lymph Node Exam:
An ounce of prevention is worth a pound of cure. Unfortunately, many diseases pets suffer from go undetected until progression is severe enough to produce harmful clinical signs -- and an equally scary hospital bill. In the interest of saving their pets (and their pocket books!), owners often ask me for simple measures they can take to identify early signs of disease. I give them two words: Lymph. Nodes. While there’s no way to completely avoid every health problem out there, frequent lymph node exams can tip owners off to subtle changes in their pets’ health. Not only do these exams offer owners the chance to detect inflammation, infection, and cancer, they also encourage owners to become more familiar with what’s normal for their animals.
So you’re probably wondering what lymph nodes are and how you can examine them. Most people are familiar with blood vessels and nerves, the highways of blood and synapses, respectively, that keep our bodies oxygenated and integrated. Less familiar are our lymphatic vessels, which transport certain types of immune cells. If lymphatic vessels are highways, lymph nodes are the cities they connect. These metropolises are masses of tissue that generate certain immune cells and serve as epicenters of immune cell activity. They are located throughout the body and named for their anatomical locations; peripheral lymph nodes may be felt externally, while internal lymph nodes are deep within the body. Peripheral lymph nodes occur in right/left pairs. Veterinarians assess these lymph nodes as part of their routine physical exams, however, owners can learn to do this at home on a more frequent basis. The lymph nodes that should be routinely felt on both sides of your pet are: the submandibular nodes, the prescapular nodes, the axial nodes, the inguinal nodes, and the popliteal nodes.
How you do it: If you aren’t fond of anatomy jargon, you aren’t alone! You can see a demonstration of each of these sites in the labeled images. To assess a lymph node, roll it between your thumb and index finger. For pets that are overweight you may have a tricky time locating the lymph node, as they are often surrounded by fat. Lymph nodes are kidney shaped and vary in size by species and breed, but generally small breed dogs have chickpea-sized nodes, medium breeds have pecan-sized nodes, and large breeds have brazil nut-sized nodes. Outside of these relative ranges, lymph nodes may be considered enlarged and you should have a veterinarian assess your pet.
What it means: Lymph nodes become enlarged when they generate more immune cells and increase the flow of lymphatic traffic. This is associated with swelling and heat at the site of the lymph node. It may be happening as a response to infection or, rarely, a cancerous change. Your veterinarian will take a sample from the lymph node using a needle and analyze it under a microscope. A special veterinarian known as a Veterinary Clinical Pathologist is often consulted to interpret the findings. Lymphoma, cancer of the lymph nodes, is the most common cancer found in dogs and often presents with enlarged nodes. Additionally, lymph nodes are often sites of early spread for other types of cancer. Early detection is very important! Providing your pet with diligent exams increases their chance of early disease detection and early treatment!
Dr. Matthew Schexnayder
Dr. Matthew Schexnayder