When you’re sick, swollen lymph nodes can often be a worrisome symptom. You might experience them in your neck, armpits, or groin if you are experiencing a viral infection, such as the common cold, and they can feel quite sore until they begin to swell down.
Swollen lymph nodes usually should not be a sign to worry. When they begin to swell, it is merely a sign that your body is doing its best to fight off this infection. The lymph nodes are part of the lymphatic system, which is the immune system’s way of regulating bodily fluids, removing cellular waste, and most importantly: fighting off any infections.
“They reflect the body’s response to acute inflammation,” says Stanley Rockson, M.D., director of the Stanford Center for Lymphatic and Venous Disorders and professor of lymphatic research and medicine at Stanford Health care.
The lymphatic system is composed of many vessels that carry immune cells throughout the body, according to the Cleveland Clinic. The nodes themselves are filled with many infection and disease fighting cells. The fluid carrying the immune cells that travels throughout the body are scanning for any bacterial invaders or viruses. When detected, the nodes increase the number of disease-fighting cells, which results in swelling so that the infection can be fought off. Dr. Rockson notes that swelling is completely normal and is only temporary, as these areas will calm down over time.
When your body is fighting off an infection, you may notice that these lymph nodes found in your neck, groin, or armpit are swollen and enlarged. You might not see any difference, but there may be a small bump in any one of these areas. They can feel like little “rubbery nodules” that can be the size of a pea, cherry, or even a plum in certain circumstances. They may also vary in texture, ranging from tender to soft to firm.
So, when exactly do you get swollen lymph nodes? Here are some of the most common causes.
Just received a vaccine
Getting a vaccine quite recently means your body is building up immunity to a certain kind of disease. The annual flu shot or the most recent COVID-19 vaccine can spark an immune response, as it is only introducing the body to part of the infection. “The vaccine creates antibodies in the lymph nodes. In order for the response to occur, those cells have to expand in number, which causes the nodes to enlarge. That’s all part of the normal bodily response [to a vaccine],” explains Dr. Rockson. You might experience some swollenness around your arm, where you might have received the vaccine or your neck, which is the most common area for swollen lymph nodes.
Common infection
As mentioned before, catching a viral infection could result in swollen lymph nodes. Any upper respiratory infections, ear infections, strep throat, tonsillitis, pink eye, tooth infections, measles, mononucleosis, or even a skin infection can result in some flu-like symptoms, and of course, swollen lymph nodes. Most infections will resolve on their own with proper rest and with some medication, if necessary. With certain infections like pink eye, you might need antibiotics to help clear it up.
…Or a less common infection
There are a few rarer infections that can also result in swollen lymph nodes. Tuberculosis, some STI’s (i.e. HIV or syphilis) or toxoplasmosis (a parasitic infection) can result in swelling in multiple areas. With a viral infection, you may experience two nodes swelling in the same place, whereas with a less common infection, you may experience one swollen lymph node by your jaw and perhaps one in your armpit or groin, according to the Cleveland Clinic. As with more common, viral infections, you should always consult with your doctor as they can provide diagnostic tests and treatment depending on your symptoms.
Autoimmune disorder/disease.
An autoimmune disorder is any disease that causes the immune system to attack healthy organs, tissues or cells. There are more than 80 recognized autoimmune illnesses, according to the National Institutes of Health, including psoriasis, celiac disease, type 1 diabetes, lupus, and rheumatoid arthritis (RA). An overactive and “misfiring” immune system can cause swollen lymph nodes at times (usually with lupus or RA). If you are concerned, however, you should talk to your doctor who can look at any joint pain or swelling, and can give you a proper diagnosis, if necessary.
Cancer
While it is very rare, says the American Cancer Society, swollen lymph nodes could possibly be a sign of cancer. In reality, doctors estimate that less than 1% of those who have the symptom have cancer. According to Dr. Rockson, “In the case of cancer, the lymph nodes are trapping cancer cells to prevent their spread through the body. The immune system responds to cancer like it’s a foreign invader, but though the lymph nodes can contain the cancer, they can’t resolve it. Lymphoma typically leads to swollen lymph nodes, but any cancer can lead to it, adds Dr. Rockson. With lymphoma, cancer can usually start in the lymph nodes and spread to other lymph node parts in the body.
While swollen lymph nodes are usually a good sign that your body is fighting off infections, if you notice that the lymph nodes persist for more than two-to-four weeks, it is best to consult your doctor. You may also consult with them if these nodes become more painful, increase in size, accompanied by night sweats, or are more firm to the touch.
According to Dr. Rockson, “it’s never wrong to get something evaluated when you’re concerned, Lymph node enlargement is part of normal biology. But when it’s excessive, when it’s persistent, when it’s continuing to get worse over time, that’s when it’s a good idea to get it evaluated.”