Lymph nodes are small glands in various places in the body, including the head, neck, armpits, and groin.
Lymph nodes are a vital part of the body’s immune system. They trap viruses, bacteria, and other invading microbes. Then, certain white blood cells inside the lymph nodes destroy these invaders.
The lymph nodes in the groin are also called femoral or inguinal lymph nodes.
Most of the time, people cannot see or feel their lymph nodes. However, if the nodes swell, they may be tender and painful. When this occurs, it is usually a sign that the body is fighting an illness or inflammation.
Swollen lymph nodes in the groin may indicate an infection or inflammation near those particular lymph nodes.
In this article, learn about the possible causes of swollen lymph nodes in the groin, as well as when to see a doctor.
The American Academy of Dermatology say that the lower leg or foot is a common site for cellulitis in adults. If the infection occurs in this area, it may cause swelling of the lymph nodes in the groin.
Any break in the skin can cause cellulitis, which may produce the following symptoms near the site of the injury:
Cellulitis can become severe without treatment. People who have symptoms of cellulitis should seek medical attention.
A person can acquire a sexually transmitted infection (STI) if they have sexual contact with someone else with an infection. STIs, such as gonorrhea, syphilis, genital herpes, and HIV, can cause swollen lymph nodes in the groin.
Symptoms of STIs can vary widely but may include:
- pain, swelling, or itching in the genital area
- unusual discharge from the penis or vagina
- blisters, sores, or warts on the genitals
- intermenstrual bleeding
- fever, headaches, or fatigue
Many STIs have no symptoms at all, so people should get regular testing.
Jock itch is a fungal infection that often affects the groin, buttocks, and inner thighs. Along with lymph node swelling in the groin, it can cause severe itching and a ring shaped rash.
Jock itch is a symptom of a ringworm infection. Over-the-counter antifungal creams or powders that treat ringworm often clear it up.
If the rash does not go away with antifungal treatment, it is best to see a doctor.
An overgrowth of a fungus called Candida can cause an infection in the vagina or on the penis.
As with other fungal infections in the genital area, this can affect the lymph nodes in the groin. Other symptoms of a yeast infection include:
- burning during urination
- itching and irritated skin
- foul-smelling lumpy white discharge
- redness and bumps that may contain pus
Vaginal or penile yeast infections often respond well to antifungal medicines. People should see a doctor for a diagnosis before treating a yeast infection at home if it is the first time they have experienced one.
Cat scratch disease, also called cat scratch fever, is a bacterial infection. A person can get it if an infected cat scratches them and breaks the skin.
Cat scratch disease can also develop if an infected cat licks an open wound on a person’s body.
If this infection occurs on the feet or legs, it may cause swollen lymph nodes in the groin.
Other symptoms of cat scratch disease include:
- swelling, pain, or redness near the scratch or wound
- round, raised sores containing pus
- lack of appetite
Infected cats generally show no signs of illness. Cat scratch disease often goes away over time in people who have a healthy immune system.
It can lead to serious complications in some people, but this is rare.
Bacteria can cause urinary tract infections (UTIs) and bladder infections, leading the lymph nodes in that area to swell. Some other symptoms include:
- frequent urge to urinate
- painful urination
- burning or stinging feeling in the area
- passing little urine
These infections may sometimes require antibiotics. UTIs can lead to more severe infections if a person does not receive treatment.
If a person gets a cut or blister on their foot, bacteria may enter through the skin and cause an infection. This infection can, in turn, cause swelling in the lymph nodes in the groin.
People who have diabetes or neuropathy may be particularly at risk of getting a foot injury without being aware of it. They should check their feet daily for signs of an injury and avoid going barefoot outdoors.
Athlete’s foot, also known as tinea pedis, is a fungal infection that affects the feet.
People may get the infection from walking barefoot in moist public areas, such as swimming pools and locker rooms.
As the body is fighting the fungus, it may cause swollen lymph nodes in the groin. However, athlete’s foot is not a common cause of this symptom, so a person with swollen lymph nodes in the groin should consider other causes before assuming that athlete’s foot is responsible.
Common symptoms of athlete’s foot include:
- itching and burning between the toes
- scaling or peeling of the skin on the feet, especially between the toes
- swelling of the feet or toes
- cracked skin or blisters on the feet or toes
In rare cases, swollen lymph nodes in the groin can be a sign of certain types of cancer that affect the area.
The types of cancer may include:
These cancers may have very few symptoms at first. If a person notices swollen lymph nodes in their groin without an obvious cause, they should see a doctor for an evaluation.
When an infection, inflammation, injury, or other illness affects the body, lymph nodes may swell as they gather the harmful cells and filter them.
A person may be able to feel swollen lymph nodes by gently pressing on the area. They may be tender or painful.
A swollen lymph node in one area can signal that there is inflammation or an infection in that specific area of the body. Doctors refer to this as localized lymphadenopathy.
For instance, swollen lymph nodes in the neck could be a symptom of a cold or the flu. Swollen lymph nodes in the groin are usually a sign that there is an infection or inflammation in the genitals or lower body, such as the legs or possibly the feet.
When more than one area of lymph nodes swell, this is called generalized lymphadenopathy. It may mean that the person has a body-wide infection, impaired drainage, or an immune system disorder.
People should see a doctor if they have persistently swollen lymph nodes that do not lessen over the course of a few days, or if the lymph nodes are painful or causing discomfort.
Treatment for swollen lymph nodes depends on the cause. For instance, cellulitis or skin infections usually require antibiotics.
Jock itch or athlete’s foot may clear up with antifungal medicines. If there is no clear cause of an infection, a doctor may run tests for other conditions.
After treating the underlying cause, the swollen lymph nodes will go back to their normal size.
Swollen lymph nodes are not a disease. They are a sign that the body is fighting off an infection.
In most cases, it is best to see a doctor to determine the cause of swollen lymph nodes in the groin. The doctor can recommend the necessary treatment or order further testing to help them confirm a diagnosis.