This symptom can be worrisome, especially if you’re not certain what is causing it. The axillary lymphadenopathy differential diagnosis also may be difficult because of all the possible causes.
This article will discuss possible causes and symptoms to look out for. It will help you to know when to see a healthcare provider and to understand more about diagnostic tests and axillary lymphadenopathy treatment.
Symptoms of Axillary Lymphadenopathy
Axillary lymphadenopathy is characterized by swelling and inflammation of one or more of the 20 to 40 axillary lymph nodes in each armpit. The swelling may involve one armpit, which is known as unilateral, or both armpits, known as bilateral.
Unilateral swelling is often (but not always) a symptom of an infection or disease on that side of the body. Bilateral swelling tends to point to systemic illness—that is, an illness affecting the entire body.
Swollen axillary lymph nodes can range in size from a small pea to a large grape. They can feel spongy or hard like a marble. They may also be accompanied by additional symptoms, including:
Warmth of the lymph nodes and surrounding skin Redness of the lymph nodes and surrounding skin Lymph nodes that are painful or tender Lymphedema (swelling of the affected arm) Fever and chills Fatigue Malaise Joint or muscle pain Night sweats Unexplained weight loss Splenomegaly (swollen spleen)
Causes of Swollen Lymph Nodes in the Armpit
Lymph nodes are part of the lymphatic system, which plays a central role in immune function, fluid balance, and absorption of fats and fat-soluble nutrients. Other parts of the lymphatic system include lymph fluid, lymph vessels, the spleen, tonsils, and the thymus gland.
Lymphadenopathy is a sign that the lymphatic system has triggered an immune response to defend against an invader—specifically, an infection or illness. The immune response works like this:
First, the invader enters the lymph vessels and lymph fluid. Lymph fluid flows to the lymph nodes for inspection by the immune system. Once the invader is detected, inflammatory proteins (cytokines) and defensive white blood cells (lymphocytes) are released. Their job is to isolate and neutralize the invader within the lymph node. As a result, inflammation and fluid build-up in the lymph node leads to swelling. We recognize this swelling as lymphadenopathy.
There are many possible causes of axillary lymphadenopathy, including:
Local infection, such as streptococcal and staphylococcal skin infections, or other infections that are localized to the arm, hand, chest, or shoulder Short-term inflammation, such as after receiving a shoulder or arm tattoo Vaccinations for measles, smallpox, tuberculosis, COVID-19, and anthrax, which are linked to unilateral lymphadenopathy on the same side as the injected arm Strep throat, which can affect the axillary lymph nodes as well as the cervical lymph nodes Cat-scratch fever, resulting from a cat scratch on an arm or hand Sporotrichosis, a rare, localized fungal infection that results in swelling of the nearby lymph nodes Hidradenitis suppurativa, a painful skin condition of uncertain cause that affects sweat glands Tularemia, a rare infectious disease that typically attacks the skin, eyes, lymph nodes, and lungs HIV, because axillary and cervical lymph nodes are often affected in the early stages of infection Autoimmune lymphoproliferative syndrome, a syndrome characterized by swollen lymph nodes in the armpit, neck, or groin Lymphoma, a cancer of the lymph nodes and lymphatic tissue that causes swollen lymph nodes, usually in the armpit, neck, or groin Regional cutaneous tuberculosis, a form of tuberculosis characterized by scaly and crusting skin lesions Breast cancer, because axillary lymphadenopathy typically occurs with locally advanced breast cancer or inflammatory breast cancer
Diagnosis
Axillary lymphadenopathy can usually be identified with a physical exam. Your healthcare provider may discover swollen lymph nodes during a routine checkup even if you have no symptoms.
To begin to determine if armpit pain or other symptoms could be related to cancer, infection, or another cause, they will consider several factors, including:
Size of the lymph nodesNumber of swollen lymph nodesPain or tendernessLocation (unilateral vs. bilateral)Consistency (whether the nodes are hard or spongy)Matting (whether the nodes are conjoined or individual)Mobility (whether the nodes are movable or not)
Together, these clues may point to certain diagnoses and help exclude others.
Lab Tests and Procedures
In addition to a physical exam, your healthcare provider will review your medical history and symptoms. They’ll ask about recent vaccinations, unexplained weight loss, recent sexual exposures, or abnormal skin lesions.
This information will help them determine which tests to include in the workup, such as:
C-reactive protein levels: high levels in the blood indicate generalized inflammationErythrocyte sedimentation rate (ESR): a blood test that reveals inflammation in the bodyWhite blood cell count: an elevated lymphocyte count in the blood may suggest infectionInfection-specific tests: used to identify HIV, tuberculosis, or streptococcusImmunologic blood tests: used to help detect autoimmune diseaseSkin biopsy: a procedure that may be done if skin lesions are presentDiagnostic mammogram or breast ultrasound: used to detect breast cancerImaging studies: X-ray, ultrasound, computed tomography (CT), or magnetic resonance imaging (MRI)Lymph node biopsy: used to determine if an infection, autoimmune disorder, or cancer is involved
Differential Diagnosis
Lumps and masses in the armpit don’t always indicate lymphadenopathy. Some may be benign or malignant growths not related to the lymphatic system, such as:
Lipomas: benign tumors composed of mature fat cells Epidermal inclusion cysts: benign cysts usually found on the skin Fibroadenomas: benign, painless breast lumps that can extend to the armpit Schwannomas: benign tumors of nerve sheaths Malignant neuroendocrine tumors: a cancer involving cells of the nervous and endocrine systems that occasionally affects the armpit
These conditions usually can be differentiated with imaging studies and other procedures, such as fine-needle aspiration.
Axillary Lymphadenopathy Treatment
There is no specific axillary lymphadenopathy treatment. Instead, it is resolved by treating the underlying condition.
Symptoms of lymphadenopathy can respond to certain home or over-the-counter (OTC) remedies:
A cold compress may relieve inflammation. Nonsteroidal anti-inflammatory drugs (NSAIDs) like Aleve (naproxen) and Advil (ibuprofen) can relieve pain and inflammation. If an infection is involved, rest is vital.
In cases of advanced breast cancer, the axillary lymph nodes are removed as part of a radical or modified mastectomy.
Summary
When your body detects a foreign invader—be it an illness, an infection, or even a vaccine—your lymphatic system will trigger an immune response to fend off the perceived threat. As lymphocytes and cytokines attack the invader, your lymph nodes will swell, resulting in lymphadenopathy.
Sometimes, axillary lymphadenopathy can be a sign of a serious illness, such as HIV, lymphoma, or breast cancer. You should make an appointment with your healthcare provider if you are concerned, or if:
Your lymph nodes are swollen for no apparent reasonThe swelling does not resolve within two to four weeksThe swelling continues to worsenYour lymph nodes feel hard, irregular in shape, or fixed in placeYou have a fever, night sweats, or unexplained weight loss
A Word From Verywell
A swollen lymph node is not an uncommon condition. But it should never be ignored if it is persistent, severe, or unexplained. When seeing a healthcare provider, provide as much information as possible about what you had been doing or experiencing before the lymphadenopathy started. The more your healthcare provider knows, the sooner a diagnosis can be made.
There was an error. Please try again.
