Rashes and swollen lymph nodes are two symptoms that can occur in a variety of conditions. Some causes include viral and bacterial infections, such as scarlet fever, shingles, or Lyme disease. Other causes can include a reaction to certain medications and cancer.
Rashes can look very different depending on their cause. For example, they can appear as blisters, blotches, or welts, and they can be dry, itchy, flushed, or scaly.
According to the National Cancer Institute, lymph nodes are part of the body’s lymphatic system, which is part of the immune system. These nodes carry white blood cells, as well as waste products and fluid, away from cells and tissues.
Lymph nodes are located in the neck, under the arms, the chest, the abdomen, and the groin.
When a person has a specific condition or infection, the lymph nodes can become swollen. Lymph nodes that are closer to the surface of the skin may become visible, and a person may be able to feel them with their fingers. Swollen lymph nodes can be painful and tender.
This article will discuss some of the most common causes of rashes and swollen lymph nodes. It will also look at some potential treatment options and when to seek medical help.
The following infections can cause rashes and swollen lymph nodes:
Chickenpox is a contagious condition that occurs due to the varicella-zoster virus. Although it commonly affects children, it can affect anyone at any age.
The classic symptom of chickenpox is a rash. This rash presents as small, itchy blisters that eventually scab over. The rash will often start on the back, face, and chest, then spread to other regions of the body.
Swollen lymph nodes may also be present in a person with chickenpox.
Other symptoms of chickenpox can include:
- a high temperature
- appetite loss
- feeling unwell
- aches and pains
These symptoms tend to last for 5–7 days.
Chickenpox is a self-limiting condition, meaning that it will typically resolve by itself over time.
A healthcare professional will advise a person with chickenpox to remain isolated from other people until the blisters have scabbed over.
People can also wear gloves to make sure that they do not scratch the blisters.
They should also drink fluids regularly to prevent dehydration.
Shingles is a condition that occurs due to the varicella-zoster virus, which is the same virus that causes chickenpox.
The National Institute on Aging note that approximately half of all shingles cases affect adults aged 60 years or older.
Shingles occurs when this virus, which continues to live in the nerve cells, becomes reactivated.
A person with shingles will develop a rash, which will then turn into fluid filled blisters.
Some people may also have swollen lymph nodes that feel tender. Shingles typically affects one side of the body.
Other symptoms of shingles may include:
- burning or tingling pain, which is often the first symptom
People should seek treatment for shingles as soon as they notice symptoms. This can lower the risk of developing post-herpetic neuralgia, reduce the risk of the virus spreading to others, and shorten the course of the infection.
Treatment for shingles includes taking prescription antiviral medication, wearing loose-fitting clothing, and keeping the rash dry and clean to prevent infection.
Applying a cold washcloth to the rash can also help with the burning pain sensation.
Group A strep
Group A Streptococcus (Group A strep) is a bacterium that can cause a variety of illnesses that can result in rashes and swollen lymph nodes. The following are some of those illnesses:
Scarlet fever can cause a sore throat, a rash, and a fever.
The Centers for Disease Control and Prevention (CDC) note that anyone can get scarlet fever. However, it is more common in those aged 5–15 years.
A person may also notice swollen lymph nodes on the side of their neck.
According to one 2020 article, around 2 days after infection, a non-itchy rash starts to develop. The rash begins as many small spots that go from pink to red. They also feel rough.
This rash can then spread to cover the neck, torso, hands, and feet within a few days. After a few weeks, these spots should disappear.
Cellulitis is a skin infection that causes swelling and pain in the affected area of skin. The rash can also be red, purple, or black. The CDC note that the skin may look pitted and that blisters may appear.
A person may also experience fever and chills.
Although it can appear anywhere on the body, cellulitis commonly affects the legs and feet.
Antibiotics can treat scarlet fever, tonsilitis, and cellulitis.
A doctor may also recommend taking over-the-counter (OTC) pain medications, such as ibuprofen, to treat the symptoms of sore throat and fever.
Measles is a viral infection. According to one 2020 article, public health officials declared the elimination of measles in 2020. However, outbreaks continue to occur because not everyone has received the vaccine.
In measles, a rash appears. The rash begins on the face and can spread to the other regions of the body, including the torso, abdomen, and arms. It typically fades after a week.
Swollen lymph nodes may also occur in the back of the neck.
Other symptoms of measles can include:
- a cough
- small white spots on the inside of the mouth
- red, sore eyes that may be sensitive to light
- a runny nose
The treatment options for measles aim to prevent infection and relieve the symptoms.
They include taking OTC pain medications and drinking fluids to prevent dehydration.
People with measles should isolate themselves during the initial stages of the infection, such as when the rash appears.
A distinct symptom of Lyme disease is a circular red rash with a central red area.
Some people with Lyme disease may also experience swollen lymph nodes and:
- aches and pains
- joint pain
- night sweats
A person with Lyme disease can take antibiotics such as amoxicillin or doxycycline. The severity of Lyme disease will determine the course of antibiotics.
The following infections can also cause rashes and swollen lymph nodes:
An autoimmune condition occurs when the immune system attacks the body.
The National Institute of Arthritis and Musculoskeletal and Skin Diseases note that healthcare professionals are unsure what causes autoimmune conditions.
However, people are often genetically predisposed to autoimmunity, which something, such as a virus or other infection, can then trigger.
One notable autoimmune condition that can cause a butterfly rash and swollen lymph nodes is systemic lupus erythematosus, or lupus. A butterfly rash affects the face and appears on the cheeks and bridge of the nose.
Treatment aims to help a person manage the symptoms and prevent flares. A person can try complementary therapies alongside medication.
Lymphoma and leukemia are two types of cancer that can cause rashes and swollen lymph nodes.
The American Cancer Society note that the main difference between the two is that in leukemia, the cancer cells are typically in the blood and bone marrow. With lymphoma, however, the cancer cells are in the lymph nodes and other tissues.
Lymphoma is a cancer that begins in the white blood cells, or lymphocytes.
There are two types of lymphoma: Hodgkin lymphoma and non-Hodgkin lymphoma.
Leukemia is an umbrella term that refers to cancers that affect the blood cells.
Leukemia can be acute, which means that it develops quickly, or chronic, which means that it develops slowly.
The type of leukemia a person has will also depend on whether the cancer originated in the myeloid cells or the lymphoid cells.
Although the symptoms of different types of leukemia will vary, some people will experience a rash and swollen lymph nodes on the sides of the neck, under the arms, or in the groin area. This can occur in acute lymphocytic leukemia.
In cancer, swollen lymph nodes may be painless, whereas infections and inflammation tend to cause swollen lymph nodes that are tender to the touch.
Treatment for leukemia and lymphoma will depend on the type that has developed. Options may include:
- radiation therapy
- bone marrow transplant
Sometimes, rashes and swollen lymph nodes can result from an allergic reaction to a drug. This is known as drug-induced hypersensitivity syndrome.
For example, in a 2018 study in the journal Case Reports in Hematology, a person developed a rash and swollen lymph nodes after taking minocycline, which is an antibiotic.
It is important to identify allergic reactions to drugs early, as they can sometimes present similarly to other conditions.
Although treatment will depend on the type of drug that caused the reaction, healthcare professionals will typically recommend that a person stops taking the drug to prevent the symptoms from worsening.
In the study above, a healthcare professional also prescribed corticosteroids to help treat the hypersensitivity reaction.
A healthcare professional will normally examine the person experiencing these symptoms and take their medical history.
They may also feel that it is necessary to run tests to determine the cause, and they may refer the person to a specialist.
In suspected cases of leukemia, a blood test can see whether or not the number of white blood cells present is abnormal. Other tests include a biopsy, wherein a healthcare professional may remove cells from the body to examine them under a microscope.
Although some of the causes of rashes and swollen lymph nodes are self-limiting, a person should still seek the advice of a doctor if they experience these symptoms.
They should also seek help if the swollen lymph nodes are especially painful or if they feel hard and remain swollen for a long period of time.
A variety of conditions can cause a rash and swollen lymph nodes.
Although these symptoms are typically due to an infection, such as shingles or scarlet fever, other causes, such as leukemia, may be more serious.
If a person is worried about their symptoms, they should contact their doctor as soon as possible.
This list of possible causes is not exhaustive. To accurately determine the cause of these symptoms, a healthcare professional needs to make a diagnosis.