Lupus can cause skin rashes on many parts of the body, including the legs. Around 75% of people with lupus will experience skin symptoms. They are the first symptom in 25% of systemic lupus cases.
This statistic comes from DermNet NZ.
Lupus is a chronic autoimmune disease that can affect the body in many different ways. The
Some people also have cutaneous lupus erythematosus (CLE), which affects the skin and connective tissues. CLE can occur on its own, or alongside SLE.
Read on to learn more about lupus rashes on the legs, including the types, symptoms, and treatment.
There are several forms of skin disease that someone with CLE can develop.
Acute cutaneous lupus
Acute cutaneous lupus often appears on the face, but can affect other parts of the body, including the arms and legs. It can look similar to a sunburn, and the skin it affects is often swollen and itchy. This type of lupus rash usually occurs when someone with SLE is experiencing a symptom flare-up.
Subacute cutaneous lupus
Subacute cutaneous lupus usually presents in one of two ways. It can consist of inflamed, scaly patches of skin with clearly defined edges, or a rash with ring-patterned lesions.
This type of CLE often occurs in response to sun exposure. Neither of these rashes are likely to be itchy or to leave scars, but they may cause discoloration.
Chronic cutaneous lupus
Chronic cutaneous lupus, or discoid lupus, is the most common type of lupus skin disease. This type of lupus rash causes round or circular lesions. These lesions are usually scaly, thick and red in color. They do not typically cause discomfort or itching but may scar or cause discoloration.
While chronic cutaneous lupus most often appears on the face and scalp, it can occur anywhere on the body, including the legs.
People cannot confirm if a rash is lupus without speaking with a doctor. This is because many conditions can cause rashes on the legs that resemble CLE, including sunburn, eczema, and psoriasis. Only a health professional can determine the cause.
Some factors that may suggest, but not guarantee, that the cause is lupus include:
- having other lupus symptoms
- having a family history of lupus
- symptoms beginning after exposure to an environmental trigger, such as sunlight
The other symptoms of lupus
- joint pain or swelling
- swollen feet
- swollen eyes
- swollen ankles
- extreme fatigue
- muscle pain
- light sensitivity
- weight gain
- mouth sores
- memory problems
- hair loss
- chest pain
There are also a number of environmental factors that can trigger lupus. They include:
- exposure to UV light from sunlight or tanning beds
- serious injury
- cigarette smoke
- certain medications known to cause drug-induced lupus
To identify the cause of the rash on the legs, a doctor will ask about a person’s symptoms and when they began. They will also examine the legs.
If the doctor thinks lupus is a possibility, they may take a skin biopsy from the affected area to run tests on. They may also perform blood and urine tests.
When treating lupus rashes, doctors will put together a plan that takes into account the location, type, and severity of the rash. Depending on the situation, treatment may aim to:
- heal the rash
- relieve symptoms, such as itchiness
- prevent lasting damage, such as scarring or discoloration
- treat existing scarring
- prevent further flare-ups
This may involve a combination of:
Sunlight often triggers lupus rashes or makes them worse. A doctor may recommend protecting skin from the sun by:
- staying in the shade
- wearing light layers of clothing to protect bare skin, such as the legs
- wearing sunscreen of SPF 50 or above
- limiting outdoor activities during times when UV levels are highest
Treatments that target skin symptoms directly can usually reduce symptoms quickly, decreasing pain and inflammation. They may include:
- corticosteroid creams
- corticosteroid injections, which are used for thicker patches
- tacrolimus ointment, which may help if corticosteroids do not work or are unsuitable
Medications can reduce the impact of lupus overall, which in turn, can reduce skin symptoms. A doctor may prescribe:
- antimalarial medication, which can help clear lupus rashes over time
- immunosuppressants to prevent the immune system from attacking the body
- biologics, which can help slow or stop inflammation
- other medications, such as the antibiotic daspone or a retinoid, if a rash is not responding to other treatments
If these treatments do not work, or a person has thick or raised rashes and scarring, a doctor may also suggest laser therapy.
In addition to following a doctor’s medical plan for lupus rashes, people can also take steps to reduce the symptoms and prevent flare-ups at home and in the workplace. These include:
- replacing any lightbulbs that emit UV light, such as fluorescent or halogen bulbs
- installing UV shields on any lightbulbs a person cannot replace
- checking whether other medications a person takes can increase the skin’s sensitivity to the sun
- taking a vitamin D supplement, as avoiding sunlight means a person will get less of this nutrient
Some people with CLE also have Raynaud’s disease, which causes the fingers and toes to turn pale when they are cold. If this applies:
- take extra care to protect hands and feet from the cold by wearing gloves and socks
- keep the body warm by wearing layers, hats, and coats in cold weather
- avoid caffeine and nicotine, as these can make symptoms worse
There are also some things it is important for people with CLE to avoid, including:
- touching or scratching the rash
- using tanning beds
- exposure to secondhand smoke
It may be helpful to keep a symptom diary to track symptoms, medication side effects, and other things that may be triggering flares.
Some people may want to try
Anyone with a rash that they believe could be lupus should contact a doctor as soon as they can.
People who already have a lupus diagnosis and who develop a rash that is unusual, painful, or spreading should also speak with their doctor. This may indicate they need a change in their treatment plan to better manage symptoms.
An itchy rash on the legs could be a sign of lupus, particularly if it develops in response to environmental triggers that often affect people with lupus or if they have a family history of the disease.
The rash may look similar to sunburn, cause circular lesions, or cause scaly patches with distinct edges. However, many other conditions can cause these symptoms.
If a person does not already have a lupus diagnosis, they should discuss their concerns with a doctor. Treatments to reduce symptoms and prevent scarring are available.