What Is the Lupus Butterfly Rash?

A malar rash, commonly known as a butterfly rash, is one of the classic signs of lupus. The immune system mistakenly targets and attacks healthy tissues in people with lupus. A butterfly rash is the result of an immune response to sunlight exposure.

Butterfly rashes are also common with rosacea, a skin condition that causes facial redness. One of the main differences between a butterfly rash with lupus and rosacea is the characteristics. For example, lupus usually causes flat, red rashes, while rosacea causes raised, red rashes with acne-like lesions.

Butterfly rashes are common with lupus, affecting about 46% to 65% of people with the autoimmune disease. Read on to learn about the butterfly rash and how to prevent flares.

What Is Butterfly (Malar) Rash?

Lupus that affects your skin is called cutaneous lupus erythematosus (CLE). The butterfly rash develops across the cheeks and nose, bypassing the folds of the skin around the mouth. That type of rash is known as acute cutaneous lupus (acute skin lupus).

You can usually identify a butterfly rash by its color and signature shape. A butterfly rash might look a lot like sunburn: The rash typically ranges from a very light to a deep shade of red, depending on the person.

Skin problems like the butterfly rash are common among those with lupus. Other skin changes that might occur with lupus include petechiae (small red spots due to under-skin bleeding) and vasculitis (damaged skin blood vessels). Some people with lupus develop calcinosis, or calcium deposits underneath the skin.

Lupus vs. Rosacea Rash

The butterfly rash is also common with rosacea, an inflammatory skin condition that causes facial redness. Butterfly rashes might present differently in people with lupus and those with rosacea. 

Here are some the differences between lupus and rosacea butterfly rashes:

What Causes the Rash?

Photosensitivity, or sun allergy, is a reaction to ultraviolet (UV) light exposure and causes a butterfly rash. People with lupus are usually sensitive to UV light from the sun and artificial sources like indoor lighting.

At the cellular level, your immune system might cause a butterfly rash to appear on your skin. Your immune cells essentially create skin lesions in response to UV light exposure. Those lesions stimulate other immune cells, causing flares.

The reason for the butterfly rash's shape is not entirely clear. Some evidence suggests that butterfly rashes sometimes only appear on skin that consistently gets sunlight.

Other Butterfly Rash Causes

Several health conditions, in addition to lupus and rosacea, can cause a butterfly rash, such as:

• Cellulitis: A skin infection that does not usually have systemic symptoms
• Dermatomyositis: An inflammatory skin condition that causes hyperpigmentation (uneven skin tone)
• Erysipelas: A skin infection with systemic symptoms like chills and fever
• Pellagra: A systemic illness that occurs due to a lack of cellular niacin (a B vitamin)

Diagnosis of Lupus

It might be difficult and take a long time to diagnose lupus since there's no one way to tell whether you have it. Instead, a healthcare provider might use several tests to diagnose lupus. They will likely start by asking about your personal and family health history and doing a physical exam.

A healthcare provider might use several blood tests to diagnose lupus, including:

• Antinuclear antibodies (ANA): Most people with lupus have positive ANA results. In contrast, not everyone with a positive ANA has lupus. A healthcare provider might test for other antibodies to confirm lupus.
• Complete blood count (CBC): People with lupus might have low platelet, red blood cell, and white blood cell counts.
• Metabolic panel: This checks your kidney function.

Other tests include kidney and skin biopsies. A healthcare provider will take a sample of your kidney tissue or skin to look at under a microscope.

Lupus Rash Treatment

There are treatments available to help get rid of a butterfly rash.   Treatment effectiveness can vary from person to person, depending on the type of lupus.

Lupus treatments that help get rid of butterfly rashes include:

• Antimalarial medications: These typically treat malaria, a parasitic infection, but can also help get rid of skin rashes. Antimalarial medications treat signs of inflammation, such as fatigue and joint pain.
• Corticosteroids: These include oral and topical steroids like creams and gels, which you apply directly to your skin. A dermatologist might use an injectable steroid to treat thick skin patches.
• Immunosuppressants: These drugs reduce your body’s immune response. Immunosuppressants sometimes treat severe lupus cases.

How To Prevent Flares

You can do a few things to prevent butterfly rash flares if you have lupus, such as:

• Avoid sunlight during peak hours: Limit outdoor activities to the early morning or late evening. Cloud cover and shade help shield you from UV rays, but they will not offer complete protection.
• Do not touch any rashes on your skin: This will keep butterfly rashes from worsening.
• Consider switching to incandescent or LED light bulbs: You can also try UV light filters or shields if replacing light bulbs is not an option.
• Cover up outdoors: Wear long sleeves, pants, and wide-brimmed hats. Try choosing fabrics that offer UV protection, like polyester and nylon.
• Use a broad-spectrum, waterproof sunscreen: Choose one with an SPF of 50 or more. The higher the SPF, the more protection you have from the two main types of UV light from the sun (UVA and UVB).

A Quick Review 

Lupus, an autoimmune disease, is one of the primary causes of butterfly rash. Other health conditions like cellulitis or rosacea might cause the rash. A butterfly rash is typically the result of an immune system response to UV light exposure.

Treatments like antimalarial medications and steroids help treat a butterfly rash. You might prevent flares by avoiding peak sunlight hours and protecting yourself while outdoors.