What causes you to have a red nose or butterfly rash?

A red nose or butterfly-shaped rash (malar rash) across the cheeks and bridge of the nose are both common symptoms of lupus, an autoimmune disease that causes the body's immune system to attack its own tissues and organs. When lupus affects the skin, it's medically referred to as cutaneous lupus or, specifically for these facial symptoms, discoid lupus erythematosus (DLE).

Here's a breakdown of why lupus can cause these specific skin manifestations:

1. Red Nose (Lupus Pernio):

- Lupus pernio is a specific type of skin lesion associated with lupus. It presents as a reddish-purple discoloration of the nose, and sometimes the cheeks, ears, and fingers.

- The exact mechanism causing lupus pernio is not fully understood, but it involves inflammation of the small blood vessels in the affected areas, leading to redness and swelling.

- The affected areas may feel cold to the touch, causing a sensation similar to chilblains, which are swellings that develop in response to cold temperatures.

2. Butterfly Rash (Malar Rash):

- The butterfly rash, also known as the malar rash, is a characteristic skin manifestation of lupus. It is a symmetrical rash that appears across the cheeks and bridge of the nose in a butterfly-shaped pattern.

- This rash is caused by inflammation of the skin that occurs when the immune system mistakenly attacks the healthy tissue in those areas. The inflammation leads to dilation and leakage of the small blood vessels, resulting in the reddish appearance.

- The malar rash may worsen with sun exposure, heat, stress, or other triggers.

It's important to note that while these skin symptoms can occur in lupus, the precise cause of lupus itself is complex and multifactorial. Various genetic and environmental factors are believed to contribute to the development of the disease. Therefore, a diagnosis of lupus is based on a combination of symptoms, blood tests, and other diagnostic criteria.

If you have a persistent red nose or butterfly-shaped rash, it's advisable to consult a healthcare professional for an accurate diagnosis and appropriate management.