Introduction

Have you observed that your fingers become red, itchy or appear swollen after being exposed to cold temperatures? This is a very common reaction that many people experience in cold, damp weather, known as chilblains. In some cases, a sore that appears similar may indicate a more serious condition referred to as chilblain lupus.

Although these conditions are similar, they have different causes. Chilblain is caused when cold temperatures lead to the narrowing of small blood vessels in the extremities, such as the fingers and toes. This constriction makes it difficult for blood to flow easily in response to the cold conditions. However, chilblain lupus is an autoimmune condition that can indicate an underlying problem, such as systemic lupus erythematosus, also known as lupus. 

It is essential to understand the distinction between the two conditions, as chilblain lupus may necessitate medical intervention, whereas chilblains typically resolve without treatment. This article will explain how to differentiate between them, outline the causes of each condition, and indicate when it is necessary to seek medical attention. 

What are chilblains? 

Chilblains (also known as pernio) are characterised by small itchy swellings on the skin that can be red and sometimes purple, which develop due to cold conditions. This painful reaction affects the body’s extremities, such as toes, fingers, heels, face, ears and nose.

How do they develop?

The small blood vessel under the skin constricts (temporary vasoconstriction) to conserve heat when the skin is exposed to cold temperatures. Under normal physiological conditions, exposure to cold causes the small blood vessels in the hands and feet to constrict, reducing blood flow to these areas.¹ This response helps the body conserve heat but also leads to a rapid drop in temperature in the extremities. In people who are susceptible to chilblains, the blood vessels constrict for too long or reopen suddenly, leading to fluid leakage, inflammation, and irritation. 

Symptoms of chilblain appear within 12 to 24 hours after exposure to cold. In more serious cases, small blisters or ulcerations can form. Most chilblains subside on their own within 1 to 3 weeks, especially when the person avoids further cold exposure.²

What are the risk factors for chilbains??

Environmental

• People who live in cold, damp climates or work outdoors are more likely to develop chilblains. Frequent or prolonged exposure to chilly, humid conditions increases the risk because temperature changes repeatedly stress the skin’s blood vessels.^3,4

Low BMI and smoking

Having a low body mass index, or smoking can both reduce blood flow to the hands and feet. Poor circulation makes it harder for the body to regulate temperature in the extremities, which can contribute to the development of chilblains.³

What is chilblain lupus?

Chilblain lupus is an uncommon complication associated with cutaneous lupus erythematosus (CLE), a type of lupus that affects the skin. It leads to painful sores that are red or purplish, typically appearing on the fingers or feet, while the nose and ears are less frequently affected. The condition is typically seen in people already diagnosed with CLE; however, it can also appear on its own without an earlier lupus diagnosis. Chilblain lupus occurs more often in women than men and may develop as a primary condition or as a secondary manifestation of other autoimmune diseases, such as CLE.⁵

Causes 

The exact mechanisms that cause chilblain lupus are not fully known; however, research has shown that exposure to cold plays a key role. In chilblain lupus, cold temperatures damage blood vessels in the skin (vasoconstriction or microvascular), similar to chilblains, resulting in poor circulation and clotting of small vessels, which subsequently leads to inflammation. People with underlying conditions, such as lupus and autoimmune factors, may have immune system changes that cause it to attack the skin’s tissues, especially in areas already affected by cold exposure. In rare familial cases, scientists have found mutations in genes such as TREX1, which are believed to disrupt proper DNA repair and immune regulation, making tissues more susceptible to damage and immune attack.⁶

Symptoms of chilblain lupus

The symptoms of chilblain lupus initially resemble those of simple chilblain but tend to last longer and have more severe effects. 

Typical symptoms include:

• Painful red, purple, or dark patches on the fingers, toes, heels, nose, or ears, which may feel itchy, burning, or tender to the touch
• Swelling of the skin in the affected areas 
• Blistering and sores, resulting in the skin surface breaking, forming sores and ulcers
• Patches of skin losing colour (depigmentation)

Key Difference from Regular Chilblains 

Chilblain and chilblain lupus may appear similar on the skin, but they are distinct conditions. The main differences are the underlying causes and the duration of each condition.

In ordinary chilblain, the reaction is triggered by exposure to cold and damp conditions, which lead to temporary inflammation of small blood vessels in the skin. Chilblains are uncomfortable, but usually harmless and typically heal on their own with the right management, whereas chilblain lupus involves an autoimmune condition. In this case, the body's immune system attacks healthy skin tissues, especially in areas affected by cold or poor circulation, often making the condition more persistent and likely to leave scars.⁷

Another important distinction is that chilblain lupus is associated with systemic lupus erythematosus, which is an autoimmune condition that affects the skin, joints, and internal organs. Individuals with chilblain lupus typically require ongoing medical follow-up and, in certain instances, medication to manage inflammation.³

Management and treatment 

Managing chilblains 

In most cases, chilblains will improve on their own within a few weeks. There are simple steps that can be completed to ease symptoms and prevent recurrence. It is important to keep the body warm and avoid sudden temperature changes. Small steps, like wearing gloves and socks, keeping rooms warm and staying dry in damp weather, can help reduce flare-ups. 

Gentle skincare also makes a difference. Using a mild, fragrance-free moisturiser helps protect the skin’s barrier, while avoiding tight footwear improves circulation. If the skin becomes very itchy or inflamed, doctors may recommend a mild steroid cream to reduce irritation or an antiseptic cream to prevent infection. Most people recover without complications once they stay warm and protect their skin.

Managing chilblain lupus

Chilblain lupus, however, requires medical intervention and ongoing management because it is linked to autoimmune activity rather than just cold exposure. Treatment aims to reduce inflammation and prevent flare-ups. Doctors may prescribe corticosteroids for mild cases of the skin or oral corticosteroids and immunosuppressive medicines if the condition is more persistent. In many patients, hydroxychloroquine, a medication commonly used in lupus, helps control symptoms and prevent recurrence.⁷

Lifestyle changes, such as avoiding smoking and ensuring that hands and feet remain warm, also play a crucial role in maintaining healthy blood flow.

When to seek medical help?

Most cases of chilblains heal without needing medical treatment, but you should see a doctor if the sores don’t heal within a few weeks, keep coming back each winter, or become painful, swollen, or ulcerated. Persistent or severe lesions may suggest chilblain lupus or another underlying condition that needs professional care.

You should also seek medical advice if you notice other symptoms of lupus, such as unexplained fatigue, joint pain, skin rashes, or fever. A doctor can carry out blood tests or a skin biopsy to check for lupus-related changes and recommend suitable treatment.

Summary 

Although chilblains and chilblain lupus can look alike on the skin, they are very different in how they develop and how they are managed. Chilblains are a short-term reaction to cold and damp weather that causes temporary irritation of small blood vessels in the skin. They usually heal on their own with warmth, gentle skincare, and protection from the cold.

Chilblain lupus, on the other hand, is an autoimmune condition in which the body’s immune system mistakenly attacks healthy skin tissue. This makes the condition last longer, often recur, and sometimes lead to scarring. Because it can be linked to systemic lupus erythematosus, it requires medical follow-up and, in some cases, specific medication to control inflammation and prevent complications.

Recognising the difference between these two conditions is important for proper care. While ordinary chilblains are usually harmless and self-limiting, chilblain lupus needs medical attention to manage symptoms and monitor for signs of lupus elsewhere in the body. If sores don’t heal, keep returning, or are accompanied by joint pain, tiredness, or fever, seeking medical advice early can help prevent scarring and detect lupus before it becomes more serious.