Chilblains: Symptoms, Types, Causes and Treatment

Chilblains, sometimes known as perniosis, are an often misunderstood condition that brings discomfort to many people, especially during cold and damp seasons. Although usually benign and self-limiting, chilblains can cause significant pain and distress. In recent years, increased attention has been given to this condition due to its association with broader autoimmune diseases and even as a potential skin manifestation during the COVID-19 pandemic. In this comprehensive article, we explore chilblains in depth—covering their symptoms, types, causes, and available treatments—to help patients, caregivers, and healthcare professionals better understand and manage this condition.

Symptoms of Chilblains

Chilblains can be unsettling for those who experience them, often appearing suddenly after exposure to cold, damp weather. Recognizing the symptoms is the first step to ensuring timely and effective care.

Symptom	Description	Common Location	Sources
Red or purple lesions	Painful, inflamed patches on skin	Fingers, toes, heels	1,2,3
Swelling	Localized, sometimes with itching	Acral areas (extremities)	1,2,3
Pain & burning	Soreness, sometimes with stinging	Affected skin	1,3
Ulceration (rare)	Cracking or open sores	Severe or chronic cases	8
Pruritus	Itchy sensation	Often fingers/toes	2,3

Table 1: Key Symptoms

Common Clinical Manifestations

Chilblains are primarily characterized by the sudden appearance of red or purple papular lesions—small, raised patches—on acral areas such as the fingers, toes, heels, and occasionally the nose and ears. These lesions are usually painful, swollen, and may be accompanied by intense itching or burning sensations. The affected skin can feel sore to the touch, and some individuals report a stinging feeling, especially as the area warms up after being cold 1,2,3.

Severity and Progression

While most chilblains are mild, in chronic or severe cases, the lesions can blister, crack, or even ulcerate. This is more common in familial or autoimmune-associated types, where lesions may progress to necrotic ulcerations if not managed appropriately 8.

Triggers and Onset

Symptoms typically appear within hours after exposure to cold and damp conditions but can also be delayed. The onset is often rapid, and the lesions resolve within a few weeks, especially when the affected areas are kept warm and dry. Recurrences are common, particularly during winter months or with repeated cold exposure 3.

Types of Chilblains

Chilblains are not a one-size-fits-all condition. They can occur on their own or as part of an underlying disease, and recognizing the type is crucial for tailored management.

Type	Description	Distinguishing Features	Sources
Idiopathic	Occurs in otherwise healthy individuals	No systemic disease	1,3
Secondary	Associated with autoimmune/systemic disease	May have other systemic signs	2,4,8
Chilblain lupus	Chronic, familial, or autoimmune-related	Severe, sometimes mutilating	4,6,8
"COVID toes"	Chilblain-like lesions during COVID-19	Young patients, pandemic link	5,7,9

Table 2: Types of Chilblains

Idiopathic Chilblains

Idiopathic chilblains are the most common form, typically affecting otherwise healthy people. They arise without any detectable underlying disease and are most frequent in women and individuals with low body mass index 1,3.

Secondary Chilblains

Secondary chilblains develop as a manifestation of other diseases, most commonly connective tissue and autoimmune disorders such as systemic lupus erythematosus (SLE) and antiphospholipid syndrome. Unlike idiopathic cases, affected individuals may also present with other systemic symptoms, warranting further laboratory investigations 2,4,8.

Chilblain Lupus Erythematosus

This chronic form is associated with lupus and other genetic mutations (e.g., TREX1, SAMHD1, STING). Chilblain lupus tends to be familial, presents early in life, and often leads to more severe symptoms, including ulceration, necrosis, and systemic involvement. It is linked to type I interferon pathway activation 4,6,8.

COVID-19 Associated Chilblains ("COVID Toes")

During the COVID-19 pandemic, an increased incidence of chilblain-like lesions—termed "COVID toes"—was observed, especially in children and young adults. Their exact relationship with SARS-CoV-2 remains controversial. Some believe these are direct viral manifestations, while others suggest they result from lifestyle changes (e.g., more time at home barefoot) or robust immune responses 5,7,9.

Causes of Chilblains

Understanding what causes chilblains is vital for prevention and management. While the classic trigger is environmental, many underlying factors can contribute.

Cause	Mechanism or Risk Factor	Notes/Examples	Sources
Cold, damp exposure	Vasospasm in superficial blood vessels	Most common trigger	3
Autoimmune disease	Immune-mediated vessel inflammation	SLE, antiphospholipid	2,4,8
Genetic mutations	Familial forms, often with IFN activation	TREX1, STING mutations	6,8,12
COVID-19	Possible viral or immune response	"COVID toes"	5,9
Low BMI/Female sex	Increased susceptibility	Higher risk group	1
Smoking	Vasoconstriction exacerbates risk	Modifiable factor	3

Table 3: Causes and Risk Factors

Environmental Triggers

The most prevalent cause of chilblains is exposure to cold, non-freezing, and damp conditions. This triggers abnormal vasospasm in the superficial blood vessels of the skin, leading to localized inflammation. The condition is particularly common in climates with cool, wet winters 3.

Autoimmune and Systemic Diseases

Chilblains can also be a cutaneous sign of underlying autoimmune diseases such as lupus erythematosus and antiphospholipid syndrome. In these cases, immune-mediated inflammation of the small blood vessels plays a central role 2,4,8. Laboratory testing for autoantibodies may be warranted in atypical, recurrent, or severe cases, especially if the patient has other systemic symptoms 2.

Genetic and Familial Causes

Certain familial forms of chilblains are due to genetic mutations, most notably in the TREX1 and STING genes. These mutations result in inappropriate activation of the type I interferon pathway, leading to chronic inflammation and systemic involvement. Familial chilblain lupus often presents in childhood and tends to be more severe, with systemic features like arthritis or lymphopenia 6,8,12.

COVID-19 and Other Factors

The emergence of "COVID toes" has highlighted a possible link between viral infections, immune responses, and chilblain-like lesions. However, the evidence is still inconclusive, and the increase in cases during the pandemic may also be due to behavioral changes during lockdowns 5,9.

Other risk factors include low body mass index, female sex, and smoking, all of which increase susceptibility, possibly by affecting blood flow or the body's response to cold 1,3.

Treatment of Chilblains

Managing chilblains effectively requires a combination of prevention, symptomatic care, and, in rare cases, targeted therapies for underlying causes.

Treatment	Description/Mechanism	Evidence/Effectiveness	Sources
Warming measures	Avoiding cold, keeping extremities warm	First-line, most effective	3
Smoking cessation	Reduces vasoconstriction risk	Recommended lifestyle mod	3
Nifedipine	Calcium channel blocker, vasodilator	Mixed evidence	10,11
Topical corticosteroids	Reduces inflammation	No proven benefit	3,13
Immunomodulators	JAK inhibitors, hydroxychloroquine	Used in familial/autoimmune	6,12
Other therapies	Pentoxifylline, topical nitroglycerin	Limited data, some benefit	3

Table 4: Treatment Approaches

General and Preventive Measures

The cornerstone of chilblain management is preventative: keeping the affected areas warm and dry, avoiding rapid temperature changes, and wearing appropriate clothing during cold weather. Smoking cessation is strongly encouraged, as tobacco use can exacerbate vascular constriction 3.

Pharmacological Treatments

The use of medications is generally reserved for persistent, recurrent, or severe cases.

Nifedipine

Nifedipine, a calcium channel blocker and vasodilator, has been studied for chilblains. Early studies reported that nifedipine reduced the duration and severity of lesions and prevented new episodes 10. However, more recent randomized controlled trials have failed to confirm significant benefits over placebo, and side effects like edema and hypotension were noted 11. Therefore, routine use is no longer universally recommended.

Topical Corticosteroids

Topical steroids such as betamethasone are sometimes used to reduce inflammation and itching. However, clinical trials have shown no significant benefit compared to placebo in chronic chilblains, suggesting these should not be used routinely without further supporting evidence 3,13.

Immunomodulatory and Other Therapies

In secondary chilblains or familial chilblain lupus, treatment is often targeted at the underlying disease. Options may include immunomodulators like hydroxychloroquine or JAK inhibitors (e.g., tofacitinib, baricitinib) in cases with interferon pathway activation 6,12. These are typically reserved for severe, chronic, or systemic cases and require specialist supervision.

Other treatments such as pentoxifylline and topical nitroglycerin have shown some benefit in small studies or anecdotal reports but lack robust evidence 3. Acupuncture has also been reported to provide symptom relief in some cases 3.

When to Seek Further Evaluation

Laboratory investigations and biopsy should be considered in patients with chronic, recurrent, or severe lesions, or when systemic symptoms or signs of autoimmune disease are present. This helps rule out underlying causes and guides more specific therapy 2,3.

Conclusion

Chilblains are a fascinating yet often distressing skin condition that bridges the worlds of dermatology, rheumatology, and even infectious disease. Understanding their symptoms, types, causes, and treatments is crucial for effective management and for identifying cases where further investigation is warranted.

Key takeaways:

• Chilblains manifest as painful, red or purple lesions, primarily on the fingers and toes, often following cold and damp exposure 1,2,3.
• They can be idiopathic, secondary to autoimmune disease, familial/genetic, or associated with COVID-19 ("COVID toes") 3,4,5,6,7,8,9.
• Underlying risk factors include cold/damp weather, autoimmune conditions, genetic mutations, female sex, low BMI, and smoking 1,2,3,4,6,8.
• The mainstay of treatment is preventive: keeping extremities warm and avoiding cold exposure 3.
• Pharmacological interventions like nifedipine and corticosteroids have shown mixed or limited benefit, while immunomodulatory agents are reserved for severe or autoimmune-associated cases 3,10,11,13.
• Persistent, severe, or systemic cases warrant further investigation to rule out underlying autoimmune or genetic conditions 2,4,6,8.

By recognizing the varied presentations and underlying causes of chilblains, individuals and healthcare professionals can better navigate this condition and ensure timely, effective care.