Chilblains (pernio) is an uncommon, self-limited inflammatory condition of the acral skin caused by an abnormal vasospastic response to nonfreezing cold and damp exposure, presenting as erythematous to violaceous, edematous papules or plaques on the toes (82%), fingers (30%), ears, or face. [1-2] The condition predominantly affects young women and is typically benign, with conservative treatment (warming, drying) producing complete response in ~82% of patients. [1]
1. History
- Duration, onset, and temporal relationship to cold/damp exposure (lesions typically develop 12–24 hours after cold exposure) [3]
- Specific cold exposure details: temperature, duration (typically 1–5 hours at <16°C/60°F), wet vs. dry conditions [2]
- Symptom characterization: pruritus, burning, pain, tenderness — exacerbated by rapid rewarming [4]
- Seasonal pattern: onset in fall/winter, resolution in spring/summer suggests primary (idiopathic) pernio [3]
- Persistence beyond cold seasons raises concern for secondary pernio (underlying autoimmune or hematologic disease) [5]
- Prior episodes and recurrence pattern (acute vs. chronic pernio)
- Footwear and clothing habits (sandals in winter, wet socks, tight shoes) [3]
- Occupational cold exposure (construction, outdoor work) [6]
- Smoking history (vasoconstriction contributor)
- Important negatives: tissue freezing (frostbite), sharply demarcated triphasic color changes (Raynaud's), systemic symptoms (fever, weight loss, arthralgias)
2. Alarm Features
- Lesions persisting beyond cold seasons — suggests secondary pernio (SLE, connective tissue disease, hematologic malignancy) [5]
- Bullous or necrotic evolution of lesions [7]
- Associated joint pain/swelling, photosensitivity, oral ulcers, malar rash → lupus [5][8]
- Tissue necrosis or gangrene → consider frostbite, critical limb ischemia, thromboangiitis obliterans [9]
- Concurrent constitutional symptoms (fever, weight loss, lymphadenopathy) → hematologic malignancy (3% of pernio cases in one series) [1]
- Atypical demographics (older adults, males) with new-onset pernio warrant more aggressive workup for secondary causes [5]
3. Medications
- First-line pharmacologic treatment: Nifedipine 20–60 mg/day (off-label) — shown to reduce pain, facilitate healing, and prevent new lesions in an older RCT, though a more recent RCT found no superiority over placebo for chronic chilblains. Use warrants caution due to risk of hypotension and peripheral edema [4][10-11]
- Topical nitroglycerin — may improve peripheral perfusion [12]
- Other agents with limited evidence: pentoxifylline, tadalafil (may be superior to corticosteroids for primary pernio), fluoxetine (particularly for secondary pernio), hydroxychloroquine (for chilblain lupus) [8][12]
- Topical corticosteroids — may reduce inflammation acutely, though systemic corticosteroid efficacy is debated [8][12]
- Amitriptyline 50–100 mg at bedtime for neuropathic pain component; gabapentin as adjunct [13]
- Avoid rapid active rewarming — can worsen symptoms [4]
- Medications to consider as contributors: vasoconstrictors (nicotine, beta-blockers, ergotamines)
4. Diet
- No specific dietary triggers are well-established
- Adequate caloric intake is important — low BMI/thin body habitus is a risk factor, and anorexia nervosa predisposes to pernio in children and adolescents [3]
- Adequate hydration and warm fluids during cold exposure may help maintain peripheral perfusion
- Caffeine in excess may contribute to vasoconstriction
5. Review of Systems
- Dermatologic: photosensitivity, malar rash, discoid rash, oral/nasal ulcers (lupus features) [5]
- Musculoskeletal: arthralgias, joint swelling, morning stiffness (connective tissue disease) [8]
- Vascular: Raynaud's symptoms (triphasic color changes), acrocyanosis, digital ulcers
- Constitutional: fatigue, fever, weight loss (malignancy, autoimmune disease)
- Hematologic: easy bruising, bleeding, lymphadenopathy
- Renal: foamy urine, hematuria (lupus nephritis)
- Neurologic: numbness, paresthesias (neuropathy from more severe NFCI)
6. Collateral History and Family History
- Family history of autoimmune disease (SLE, Raynaud's, scleroderma, antiphospholipid syndrome) [14]
- Family history of cold sensitivity or chilblains
- Social context: housing conditions (inadequate heating), homelessness, occupational cold exposure
- History of eating disorders (anorexia nervosa) — particularly in adolescents [3]
- Recent viral illness (COVID-19 association with pernio-like lesions, "COVID toes") [15]
7. Risk Factors
- Female sex (79% of cases in the Mayo Clinic series) [1]
- Young age (mean age ~38 years; common in adolescents) [1][3]
- Low BMI / thin body habitus — associated with increased cutaneous vasoreactivity [3]
- Cold, damp climate — nonfreezing temperatures 0–16°C (32–60°F) [2]
- Inadequate protective clothing (sandals in winter, wet socks/shoes) [3]
- Smoking — contributes to vasoconstriction [1]
- Sedentary lifestyle / prolonged immobility in cold environments
- Underlying conditions: SLE, antiphospholipid syndrome, cryoproteins, Raynaud's disease, hematologic malignancy [1][14]
- COVID-19 infection (pandemic-associated pernio-like lesions) [15]
8. Differential Diagnosis
- Raynaud's phenomenon — sharply demarcated pallor → cyanosis → erythema, lasting hours (not days); no persistent papules [3]
- Frostbite — tissue freezing with necrosis; more severe, occurs at lower temperatures [3]
- Chilblain lupus — pernio-like lesions in the setting of SLE; persists beyond cold seasons, associated with photosensitivity and positive ANA/anti-dsDNA [5][9]
- Acrocyanosis — persistent symmetric cyanosis of hands/feet without papules
- Critical limb ischemia / peripheral arterial disease — absent pulses, claudication, tissue loss
- Thromboangiitis obliterans (Buerger's disease) — young male smokers, digital ischemia [9]
- COVID toes — pernio-like acral lesions temporally associated with SARS-CoV-2 infection, often in patients without cold exposure history [15]
- Trench foot (immersion foot) — more severe NFCI from prolonged (days) cold-wet exposure; involves deeper neurovascular damage [4]
- Erythema multiforme — target lesions, mucosal involvement
- Vasculitis (small vessel) — palpable purpura, systemic symptoms
The ARCTIC mnemonic has been proposed to aid in differential diagnosis of chilblain-like lesions: Acrocyanosis, Raynaud's, Critical limb ischemia, Thromboangiitis obliterans, Idiopathic chilblains, COVID toes. [9]
9. Past Medical History
- Prior episodes of chilblains (acute vs. chronic/recurrent pernio)
- Connective tissue disease (SLE, scleroderma, mixed connective tissue disease) [1][14]
- Antiphospholipid syndrome [14]
- Hematologic disorders (cryoglobulinemia, cold agglutinin disease, lymphoproliferative disorders — 3% in one series) [1]
- Raynaud's phenomenon
- Eating disorders (anorexia nervosa) [3]
- Recent COVID-19 infection [15]
- Peripheral vascular disease
- Smoking history
10. Physical Exam
- Skin: Erythematous to violaceous (purplish), edematous papules or plaques on acral surfaces — dorsal toes (most common), fingers, ears, nose, shins [2][12]
- Lesions may be single or multiple; may progress to vesicles, bullae, or superficial ulceration in severe cases [7]
- Tenderness to palpation of lesions
- Upon rewarming: skin becomes red, hot, swollen with itching/burning [2]
- Vital signs: generally normal; check for hypothermia if concurrent cold exposure
- Vascular exam: peripheral pulses (should be intact — absent pulses suggest PAD or frostbite); capillary refill
- Assess for signs of connective tissue disease: malar rash, discoid lesions, oral ulcers, joint synovitis, sclerodactyly, nail fold capillary changes
- Body habitus: note low BMI [3]
11. Lab Studies
Most cases of primary (idiopathic) chilblains require no laboratory workup if the presentation is classic and self-limited. [1] Labs are indicated when secondary pernio is suspected:
- CBC with differential — screen for cytopenias (lupus), lymphoproliferative disorders [1]
- ANA — screening for SLE/connective tissue disease; positive in ~22.5% of pandemic chilblains cohorts, usually low titer [5][7]
- Anti-dsDNA, anti-Smith antibodies — if ANA positive, to evaluate for SLE [16]
- Antiphospholipid antibodies (anticardiolipin, anti-β2-glycoprotein I, lupus anticoagulant) [14]
- Complement levels (C3, C4) — low in active lupus
- Cryoglobulins, cryofibrinogen, cold agglutinins — cold agglutinins were positive in 55% of tested pernio patients; cryoglobulins were negative in all tested patients in the Mayo series. Routine cryoglobulin testing may not be necessary [1][5]
- ESR, CRP — nonspecific inflammatory markers
- Serum protein electrophoresis — if hematologic malignancy suspected
- D-dimer — may be elevated (60% in one cohort), though clinical significance is uncertain [7]
- Rheumatoid factor, immunoglobulins — hypergammaglobulinemia and RF positivity may distinguish secondary from idiopathic pernio [5]
12. Imaging
- Imaging is generally not indicated for typical chilblains
- If diagnostic uncertainty exists regarding vascular compromise:
- Arterial Doppler ultrasound — to rule out PAD or critical limb ischemia
- MRI of digits — may show phalangeal bone marrow edema in some cases of secondary chilblains with inflammatory arthritis [8]
- Nailfold capillaroscopy — can help differentiate primary Raynaud's from secondary (scleroderma pattern)
13. Special Tests
- Skin biopsy — not routinely needed but confirmatory in atypical cases. Histology shows: superficial and deep perivascular lymphocytic infiltrate, dermal edema, necrotic keratinocytes, perieccrine inflammation, and vascular changes (endothelialitis, microthromboses) [17-18]
- Direct immunofluorescence — may show granular C3/IgM deposition in vessel walls; helps differentiate from lupus (lupus band test) [7]
- Nailfold capillaroscopy — to evaluate for underlying connective tissue disease
- Punch biopsy if concern for vasculitis, lupus, or malignancy
14. ECG
- Not routinely indicated for isolated chilblains
- Consider ECG if concurrent hypothermia is suspected (Osborn/J waves, bradycardia, prolonged QT)
- If nifedipine is being prescribed, baseline assessment of blood pressure is more relevant than ECG
15. Assessment
Chilblains is a clinical diagnosis based on characteristic acral erythrocyanotic papules/plaques in the setting of cold-damp exposure. The condition is classified as:
- Primary (idiopathic): Most common; self-limited; seasonal; no underlying systemic disease [1]
- Secondary: Associated with SLE, antiphospholipid syndrome, connective tissue disease, hematologic malignancy, or viral infection (COVID-19) [1][14-15]
- Acute pernio: Develops 12–24 hours post-exposure; self-limited over 1–3 weeks [3]
- Chronic pernio: Recurrent with repeated cold exposure; lesions persist [3]
Key distinguishing features of secondary pernio: persistence beyond cold seasons, older age, male sex, photosensitivity, hypergammaglobulinemia, and positive rheumatoid factor. [5] Conservative treatment alone achieves complete response in the majority of patients. [1]
16. Treatment Plan
Initial management (all patients)
- Gentle passive rewarming — avoid rapid active rewarming [4]
- Clean, dry, and elevate the affected limb [3]
- Protect from further cold/damp exposure with warm socks, gloves, insulated footwear
- Smoking cessation [1]
- NSAIDs (ibuprofen) or acetaminophen for mild pain
Pharmacologic therapy (moderate-severe or recurrent cases)
- Nifedipine 20–60 mg/day (extended-release preferred) — traditional first-line pharmacotherapy, though evidence is mixed (one older RCT positive, one newer RCT negative). Monitor for hypotension and peripheral edema [4][10-11]
- Topical corticosteroids — for symptomatic relief of inflammation
- Amitriptyline 50–100 mg at bedtime — for neuropathic pain [13]
- Gabapentin — adjunct for refractory neuropathic pain [13]
Secondary pernio
- Treat the underlying condition (e.g., hydroxychloroquine for chilblain lupus, immunosuppression for inflammatory arthritis) [8][12]
- Fluoxetine and antimalarials show promise for secondary pernio [12]
17. Disposition
- Discharge is appropriate for the vast majority of chilblains cases — this is an outpatient condition [1][3]
- Admission criteria: Essentially none for isolated chilblains. Consider admission only if:
- Concurrent significant hypothermia or frostbite requiring monitoring
- Severe secondary pernio with systemic disease flare (e.g., active SLE with organ involvement)
- Tissue necrosis or superinfection requiring IV antibiotics or surgical consultation
- Specialist consultation triggers:
- Rheumatology referral if ANA positive (≥1:80) or features of connective tissue disease [16]
- Dermatology referral for atypical lesions, biopsy consideration, or refractory cases
- Hematology referral if concern for lymphoproliferative disorder [1]
18. Follow Up / Return Precautions
- Follow-up in 2–3 weeks with primary care or dermatology to assess resolution [6]
- Acute pernio typically resolves within 1–3 weeks with conservative measures [2-3]
- Return precautions — seek immediate reassessment for:
- Worsening pain, expanding necrosis, or new bullae
- Signs of secondary infection (increasing erythema, warmth, purulent drainage, fever)
- New systemic symptoms (joint pain, rash in sun-exposed areas, fatigue, weight loss)
- Lesions persisting beyond the cold season
- Patient counseling:
- Prevention is the best therapy — keep skin warm and dry; wear insulated, moisture-wicking socks and gloves; avoid prolonged cold-wet exposure [3-4]
- Avoid tight footwear that restricts circulation
- Smoking cessation is critical [1]
- Maintain adequate caloric intake and healthy body weight [3]
- Prognosis for properly treated primary pernio is excellent [3]
References
1. Clinical Characteristics, Etiologic Associations, Laboratory Findings, Treatment, and Proposal of Diagnostic Criteria of Pernio (Chilblains) in a Series of 104 Patients at Mayo Clinic, 2000 to 2011. — Cappel JA, Wetter DA. Mayo Clinic Proceedings. 2014.
2. American College of Sports Medicine Position Stand: Prevention of Cold Injuries During Exercise. — Castellani JW, Young AJ, Ducharme MB, et al. Medicine and Science in Sports and Exercise. 2006.
3. Pernio in Pediatrics. — Simon TD, Soep JB, Hollister JR. Pediatrics. 2005.
4. Heat and Cold Illness in Travelers. — Howard D. Backer and Luanne Freer CDC Yellow Book. 2025.
5. Epidemiological Patterns of Perniosis, and Its Association With Systemic Disorder. — Takci Z, Vahaboglu G, Eksioglu H. Clinical and Experimental Dermatology. 2012.
6. Perniosis a Case Report With Literature Review. — Baker JS, Miranpuri S. Journal of the American Podiatric Medical Association. 2016.
7. Clinical, Laboratory, and Interferon-Alpha Response Characteristics of Patients With Chilblain-like Lesions During the COVID-19 Pandemic. — Hubiche T, Cardot-Leccia N, Le Duff F, et al. JAMA Dermatology. 2021.
8. Novel Association of Chilblains With Inflammatory Arthritis- Series of Three Cases and Review of Literature. — Joshi N, Ullah S, Shah A, Dubey S. Rheumatology International. 2025.
9. A Review of COVID-19 Chilblains-Like Lesions and Their Differential Diagnosis. — Sachdeva M, Mufti A, Maliyar K, et al. Advances in Skin & Wound Care. 2021.
10. The Treatment of Chilblains With Nifedipine: The Results of a Pilot Study, a Double-Blind Placebo-Controlled Randomized Study and a Long-Term Open Trial. — Rustin MH, Newton JA, Smith NP, Dowd PM. The British Journal of Dermatology. 1989.
11. Nifedipine vs Placebo for Treatment of Chronic Chilblains: A Randomized Controlled Trial. — Souwer IH, Bor JH, Smits P, Lagro-Janssen AL. Annals of Family Medicine. 2016.
12. An Evidence-Based Review of Perniosis (Chilblains): Therapeutic Strategies and Integration With Raynaud's Syndrome Management. — Sharifzadeh A, Smith GP. International Journal of Dermatology. 2025.
13. Prevention and Treatment of Nonfreezing Cold Injuries and Warm Water Immersion Tissue Injuries: A Supplement to the Wilderness Medical Society Clinical Practice Guidelines. — Zafren K, Hollis S, Weiss EA, et al. Wilderness & Environmental Medicine. 2023.
14. Epidemiologic Analysis of Chilblains Cohorts Before and During the COVID-19 Pandemic. — McCleskey PE, Zimmerman B, Lieberman A, et al. JAMA Dermatology. 2021.
15. Pernio (Chilblains), SARS-CoV-2, and COVID Toes Unified Through Cutaneous and Systemic Mechanisms. — Cappel MA, Cappel JA, Wetter DA. Mayo Clinic Proceedings. 2021.
16. Systemic Lupus Erythematosus: A Review. — Siegel CH, Sammaritano LR. The Journal of the American Medical Association. 2024.
17. Chilblain-Like Acral Lesions During the COVID-19 Pandemic ("COVID Toes"): Histologic, Immunofluorescence, and Immunohistochemical Study of 17 Cases. — Kanitakis J, Lesort C, Danset M, Jullien D. Journal of the American Academy of Dermatology. 2020.
18. Histopathologic Features of Chilblainlike Lesions Developing in the Setting of the Coronavirus Disease 2019 (COVID-19) Pandemic. — Sohier P, Matar S, Meritet JF, et al. Archives of Pathology & Laboratory Medicine. 2021.