- Chilblains (pernio) is a benign condition that occurs in cold, damp environments and presents with symmetric, distal, transient red-to-purple lesions on the extremities.
- Treatment is centered on keeping the patient warm and avoiding exposure to cold, damp environments.
- Cases which persist or occur in association with systemic symptoms may be an indication of a multisystem disease such as chilblain lupus erythematosus, a rare variant of systemic lupus
Chilblains, also termed pernio, is a benign inflammatory condition of the distal skin which occurs in cold, damp environments. The skin findings of chilblains typically occur in subfreezing, moist climes during the late fall and winter and are due to persistent exposure to temperatures presumed to transient vascular changes in the periphery.
In the United States, most patients present with skin findings between December and January, though the disease is overall more common in England and northern Europe. Chilblains is rare in regions of extreme cold, as most people require warm houses with central heating, and warm layered clothing during outdoor exposure. The condition is more common in women than men, with about a 2:1 ratio. Most reports are in white patients who are young to middle-aged. Patients with low BMI seem to be at increased risk.
Lesions of chilblains typically occur 1-5 hours after prolonged exposure to cool, damp air, and develop as single or multiple erythematous-to-purple macules, papules, plaques, or nodules; diffuse lesions over the digits may be seen. Lesions are more common on the dorsal aspects of the digits, and may be pruritic, painful (burning or tingling), and are often tender to palpation. Erosions, ulcers, and blisters may occur but are rare. Involvement of the feet is most common, followed by the hands. When the lesions appear they are often bilateral and affect cool extremities, particularly the digits. The nose, ear, lateral thighs, and buttocks may be involved.
The pathophysiology is uncertain, though it is believed that patients with pernio have a disruption of neurovascular responses to skin temperature change. Vessels in the skin have multiple protective physiologic responses to dilate and constrict variably based on the need to conserve heat or to ensure tissue perfusion and prevent ischemia; in patients with pernio some have postulated that there is either prolonged vasoconstriction leading to mild tissue hypoperfusion and localized inflammation in response to tissue injury. Vasospasm, hyperviscosity, or (in some patients) autoimmunity may alternatively be responsible for the disease.
The main treatment is keeping warm. Maintaining core body temperature warmth is essential, but layering warm garments over the affected or disease-prone extremities is important as well. Individual lesions will often resolve with warming, though it often requires days to a few weeks to completely return to normal. Intensely inflamed or extensive lesions may take weeks to months to completely resolve. Lesions that take many months to resolve or fail to resolve should prompt consideration of alternate diagnoses, particularly chilblains lupus erythematosus. Pharmacological interventions are often not required, although there are reports of nifedepine and other calcium channel blockers being helpful in treating or preventing recurrent perniosis.
The terminology of this condition may be a source of confusion; given the rare potential systemic disease associations reported in patients exhibiting idiopathic chilblains (pernio) lesions, it is worth a brief discussion. Lupus pernio refers to classic violaceous nodules and plaques on the central face in patients with sarcoidosis; pernio and chilblains refer to the idiopathic cold-induced skin lesions described herein. Chilblain lupus erythematosus is a rare subtype of systemic lupus which presents with distal digital lesions similar (or in some cases identical to) those seen in idiopathic chilblains.
Patients with chilblains may rarely have associated diseases, and in severe, atypical, persistent, or recurrent cases, a systemic workup may be indicated. Idiopathic chilblains (pernio) is rarely associated with joint inflammation, and the presence of arthritis should prompt consideration for multisystem disease. Patients with chilblains lupus erythematosus often exhibit cutaneous pernio lesions which fail to respond or respond only minimally over months. Patients with other features of systemic lupus who present with distal digital lesions consistent with pernio warrant a systemic evaluation. While not required for the diagnosis, patients with idiopathic pernio may undergo skin biopsy, and should features of interface dermatitis and histologic findings suggestive of lupus be noted, those patients should undergo an evaluation for possible chilblain lupus erythematosus.
The presence of angulated, retiform purpura, or nonblanching sharply angled distal lesions, may prompt a consideration of a systemic thromboembolic disease, including cryoglobulinemia or anti-phospholipid antibody syndrome. Lesions of pernio have been reported in patients with chronic myelomonocytic leukemia, and patients with extensive or atypical cutaneous lesions, cellular atypia on histology, or suggestive systemic symptoms warrant an evaluation. Raynaud phenomenon involves acute vaso-occlusive/vasospasm leading to the entire affected digit(s) turning purple, red, and white, as opposed to the more localized lesions of pernio.