Chilblains, also known as pernio and perniosis, are skin lesions that appear in response to exposure to cold temperatures. They begin as a red and itchy bump, typically on the fingers, toes, nose, or ears and resolve within 1-2 weeks or sooner if cold temperatures are avoided. In some cases these initial lesions may develop into blisters, scabs, or even ulcers.
Chilblians develop when cold temperatures cause capillaries to constrict in the peripheral extremities, but it is unknown why some individuals are more susceptible to developing them than others. Some predisposing factors include family members that develop chilblains, other peripheral vascular diseases brought on by smoking, diabetes, or hyperlipidemia, abnormally low body weight, hormonal changes, certain bone marrow diseases, and connective tissue disorders such as lupus.
This condition is most common in the very young and very elderly. In infants, it tends to resolve with age, while it tends to become a chronic condition in elderly persons.
Most cases of chilblains will resolve on their own without complications and do not require medical intervention. In severe cases, a topical steroid may be prescribed to reduce the itch and vasodilators such as nifedipine and diltiazem may be used to improve circulation.
The most important measure to take if you are prone to chilblains, however, is prevention. Avoid exposure to extreme temperatures, and if you do get cold, do not aggressively re-warm with hot water as this can exacerbate the lesions. Contact your dermatologist if the lesions blister or turn into ulcers as this can lead to infection and permanent damage, or if they persist through warmer seasons as this may indicate a different disease process.