Pernio/chilblains are a painful abnormal reaction of the small blood vessels in the skin when exposed to cold temperatures. Chilblains usually occur several hours after exposure to the cold in temperate humid climates. The cold causes constriction of the small blood vessels in the skin and if rewarming of the skin happens too rapidly, there is leakage of blood into the tissues as the blood vessels do not respond quickly enough to this rewarming. Chilblains are not very common in countries where the cold is more extreme as the air is drier. The living conditions and clothing used in these climates are protective. Chilblains are more likely to develop in those with poor circulation, but chilblains are still common in those with good circulation.
Pernio appear as small itchy, red areas on the skin. Chilblains become increasingly painful as they get congested and take on a dark blue appearance. They may also become swollen. As they dry out, chilblains leave cracks in the skin so the risk of getting an infection increases. Chilblains are common on the toes, but can also affect the fingers and the face (especially the nose and ears). Chilblains are also common on areas of the feet exposed to pressure, such as bunions or where the toes are under pressure from tight shoes or where there are corns and callus.
Symptoms & Causes
Pernio starts during the winter (when the weather gets colder) – the initial symptoms include burning and itching in the area of the developing chilblain. These symptoms are often intensified when going into a warm room. There is often some swelling and redness. In many cases, the skin over the chilblain can break down and becomes a sore (ulcer). An infection may develop in the chilblain.
Chilblains often occur in some people every year, for the rest of their lives. In other’s, chilblains occur for several years and then just stop occurring. The reason for these patterns of occurrence of chilblains is not known. As they are more common in females, there may be a hormonal influence on the development of chilblains.
Factors that contribute to tendency to pernio include, a familial tendency, poor circulation, anemia, poor nutrition, hormonal changes, smoking, some connective tissue disorders and some bone marrow disorders. Damp living conditions may also increase the risk for chilblains.
Prevention & Treatment
Keeping your feet warm is an important way to prevent chilblains. Wearing warm footwear, including wool socks, wool lined boots, or even using foot warmers when going outdoors can all be helpful. Gradual rewarming of the feet when returning indoors is advisable. Rapid rewarming in front of a heater or fireplace can make the condition worse. Rapid temperature changes should be avoided.
Sometimes a daily low dose 81 mg (baby) aspirin can help. Prescription steroid cream can also help. It is also important to determine whether there is an underlying serious condition which should be treated.