Chilblains (also known as pernio) are itchy or tender red lumps on extremities of the body: fingers, toes, ears and nose. They occur after exposure to cold.
Several hours after exposure to cold, damp weather, the blood vessels in the fingers and toes tighten up and get smaller (called vasoconstriction) to keep the warm blood as far away from the skin as possible, as this is where heat is lost. When returning to a warm environment from the cold, these blood vessels expand again, but can get inflamed (called vasculitis) if this happens too quickly. This causes itch and burning in the affected area. Small reddish lumps can appear on the skin, which may become painful or blistered. In those with skin of colour, chilblains may look purple-ish or even present as a brown patch of skin. If they’re untreated, chilblains can swell and form blisters, with a risk of ulcers, scarring and infection. But usually, if extremities are warmed, they will get better on their own in a few weeks.
While children and the elderly are most commonly affected, other age groups are not immune to this problem. Chilblains are more common in people with a family history of susceptibility and those who have problems with their blood circulation. Smoking, diabetes and high cholesterol can lead to poorer blood circulation. People who are underweight or have diseases that affect connective tissue (such as lupus) are also at increased risk of chilblains.