What are chilblains?
Posted: Aug 27, 2020
Chilblains are a common problem of the feet in the colder climates. They are due to a poor reaction of the small blood vessels to changes in temperature. Normally when the feet get cold the small blood vessels in the skin constrict to help keep the body’s core temperature at a stable level. Normally, when the foot warms up, these blood vessels open up to bring more circulation to the skin to disperse the heat. In a chilblain, those small blood vessels remain closed and do not open up immediately. This results in waste products accumulation in the skin which then cause the release of inflammatory mediators. Eventually the blood vessels do open up, resulting in an inflammatory reaction.
The cause of this problem with how the blood vessels react to the change in temperature is not known. They just seem to happen in some people and not in others. They are more common in females which indicates that there may be a hormonal component to them. They do, however, occur in males, but just less often. They are not related to poor circulation as both those with good and poor circulation get them. They also may occur for a number of years and then just stop occurring for no reason. The only thing that is clear is the relationship to the colder climates. They are unheard of in the warmer climates.
A recent particular oddity that has appeared recently is that there is a very high prevalence of chilblains in those with COVID-19. The coronavirus infection does increase the reactivity of the vascular system, so it could be seen how this might predispose to chilblains as they are an issue of the reactivity of the small blood vessels. However, some have disputed this by suggesting that the chilblains may not be directly related to COVID-19 but are more an issue of the lifestyle changes, such as being barefoot more in centrally heated homes as a result of the lockdown associated with the pandemic. The clinical features and management of the chilblains associated with COVID-19 is the same as the regular type of chilblains.
While chilblains predominately affect the toes, they do occasionally affect the nose and ears. They initially appear as red and itchy lesion on the toes that are painful. If they become chronic and keep occurring they take on a dark bluish color.
The ideal treatment for chilblains is to not get them in the first place. They can be prevented by keeping the feet warm with good shoes and socks. If the feet do get cold, then let them warm up slowly so that the blood vessels are given a chance to open up as they adapt to the warmth. If a chilblain does occur, the feet still need to be protected to prevent it from becoming chronic. If the skin is broken, then proper wound dressings should be used to prevent or control any infection. There are various creams that can be used to stimulate the circulation to remove the waste products that have accumulated in the skin.
Craig Payne is a University lecturer, runner, cynic, researcher, skeptic, forum admin, woo basher, clinician, rabble-rouser, blogger and a dad.