How COVID-19 Can Affect the Skin
In this country and around the world, we are seeing a variety of abnormal skin conditions in patients infected with Coronavirus Disease 2019 (COVID-19). It’s too early to determine if these skin issues are hallmarks of the virus or simply a result of the body’s immune response in fighting off the infection. Medications used to treat the disease may also play a role.
In the U.S., up to 20 percent of those infected have experienced some type of skin issue, much higher than the rate reported in China and Europe. We don’t yet know if the U.S. rate is truly higher or simply the result of better monitoring and reporting.
The good news: most of the conditions are not serious and will go away as the infection clears. Some, however, may require testing and monitoring.
Much of what dermatologists are seeing is anecdotal, meaning not yet proven or tested in a rigorous, scientific way. Since the pathogen is so new, we do not yet have enough data. But we are collecting it so we will be better able to quantify trends and causes in the future.
Here’s what we know about certain skin conditions so far:
COVID-19 may be causing some unique skin problems. Dr. Petronic-Rosic explains what is known so far. https://bit.ly/2zw6KRO via @MedStarWHC
COVID toes present as small red, purple or bluish patches on the toes. Occasionally, a blister may form, which can break and weep. It may be mildly uncomfortable and prickly or can sting or burn. It generally goes away after a few weeks with no repercussions.
The lesions resemble chilblains, a kind of pre-frostbite that occurs when skin remains cold and wet for long periods. COVID toes can also be referred to as pseudo frostbite—or false frostbite—since those affected are actually not being exposed to cold or wet conditions. Unlike true frostbite, it heals with no permanent damage.
Like so many aspects of this virus, it’s somewhat unusual. It seems to affect young people, including young adults and teenagers, some of whom have tested negative for the virus. They generally have no other symptoms and feel fine. This may be the reason it’s getting so much attention in the media, as patients and their parents share their stories.
Most of the reported cases come from people who have been directly or indirectly exposed to the virus. Since we know that some can carry the virus and yet have no other symptoms, we treat those with affected feet as potentially positive, encouraging virus testing and limited exposure to others. As more data comes in, this foot problem might turn out to be an early warning, unlike other skin conditions that generally appear later when the illness has taken hold.
The most common skin issue associated with this virus is a red rash, appearing most often on the torso and less so on the extremities. It is mildly itchy, lasts a few days, and disappears as the virus runs its course and the condition improves.
Pocks or Spots
More recently, we have seen other rashes emerge, including one that appears as small blisters or red, crusty spots very similar to chickenpox. With coronavirus, though, these spots rarely appear on the face—unlike true chickenpox, which often affects the face. And because it has affected people who’ve already had chickenpox or the vaccine, and test negative for the chickenpox virus, we are confident it comes from a different source.
Hives are not unusual in the aftermath of viral infections. They are generally caused by an immune system thrown off-balance by the disease. Hives are generally mildly itchy and last a few days with no significant after-effects.
Spots that resemble bruises or pressure sores are being seen in the sickest patients, those on ventilators to support their breathing. They appear on areas of the body where pressure is not an issue, one reason we suspect they may be unique to the virus.
These start as retiform purpura, a lacy bruise-like rash, when small blood vessels become inflamed and tiny clots develop within them. Retiform purpura can signal tissue damage that might eventually evolve to gangrene as the disrupted blood supply results in the cell death.
Skin disorders can occur in ventilated patients, often resulting from low blood pressure, a side effect of ventilation. However, the lacy, bruise-like lesions seen in COVID-19 patients are different and may be unique to the virus. Progression to gangrene generally appears only in the most gravely ill patients. It has resulted in some amputations.
In healthy people who do not have a severe response to the infection, most lesions will go away on their own with no damage left behind. When itching or discomfort become issues, we treat them symptomatically with antihistamines or topical steroids.
In the case of hives, because they can put the patient at risk of a larger allergic reaction, we tend to be more aggressive with treatment to head off complications. We also know that NSAID medications, like aspirin and ibuprofen, can make hives worse, so we take steps to ensure the patient avoids NSAIDs until the hives clear.
If You Experience a Skin Issue
A simple way to get any skin condition evaluated is through a MedStar Health Video Visit with a dermatologist. During this pandemic, we are seeing most of our patients remotely—as many as 60–70 per day, compared to only two or three urgent patients in person.
The video technology is very easy to use, accessible, and best of all it can help put your mind at ease. We use it to make an examination and assess history and condition. We are also training our patients to take high-quality still photographs of the affected area, a powerful complement to the video visit.
During the session, we can look for warning signs of something serious, ask the right questions to gauge symptoms and severity, and instruct the patient to perform simple tasks that help inform our decision-making.
What’s Going On?
We don’t know all the mechanisms behind the skin problems, so it’s too early to speculate.
However, we know that certain hallmarks of the disease can cause skin problems. One big suspect is microthrombi, or tiny blood clots widely reported in patients around the world.
These clots are unlike those experienced in everyday life due to age, cardiac disease or poor circulation. Rather, they can occur in almost any part of the body and are a known contributor to death from the virus because they interfere with the healthy function of vital organs.
Viral infections also stimulate the release of cytokines, proteins that play an important role in regulating the life process. They tell cells what to do and when to do it. At the extreme end of the immune response, a sudden, systemic cytokine release—the cytokine storm—can quickly overwhelm the body, potentially triggering high fever, bleeding, low blood cell counts, and multiple organ failure.
But even a mild immune response can affect normal cytokine levels, which may lead to some of the skin lesions we are seeing. A link is yet to be proven.
Data for Knowledge
As we learn more and collect more data, some of these skin effects may be added to the list of other known coronavirus symptoms, like fever, cough, shortness of breath, and loss of taste or smell.
The professional dermatology community is working hard to speed that process. For example, the American Academy of Dermatology has launched a registry, collecting details about skin conditions potentially associated with the novel virus. It is tracking thousands of cases and related details.
We are also seeing unprecedented speed in information sharing. As in many other medical specialties, our journals are fast-tracking papers and articles related to the novel virus, giving physicians swift access to new trends and information.
SARS-CoV-2, the virus that causes COVID-19, is dramatically different from most pathogens we have seen before—so, it makes sense that some of its symptoms are different, too. These unusual skin conditions certainly qualify.
This pandemic evolved lightning-quick—only four months ago, there were no reported cases in the U.S. The situation has advanced and changed rapidly. Fortunately, the science is also developing very quickly.
The answers we don’t have today, we may have tomorrow.