During the COVID-19 pandemic, people have been experiencing itchy and painful red-purple lesions on their toes. These resemble chilblains, which occur when blood vessels lining the skin are exposed to cold temperatures.
COVID toes have been a topic of significant public interest, rivaling the more recognized unique symptoms of loss of smell and taste and shortness of breath. However, this phenomenon may have nothing to do with COVID-19.
Symptoms
CDC has updated its list of symptoms of COVID-19 to include skin conditions that some people are reporting as “COVID toes.” Although these atypical symptoms are not related to the virus, they can be scary for those experiencing them.
Patients have reported red-purple, swollen and itchy bumps on the feet, especially the toes but also the heels and fingers. They resemble perniosis, a common cold weather condition that can cause swollen and discolored fingers and toes. The rash can be caused by standing on wet, cold ground and is not the same as frostbite, which occurs when the skin freezes.
The lesions, sometimes called COVID-19 toes, are erythematous to purple purpuric macules and papules that develop on the dorsal phalanges of the toes and sometimes the nails and digital pulps. They can be accompanied by itching and burning sensations and may last for 14 days or more. They are not recurrent and do not persist when the patient stops having contact with the affected person.
While these atypical symptoms have been reported in patients who have tested positive for COVID-19, other etiologies should be considered. They occur most frequently in children and young adults and often resolve spontaneously. They may be associated with a negative serology, but the recent literature suggests that the excessive interferon-alpha response of these patients can clear the virus before humoral immunity develops.
Diagnosis
During the COVID-19 pandemic, several unusual skin manifestations have been observed, including erythematous, itchy lesions that develop on the toes (COVID toes). Similar to perniosis or chilblains, the bumpy, red-purple, abrasion-like, and itchy symptoms are thought to be caused by the virus’s effect on small blood vessels in the feet.
In one case, a 59-year-old man experienced painful cyanosis of the toes, and histopathology showed a capillary vasculopathy with superficial fibrin thrombi occluding dermal papillae. He had close contact exposure to two family members who developed respiratory illness and documented SARS-CoV-2. His upper respiratory symptoms did not persist, and nasal swab RT-PCR tests for the virus were negative.
The patient’s symptoms were treated with 2% nitroglycerin cream daily, and his toes improved with the medication. He reported that his toes felt numb and tingled, and that the pain decreased after a few weeks.
The patient was able to return to work and his toes healed within four months. The researchers say that understanding these rare manifestations of COVID-19 could help foot and ankle specialists recognize them earlier and respond with appropriate treatment. They also note that MRI scans of patients with this condition show a pattern of distal-to-proximal bone marrow edema in the toes, which is consistent with vascular issues. The researchers queried Google Trends to establish relative search volumes for unique symptomology associated with the COVID-19 pandemic, including loss of smell, loss of taste, and shortness of breath.
Treatment
COVID toes is a rare symptom that has gained media attention because it appears to be related to the coronavirus pandemic. It can affect anyone, but it is most common in children, teens, and young adults. It develops when the small blood vessels in the skin become exposed to cold temperatures and it can make the toes appear red or purple, causing them to be swollen and irritated. It’s similar to chilblains, which is a cold weather condition that occurs when the toes are exposed to cold temperatures and can also cause them to be swollen and itchy.
The symptoms of COVID toes last for about 14 days and then resolve spontaneously. They can be difficult to diagnose because they can look like a variety of different conditions, such as psoriasis and shingles. They can range from erythematous to purple purpuric macules, papules, and vesicles. These lesions occur mainly in children and adolescents and are often associated with microthrombotic events in the extremities. Laboratory tests are typically negative.
COVID toes may be a false alarm because it can be caused by other illnesses, such as chilblains, and not by the COVID-19 virus. It can also be caused by stress or overexposure to the cold. It’s important for patients to contact their doctor right away if they are experiencing this symptom so that their doctor can determine the cause and provide them with treatment options.
Prevention
During the COVID-19 pandemic, many people developed painful, discolored toes that were initially thought to be the symptom of COVID-19 infection. The condition was dubbed “COVID toes” because the lesions were similar in appearance to the skin condition chilblains. The symptoms were associated with a fever and often occurred when a person was indoors, where the air was colder than usual.
The toe symptoms were not the result of COVID-19 virus infection, but rather a normal response to an exposure to the coronavirus. Despite the lack of direct evidence linking the toe symptoms to the virus, there was wide-spread media coverage, leading to intense public interest in this unique symptomology.
Google Trends analysis was used to establish relative search interest in this symptom at the height of the pandemic.
While it is still not clear what causes COVID toes, researchers believe the toe changes are the result of a specialized immune system response to the coronavirus that targets blood vessels. This triggers an antiviral response, which produces a large amount of type I interferon, an important immune molecule that interferes with every step of the coronavirus’s replication cycle. The investigators believe that COVID toes may represent a visible expression of this critical interferon response and may identify individuals who are naturally resistant to the severe manifestations of SARS-CoV-2 infection.