dcyphr | Chilblain‐like lesions on feet and hands during the COVID‐19 Pandemic


The novel coronavirus, SARS-CoV-2, is causing the COVID-19 pandemic. Many of the common symptoms of the coronavirus include cough, fever, headache, soreness, and more. In Spain, dermatologists have been treating patients virtually. The researchers noted an increasing number of cases of lesions that resemble chilblains. Chilblains are skin sores that show up when small blood vessels become inflamed from the cold. The majority of patients were children or young adults. They initially had red lesions like chilblains. About a week later, the lesions began to appear as purple spots and were flatter. There was some discomfort and pain if one touched the lesions. Most patients had mild symptoms or no symptoms of the coronavirus. Most patients had no respiratory conditions. 


The researchers aim to make dermatologists aware of a possible symptom of the coronavirus. Particularly, skin lesions may form. 


The researchers presented six case studies. All of them had skin lesions in the toes, heels, and/or toes. All of them presented with some indication of the coronavirus, either through symptoms or an X-ray. However, not all of them could be tested for the virus. A summary of the results are in Table 1.


The researchers cannot confirm that the lesions are due to the coronavirus. However, these lesions are rare, and there are a large number of consultations on these lesions. Furthermore, these patients are in Spain, where there are a large number of cases. Thus, it is highly possible that there is a correlation between the lesions and the coronavirus. Other countries, including Italy and France have also reported similar symptoms in patients.

The researchers hypothesize that the lesions may be a late indication of COVID-19. At the time that lesions were reported, Spain was several weeks after the peak number of cases. Also, patients often reported contacts with COVID-19 several weeks before noticing the lesions. The negative PCR test in some patients can be due to no infection, a false negative, or that the patient has already largely recovered.

Dermatologists are not sure if the lesions are due to vasculitis (the inflammation of blood vessels) or microthrombi (small clots). They indicate that the lesions are different from various forms of ischemia (low blood flow). At this time, dermatologists are not able to biopsy the lesions.

Researchers still need to confirm this hypothesis. Meanwhile, the lesions may help diagnose patients who are asymptomatic. When the opportunity arises, a reverse transcription polymerase chain reaction (RT-PCR) test and IgM - IgG serological tests need to be done on the patients.