Pseudo-frostbite on the fingers and toes, rash on the torso or limbs, vesicles, hives: COVID-19 also appears to cause skin damage in some patients.
The more the coronavirus spreads, the more it becomes clear that it does not only attack the respiratory tract. Numerous observations point to neurological, cardiac, gastrointestinal, vascular symptoms, etc.
And now reports on skin manifestations of the disease are increasing in turn, to the point that the American Dermatology Association has just launched a registry to list cases and paint a full picture of these signs. Other learned societies, such as the French Society of Dermatology, have also launched case calls.
A first Italian case study published in late March drew attention to the fact that 18 out of 88 patients studied had rashes, hives or chickenpox-like lesions. Since then, these observations have been confirmed and other signs have been added.
The National Institute of Excellence in Health and Social Services (INESSS) has just conducted a review of the scientific literature on this subject. “An increased number of cases of perniosis-like lesions [pseudo-engelure] would be seen in children, adolescents and young adults in the current COVID-19 pandemic, with no history of exposure to cold. Patients with these lesions are generally asymptomatic or sometimes report mild symptoms similar to COVID-19, which occurred before the lesions appeared, “said the report released on May 12, among others.
If children seem to be more affected, note that skin lesions have been observed in adults of all ages.
“Some skin manifestations seem more specific to COVID-19 and others less so. Lesions of the “pseudo-frostbite” type and vesicular rashes [de type varicelle] are probably the most specific, “says Dre Hélène Veillette, dermatologist at the CHU de Québec-Université Laval, who participated in the preparation of the INESSS report.
While many dermatologists around the world have observed an increase in some usually rare signs, including the famous “COVID toes” akin to frostbite, larger studies to establish causal links have yet to be made. carried out.
“Pseudo-frostbite seems to be a rather late manifestation in the history of the disease, continues Dre Night watch. As the current test consists in checking for the presence of the virus by PCR, it is often negative when the lesions appear. When serology becomes available, it will be interesting to see if these people have actually had the virus recently. “
Should we screen?
In Quebec, skin symptoms are not currently considered signs of COVID-19 and therefore do not give rise to screening.
“However, some doctors and learned societies advocate screening, first to identify the few cases that would be positive and then to better document this manifestation and the link with COVID in our population,” added the dermatologist.
For example, the Canadian Pediatric Surveillance Program has issued a public health alert regarding COVID-19 and skin manifestations in children. According to the organization, the presence of skin manifestations such as an unusual coloring of the toes or fingers (bluish or whitish hues, or swollen and red areas like frostbite) should encourage health professionals to screen for COVID -19, can we read in the INESSS report.
For their part, Italian doctors recently stressed, in The Lancet Infectious Diseases, that “children and adolescents with frostbite-like lesions, but being otherwise asymptomatic, should be screened for SARS-CoV-2, to help detect silent carriers. “
The mechanisms involved in these lesions must also be elucidated. “Each manifestation may have its own mechanism, but for pseudo-frostbite, it is certainly a vascular process,” says Dre Night watch. On the other hand, the involvement of the vessels can have different causes at the cellular level and this portion is still poorly understood in frostbite-like lesions. In most cases where a skin biopsy was performed, there was little specific inflammation around the vessels. “
One thing is certain, this virus plays on many tables…