In this study, the investigator designed a prospective interventional study in order to collect blood samples and skin lesion biopsy at significant time points in patients who present a skin lesion. The intervention in this study is limited to some blood samples and skin biopsies.
Two 7 mL tubes of blood will be collected at consultant time for essentially serological test for the SARS-CoV-2 and for analysing certain populations of white blood cells. The second additional blood sample of 7 mL will be collected around day 15 after inclusion in a dry tube to perform a serological test for SARS-CoV-2 at a distance from the onset of skin signs.
A biopsy for histological study is usually done in patients with acrosyndrome. This is why this type of biopsy will be done as a routine care of these patients. An immunohistochemical study could complete the histological explorations using an anti-coronavirus antibody if arguments in favour of SARS-CoV-2 are demonstrated. In this study, patients who accept and sign informed consent will be proposed a skin biopsy on a characteristic lesion for freezing. This biopsy can be used for transcriptomic analysis. This may allow a better understanding of the mechanisms of the disease.