摘要
Introduction:Coronavirus disease 2019(COVID-19)may be associated with various skin manifestations.Among them,figurate erythema(FE)is rare;only a few clinical reports have been published.Herein,we reported an unusual concentric FE lesions and their immunohistochemical profile in a patient with COVID-19.Case presentation:A 52-year-old woman was diagnosed with COVID-19.One month later,she developed asymptomatic annular erythematous concentric ring lesions on her inner right thigh.The margin of every ring increased in coloration,and the lesions then completely resolved in 2 weeks.A biopsy revealed vasculitis of small vessels,an increase in the fluorescence intensity of CD3 and CD45,and negativity for COVID-19 RNA.Discussion:The results showed an unusual FE that has a clinical mixed type between erythema annulare centrifugum and erythema gyratum repens;the physiopathological mechanism in the FE due to COVID-19 is unknown;one theory involves rapid viral passage into the cutaneous vascular system that triggers an immune and inflammatory response.Although the results exhibited a negative COVID-19 RNA in the tissue,the CD3^(+)/CD45^(+)lymphocyte infiltration could explain the clinical pattern as a direct inflammatory response in the small vessel or as a delayed immune response.Conclusion:Our findings suggest an immunohistochemical small vessel vasculitis pattern with an unusual clinical FE that differs from other types of COVID-19-associated FE or erythema reported previously.
