ABSTRACT
BACKGROUND: Many peculiar skin changes have been described in relation to both coronavirus disease 2019 (COVID-19) infection and vaccination. OBJECTIVE: This paper provides an overview of these dermatologic manifestations, focusing on their dermatopathological appearances. RESULTS: Most COVID-19 patients develop variegated maculopapular eruptions with a combination of histological patterns commonly including keratinocyte apoptosis and eosinophilia. Urticaria-like lesions often show a combination of spongiotic and lichenoid patterns and are more frequent in individuals with severe disease. Vesicular lesions can be disseminated; in some cases, they become pustular and in others show dyskeratosis and a peculiar form of ballooning. Some patients develop vesicular Grover disease on the trunk. Young patients with a strong immunological response can eliminate the virus easily but may develop chilblains as a consequence of the high interferon response. Conversely, older individuals with immunosenescence and a tendency toward hypercoagulability can present livedoid and ischemic areas. Regarding COVID-19 vaccination, hypersensitivity reactions are most frequent, including "COVID-arm." Nonetheless, a combination of local and systemic cutaneous manifestations (reactogenicity) is commonly seen. Histopathologically, lichenoid and spongiotic changes and a variable number of eosinophils are typical of rashes characterized by papules and plaques. Other dermatological side effects of COVID-19 vaccination include lesions mimicking well-defined dermatoses such as lichen planus or bullous pemphigoid and triggering of collagenous diseases. CONCLUSION: Well-characterized skin manifestations of coronavirus disease 2019 (COVID-19) include chilblains, livedo necrotic lesions, vesicular eruptions, urticarial lesions, and maculopapular eruptions. Hypersensitivity reactions are common after SARS-CoV2 mRNA vaccination. Vaccine reactions may also mimic other dermatosis such as bullous pemphigoid or lichen planus, stimulate herpes reactivation, or trigger the development of autoimmune diseases.
ABSTRACT
Background Many peculiar skin changes have been described in relation to both coronavirus disease 2019 (COVID-19) infection and vaccination. Objective This paper provides an overview of these dermatologic manifestations, focusing on their dermatopathological appearances. Results Most COVID-19 patients develop variegated maculopapular eruptions with a combination of histological patterns commonly including keratinocyte apoptosis and eosinophilia. Urticaria-like lesions often show a combination of spongiotic and lichenoid patterns and are more frequent in individuals with severe disease. Vesicular lesions can be disseminated;in some cases, they become pustular and in others show dyskeratosis and a peculiar form of ballooning. Some patients develop vesicular Grover disease on the trunk. Young patients with a strong immunological response can eliminate the virus easily but may develop chilblains as a consequence of the high interferon response. Conversely, older individuals with immunosenescence and a tendency toward hypercoagulability can present livedoid and ischemic areas. Regarding COVID-19 vaccination, hypersensitivity reactions are most frequent, including “COVID-arm.” Nonetheless, a combination of local and systemic cutaneous manifestations (reactogenicity) is commonly seen. Histopathologically, lichenoid and spongiotic changes and a variable number of eosinophils are typical of rashes characterized by papules and plaques. Other dermatological side effects of COVID-19 vaccination include lesions mimicking well-defined dermatoses such as lichen planus or bullous pemphigoid and triggering of collagenous diseases. Conclusion Well-characterized skin manifestations of coronavirus disease 2019 (COVID-19) include chilblains, livedo necrotic lesions, vesicular eruptions, urticarial lesions, and maculopapular eruptions. Hypersensitivity reactions are common after SARS-CoV‑2 mRNA vaccination. Vaccine reactions may also mimic other dermatosis such as bullous pemphigoid or lichen planus, stimulate herpes reactivation, or trigger the development of autoimmune diseases.