Cutaneous manifestation of COVID-19: What have we learned an year into the pandemic?

Coronavirus disease-19 (COVID-19) is an emerging health situation caused by the "severe acute respiratory syndrome coronavirus 2" (SARS-CoV-2). The ongoing COVID-19 pandemic which emerged from the Chinese city of Wuhan in December 2019 has spread to over 188 countries and infected over 100 million people across the globe in over one year. Most common symptoms of COVID-19 include fever and respiratory illness. Among extrapulmonary signs associated with COVID-19, dermatological manifestations have been increasingly reported from different geographical regions. The exact incidence or prevalence of COVID-19 associated skin manifestation remains largely unknown and the pathophysiological mechanisms are still unclear. In this article, we have attempted to give a comprehensive overview of what has been learned an year into the pandemic on the epidemiology, clinical and histopathological features, pathophysiological mechanisms and clinical management of COVID-19 associated cutaneous manifestations.

[Cutaneous Manifestation of COVID-19: What Have we Learned an Year Into the Pandemic?] / [Artículo traducido] Manifestaciones cutáneas de la COVID-19: ¿Qué hemos aprendido tras un año de pandemia?

Coronavirus disease-19 (COVID-19) is an emerging health situation caused by the "severe acute respiratory syndrome coronavirus 2" (SARS-CoV-2). The ongoing COVID-19 pandemic which emerged from the Chinese city of Wuhan in December 2019 has spread to over 188 countries and infected over 100 million people across the globe in over one year. Most common symptoms of COVID-19 include fever and respiratory illness. Among extrapulmonary signs associated with COVID-19, dermatological manifestations have been increasingly reported from different geographical regions. The exact incidence or prevalence of COVID-19 associated skin manifestation remains largely unknown and the pathophysiological mechanisms are still unclear. In this article, we have attempted to give a comprehensive overview of what has been learned a year into the pandemic on the epidemiology, clinical and histopathological features, pathophysiological mechanisms and clinical management of COVID-19 associated cutaneous manifestations.

Mucocutaneous Findings of Multisystem Inflammatory Syndrome in Children: A Single-Center Experience.

This descriptive study aimed to evaluate the frequency and the types of mucocutaneous manifestations associated with multisystem inflammatory syndrome in children (MIS-C). A cohort of 49 patients was reviewed. There were 6 patients (12.2%) whose mucocutaneous findings were observed by the clinicians on admission, whereas 26 (53%) patients had at least one of the histories of rash or desquamation associated with fever before the admission. Exanthems in our experience demonstrated a variety of morphologies, including morbilliform, urticarial, petechial, and maculopapular forms. Mucosal involvement (conjunctivitis and strawberry tongue) was observed only in 2/6 (34%) patients. In the coronavirus disease 2019 pandemic era, while evaluating the criteria for MIS-C, the history of previous cutaneous findings given by parents/caregivers is also important. There was no pathognomonic rash for MIS-C and a variety of cutaneous findings with a short lifespan can be associated with MIS-C.

Synthesis of the Data on COVID-19 Skin Manifestations: Underlying Mechanisms and Potential Outcomes.

The incidence of coronavirus disease 2019 (COVID-19)-related skin manifestations has progressively grown, in parallel with the global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spreading. The available evidence indicates that cutaneous signs are heterogeneous and can be divided as follows: a) erythematous rashes, b) lesions of vascular origin, c) vesicular rashes, d) urticarial rashes, and e) acute generalized exanthematous pustulosis (AGEP), erythema multiforme (EM) and other polymorphic/atypical reactions. Most cutaneous manifestations appear simultaneously or after respiratory and/or systemic symptoms such as fever, even if rarely urticaria has been reported as the first sign of the disease. It has been proposed that erythematous and vesicular rashes, as well as urticaria, are the result of immunological activation against Sars-CoV-2, similarly to other viral exanthems; alternatively, reactivation or co-infection of herpesviruses and drug hypersensitivity represent possible etiologic diagnosis that has to be considered. Regarding lesions of vascular origin, ischemic ones are the result of systemic hypercoagulability established in severe infections, whereas chilblains seem to be linked to the type I-interferon massively produced to halt virus replication. AGEP is triggered by drugs, whereas EM could represent a delayed immune response to the virus or a hypersensitivity reaction to drugs elicited by the inflammatory process built to fight the infection. A further pathogenic hypothesis is that the virus, or its particles detected in the skin (particularly in endothelium and eccrine glands), could be responsible for certain skin reactions, including chilblains and EM. From the available data, it appears that chilblains are correlated with younger age and less severe disease, while ischemic manifestations occur in the elderly with severe infection. In conclusion, larger studies are needed to confirm the suggested pathogenetic mechanisms of COVID-19-related skin reactions and to determine the potential prognostic significance of each one.