Vascular cutaneous manifestations of COVID-19 and RNA viral pathogens: a systematic review

Background COVID-19, the widely recognized and highly contagious respiratory tract infection, has had a substantial impact on the field of dermatology since its emergence in 2019. SARS-CoV-2, the causative virus of COVID-19, is classified as an RNA virus. Various skin-related symptoms have been reported in patients with COVID-19, most notably the distinctive purple-red acral rash resembling chilblain lesions, commonly referred to as 'COVID toe'; similarly, skin-related symptoms have been observed in connection with other RNA viruses.Objectives To explore the relationship between RNA viruses and their associated vascular cutaneous manifestations vs. those observed in patients infected with SARS-CoV-2.Methods A systematic literature review was conducted using PubMed and medical subject heading terms related to RNA viruses and related skin manifestations.Results In total, 3994 patients diagnosed with COVID-19 presenting with skin rashes were included. Chilblain-like lesions were most frequently observed (30.2%), followed by erythematous maculopapular/morbilliform rashes (9.1%) and urticarial rashes (4.7%). Of 8362 patients diagnosed with RNA viruses, more than half of the skin findings reported were erythematous/maculopapular/morbilliform rashes (52.3%), followed by unspecified (11.3%) and purpuric rashes (10.6%).Conclusions When comparing RNA viral infections with COVID-19 infection, we observed similarities in the reported skin manifestations and their presumed pathways, with many implicated in the proinflammatory response. Owing to the wide range of cutaneous symptoms associated with RNA viruses and our currently limited understanding of the underlying mechanisms, additional research is warranted to investigate the pathology behind viral-induced skin lesions. This review explores the vascular cutaneous manifestations of RNA viruses, comparing them with those of SARS-CoV-2. COVID-19 has significantly impacted on dermatology, with distinctive skin symptoms like 'COVID toe'. Among 3994 patients with COVID-19 who had skin rashes, chilblain-like lesions (30.2%) were the most common. Among 8362 patients with another RNA virus infection, erythematous/maculopapular/morbilliform rashes (52.3%) predominated. Similar skin manifestations and proinflammatory pathways were observed in RNA viral infections and infections with COVID-19.