Type I Interferon Signature in Chilblains Following SARS-CoV-2 mRNA Vaccine: A Case Report

Global prevalence and clinical manifestations of cutaneous adverse reactions following COVID-19 vaccination: A systematic review and meta-analysis

Although vaccination is widely accepted as an effective method of preventing and controlling the COVID-19 pandemic, many people are concerned about possible cutaneous side effects which can delay or prevent them from being vaccinated. The objectives of this systematic review were to assess the global prevalence and clinical manifestations of cutaneous adverse reactions following COVID-19 vaccination. PubMed and Scopus databases were searched for articles published from January 1, 2019, to December 31, 2021, and reference lists for each selected article were screened. Case reports, case series, observational studies, and randomized controlled trials that provided information on cutaneous adverse reactions following COVID-19 vaccines were included. A total of 300 studies were included in a systematic review of which 32 studies with 946,366 participants were included in the meta-analysis. The pooled prevalence of cutaneous manifestations following COVID-19 vaccination was 3.8% (95% CI, 2.7%-5.3%). COVID-19 vaccines based on the mRNA platform had a higher prevalence than other platforms at 6.9% (95% CI, 3.8%-12.3%). Various cutaneous manifestations have been reported from injection site reactions which were the most common (72.16%) to uncommon adverse reactions such as delayed inflammatory reactions to tissue filler (0.07%) and flares of pre-existing dermatoses (0.07%). Severe cutaneous reactions such as anaphylaxis have also been reported, but in rare cases (0.05%). In conclusion, cutaneous adverse reactions are common, especially in those receiving mRNA vaccines. Most reactions are mild and are not contraindications to subsequent vaccination except for anaphylaxis, which rarely occurs. COVID-19 vaccination may also be associated with flares of pre-existing dermatoses and delayed inflammatory reactions to tissue filler. Patients with a history of allergies, pre-existing skin conditions, or scheduled for filler injections should receive additional pre-counseling and monitoring. A better understanding of potential side effects may strengthen public confidence in those wary of new vaccine technologies.

SARS-CoV-2 vaccine-related cutaneous manifestations: a systematic review

To date, over 250 million people have been reportedly infected by COVID‐19 disease, which has spread across the globe and led to approximately 5.1 million fatalities. To prevent both COVID‐19 and viral transmission, DNA‐based/RNA‐based vaccines, non‐replicating viral vector vaccines, and inactivated vaccines have been recently developed. However, a precise clinical and histological characterization of SARS‐CoV‐2 vaccine‐related dermatological manifestations is still lacking. A systematic review of 229 articles was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines, in order to provide an extensive overview of SARS‐CoV‐2 vaccine‐related skin manifestations. Data on demographics, number of reported cases with cutaneous involvement, vaccine, and rash type (morphology) were extracted from articles and summarized. A total of 5941 SARS‐CoV‐2 vaccine‐related dermatological manifestations were gathered. Local injection‐site reactions were the most frequently observed, followed by rash/unspecified cutaneous eruption, urticarial rashes, angioedema, herpes zoster, morbilliform/maculopapular/erythematous macular eruption, pityriasis rosea and pityriasis rosea‐like eruptions, and other less common dermatological manifestations. Flares of pre‐existing dermatological conditions were also reported. Cutaneous adverse reactions following SARS‐CoV‐2 vaccine administration seem to be heterogeneous, rather infrequent, and not life‐threatening. Vaccinated patients should be monitored for skin manifestations, and dermatological evaluation should be offered, when needed.