Erythema multiforme reactions after Pfizer/BioNTech (BNT162b2) and Moderna (mRNA-1273) COVID-19 vaccination: A case series

Background rates for severe cutaneous reactions in the US: Contextual support for safety assessment of COVID-19 vaccines and novel biologics

The global COVID-19 public health crisis has resulted in extraordinary collaboration to expeditiously develop vaccines and therapeutics. The safety of these biologics is closely monitored by the US Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention (CDC). Novel products may have limited safety data, and although serious medical outcomes associated with vaccination are rare, knowledge of background incidence rates of medical conditions in the US population puts reported adverse events (AEs) in perspective for further study. Although relatively minor vaccination skin reactions are common, rare instances of severe delayed hypersensitivity reactions such as erythema multiforme (EM), Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and SJS/TEN overlap syndrome may occur. To aid in the assessment of these events, we performed a literature search in PubMed and Web of Science on the background incidence of EM, SJS, SJS/TEN, and TEN in the US population and on published reports of these conditions occurring post-vaccination. The US background annual incidence rates per million individuals of all ages ranged from 5.3 to 63.0 for SJS, from 0.4 to 5.0 for TEN, and from 0.8 to 1.6 for SJS/TEN. Since these conditions may overlap, some studies reported rates for EM/SJS/TEN combined, however we did not find studies with exclusive EM incidence rates. The published literature, including studies of reports submitted to the FDA/CDC Vaccine Adverse Event Reporting System (VAERS), describes post-vaccination EM, SJS, SJS/TEN and/or TEN as rare occurrences. The vaccines most frequently associated with these conditions were measles, mumps, and rubella; diphtheria, tetanus, and pertussis; and varicella. The majority of VAERS reports of EM, SJS, SJS/TEN, or TEN occurred in children within 30 days of vaccination. This review summarizes background rates of these disorders in the general population and published AEs among vaccine recipients, to support safety surveillance of COVID-19 vaccines and other biologics.

Occurrence of erythema multiforme following COVID-19 vaccination: a review

The fast development of vaccines against the novel coronavirus disease is among the most critical steps taken to control this potentially fatal viral disease. Like other vaccines, the coronavirus disease 2019 (COVID-19) vaccines can also cause unwanted reactions. Erythema multiforme (EM) is among the oral mucocutaneous side effects of COVID-19 vaccines. This study aimed to comprehensively review the reported cases of EM since the global onset of COVID-19 vaccination. Data from 31 relevant studies regarding the type and dose of COVID-19 vaccines administered, time of initiation of symptoms, age, and gender of patients, site of involvement, patients' medical history, and treatment options were extracted. In total, 90 patients were identified with EM as a side effect of COVID-19 vaccination across studies. EM had the highest frequency after receiving the first dose of mRNA vaccines in older individuals. The first symptoms of EM appeared in less than 3 days in 45% and after 3 days in 55% of patients. EM is not a common side effect of COVID-19 vaccination, and fear of its occurrence should not impede vaccination.

A Systematic Review of Histopathologic Surveys on Mucocutaneous Biopsies in Patients Developed COVID-19 Vaccine-Related Dermatologic Manifestations

ABSTRACT

Coronavirus 2 is an infectious agent primarily identified as the cause of a pandemic viral pneumonia. With the mass vaccination against this virus, one of the health issues is the safety of currently available vaccines considering their adverse reactions. This systematic review was conducted to assess and summarize all reported data on histopathologic findings associated with mucocutaneous reactions that developed after COVID-19 vaccination for a better pathophysiology interpretation and clinical management of these reactions. A systematic search was performed in PubMed, Web of Science, and Scopus databases as well as Google Scholar engine for relevant English articles published till July 1, 2022. This review includes 131 studies with a total number of 287 cases. Eruptions that underwent a biopsy were mostly described as erythematous maculopapular, papulosquamous, vasculitis-like, lichenoid, or urticarial lesions. Histopathology revealed spongiosis, interstitial, and perivascular lymphohistiocytic infiltration, erythrocyte extravasation, parakeratosis, endothelial inflammation, and the like. Findings were highly consistent with morbilliform erythema, psoriasiform dermatosis, leukocytoclastic vasculitis, and lichenoid or urticarial drug reactions. The majority of these reactions had a mild nature and were primarily observed in patients with underlying health conditions. Microscopic evaluation was also consistent with transient inflammatory changes, and features like neutrophilic infiltrates, subcorneal pustules, and vasculopathy were less frequently reported than what seen in COVID infection. Therefore, dermatologic reactions developing after vaccination in the general population should not hinder a complete vaccination.