(354) Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis after COVID-19 Vaccination

Background: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) following the COVID-19 vaccination have been reported extremely rarely.

Objectives: This study evaluated the short-term risk of SJS/TEN after COVID-19 vaccination.

Methods: Using the National Health Insurance Service database linked to the national COVID-19 vaccination database in Korea, we conducted a modified self-controlled case series study for event-dependent exposures and high event-related mortality. The eligible population included both unvaccinated and vaccinated patients, aged 19 years or older, diagnosed with SJS/TEN during a 911-day observation period spanning from January 1, 2021 to June 30, 2023. Exclusion criteria encompassed individuals with a history of SJS/TEN or erythema multiforme, those diagnosed with herpes simplex or mycoplasma infection, individuals receiving sulfonamides, antiepileptics, NSAIDs, allopurinol, nevirapine, or antibiotics, those diagnosed with lupus erythematosus or graft versus host disease, and those confirmed with COVID-19 before the index date. The post-vaccination risk period was defined as the period of days 1 through 35 following each vaccine dose and the remaining period as control period. Unbiased estimating equations were used to estimate the relative incidences (RIs) and their 95% confidence intervals.

Results: Among 970 patients with SJS/TEN during an observation period, 867 patients (89%) received at least one dose of a COVID-19 vaccine. Four patients were diagnosed with SJS/TEN on the day of vaccination, and 129 patients were diagnosed during the post-vaccination risk period. The RIs for SJS/TEN following any vaccine doses were 1.510 (95% CI, 0.623-3.657) on the day of vaccination and 1.117 (95% CI, 0.904-1.380) during the risk period. By vaccine dose, the RI on the day of the first dose vaccination was 3.467 (95% CI, 1.275-9.424), and the RI during the risk period following the first dose vaccination was 1.395 (95% CI, 1.021-1.910). An increased risk of SJS/TEN was not observed in association with the subsequent dose.

Conclusions: In this nationwide study, we observed an elevated risk of SJS/TEN on the day of the vaccination and during the 35-day risk period, specifically associated with the first dose of vaccination. Further investigations are needed to confirm the results of this study.