Unraveling COVID-19-vaccination-induced bullous pemphigoid: a case report and review of the literature

Background Coronavirus disease 2019 vaccines have been instrumental in combating the global pandemic, yet their potential side effects, including autoimmune conditions such as bullous pemphigoid, remain an area of concern. This case highlights the development of bullous pemphigoid following coronavirus disease 2019 vaccination and includes a comprehensive review of similar cases reported in the literature, emphasizing its novelty and clinical significance. Case presentation An elderly British man in his 80s with type 2 diabetes mellitus developed blistering lesions 21 days after receiving his third dose of coronavirus disease 2019 vaccine (Moderna). Clinical examination revealed erythematous plaques and bullae on the trunk and limbs. Histopathological evaluation and immunofluorescence confirmed the diagnosis of bullous pemphigoid. Treatment included corticosteroids, doxycycline, and immunosuppressants. Despite initial improvement, a severe flare-up necessitated hospitalization and wound care management. A systematic review identified 50 reported cases of bullous pemphigoid linked to coronavirus disease 2019 vaccination, with the Pfizer-BioNTech vaccine implicated in most cases (64%), followed by Moderna (18%). Symptom onset typically occurred after the first dose in 52% of cases. Conclusion This case underscores the need for vigilance regarding autoimmune phenomena such as bullous pemphigoid following coronavirus disease 2019 vaccination. Awareness of such potential adverse effects is crucial to ensure timely diagnosis and management, ultimately contributing to patient safety and guiding future vaccine development.