Bullous pemphigoid with subsequent milia en plaque following administration of the Pfizer-BioNTech COVID-19 vaccine

ABSTRACT

We present the case of a 68-year-old woman who presented with a blistering skin eruption 5 days after the administration of the first dose of Pfizer-BioNTech mRNA COVID-19 vaccine. Examination revealed tense bullae in a localized distribution confined to the dorsal aspect of her hands, forearms and ears only. This was preceded by severe pruritus. She had no mucosal involvement and was otherwise systemically well. She had a background of chronic obstructive pulmonary disease and hypercholesterolaemia with no previous history of COVID-19. Skin biopsy revealed a subepidermal bulla containing numerous eosinophils in keeping with bullous pemphigoid (BP). The diagnosis was confirmed with a positive direct immunofluorescence (IF) which showed linear IgG and C3 deposition at the basement membrane zone. Indirect IF was positive for anti-BP180 and anti-BP230. The patient was treated with oral prednisolone and doxycycline to good effect She proceeded to have the second dose of the Pfizer-BioNTech vaccine while on treatment and did not experience a flare of BP. However, a week later, she developed erythematous annular plaques with milia over the dorsi of her hands. Skin biopsy revealed multiple milia within the papillary dermis in keeping with milia en plaque. To to our knowledge, this is the first case of a patient developing BP with subsequent milia en plaque following the Pfizer-BioNTech mRNA COVID-19 vaccine (Damiani G, Pacifico A, Pelloni F, Iorizzo M. The first dose of COVID-19 vaccine may trigger pemphigus and bullous pemphigoid flares is the second dose therefore contraindicated? J Eur Acad Dermatol Venereol 2021;35 e645-7). She has since been weaned off systemic treatment for BP;however, she continues to require ongoing input for the management of milia en plaque.