Incident bullous pemphigoid in a psoriatic patient following mRNA-1273 SARS-CoV-2 vaccination.

Abstract

Diverse phenotypes of cutaneous reactions were reported after the rapidly growing number of people receiving mRNA-based SARS-CoV-2 vaccines.1 Herein, we report the development of bullous pemphigoid (BP) with severe palmoplantar involvement in a psoriatic patient following the first dose of the mRNA-1273 (Moderna) vaccine administration. A 39-year-old man with stable psoriasis controlled by topical Chinese medicine (indigo naturalis) presented with multiple pruritic and tense bullae on bilateral hands and feet 1 month after receiving the first dose of mRNA-1273 vaccine (Fig. 1a–c). There were no vesicular or bullous lesions but red urticarial papules and plaques on the trunk (Fig. 1d,e). Oral methylprednisolone was prescribed from the local clinic for a week but his skin lesions still progressed. Histopathologic findings of the left foot skin showed a subepidermal bulla containing eosinophilic infiltration and focal re-epithelialization (Fig. 2a). Direct immunofluorescence study revealed linear deposits of C3 and IgG at the dermo-epidermal junction (Fig. 2b). Indirect immunofluorescence analysis (Euroimmun, Lübeck, Germany, positive cut-off value: 1 : 10) demonstrated a positive titre of 1 : 40 for anti-basement membrane zone antibodies. The clinical and pathologic presentations supported the diagnosis of BP. Intravenous methylprednisolone (1 mg/kg/day) for 4 days followed by a 9-day course of oral methylprednisolone (0.5 mg/kg/day) plus doxycycline (100 mg twice daily) were administered, with rapid improvement and resolution of all bullae. In the COVID-19 pandemic, new development or flares of existing BP after the administration of the mRNA-based vaccines have been reported.2, 3 In addition, cases of BP have been reported following other vaccines like the herpes zoster vaccine.4 To the best of our knowledge, this may be the first well-described case reporting newly developed BP in patient with underlying psoriasis following mRNA-1273 vaccine administration. Unlike the typical presentations of BP with pruritic bullae usually on the trunk and proximal flexural sites such as axillae and groins, our case presented with tense and haemorrhagic vesicles and bullae in a palmoplantar distribution. Though the pathogenesis is not clear, the non-specific vaccine-induced immune response may trigger symptoms development in patients with subclinical BP.5 The hypothesized autoantibodies' cross-reaction between the implicated vaccines and basement membrane antigen was less likely because of no known structural similarities.5 Intriguingly, in psoriatic patients, Krajewski et al. reported one case of disease flare-up after the BNT16B2b2 COVID-19 mRNA vaccination.6 Damiani et al.,7 by contrast, demonstrated four psoriatic patients under biologic agents treatment were safely received the BNT16B2b2 vaccine without exacerbation of their diseases. In our case, no flare of underlying psoriasis was observed after receiving mRNA-1273 vaccine. On the other hand, a previous meta-analysis has indicated a significant association between psoriasis and BP.8 Whether the new development of BP following the mRNA-1273 vaccine administration is a coincidence or is triggered by the vaccine-induced immune reaction is hard to elucidate. For the rarity of these events and the uncertainty of causality, the benefits of complete vaccination may still outweigh the risk of BP reaction.9 In summary, our observation describes the development of BP in a psoriatic patient following the first dose of mRNA-1273 SARS-CoV-2 vaccination. There may be a true association between BP development and mRNA-based SARS-CoV-2 vaccination. It suggested that COVID-19 vaccines may trigger a flare of pre-existing inflammatory diseases or even a new transitory disease.2, 3, 5-7, 10 Physicians should be aware of this rare adverse event, build an appropriate management strategy and encourage full vaccination. The patient in this manuscript has given written informed consent to the publication of his case details. None. None. The data used for this study are available from the corresponding author at reasonable request.