Discussion:
Cases of BP related to vaccine administration have been reported mainly in children, including influenza, varicella zoster, tetanus, hepatitis B, human papilloma virus and recently COVID-19 vaccines.2,3To our knowledge, BP induced by Covid 19 vaccines are most commonly related to mRNA vaccines.3 In our patient, itching followed the first injection of Pfizer BioNTech and blisters secondary appeared in the same areas. It could also happen after the second dose in some other cases.3,4 Trunk and extremities were the most affected sites.3Vaccine–associated BP disease may differ from conventional BP in some individuals. Atypical target lesions and acral distribution seen in our patient had not been described yet. That raised the differential diagnosis of erythema multiforme. One case of a patient who developed maculo-papular and acral vesicular rashes evolving into BP was associated to prolonged Covid19 infection. 5 Our patient showed full cutaneous recovery with no clinical relapse after two months of follow up. In all cases, resolution within a few weeks was obtained. 3,4 This could imply that BP induced by covid 19 vaccine may have atypical presentations and displays a good response to treatment with a better prognosis than conventional BP. Thus, it should not contribute to unnecessary avoidance of future vaccination doses.