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.