Cutaneous purpura following CoViD-19 vaccination

ABSTRACT

Case report A 67-year-old male presented to our hospital with a sudden eruption of pruritic, erythematous-to-violaceous purpura and plaques distributed along the lower and upper extremities and low back. Ten days prior he was vaccinated with Vaxzevria. No systemic involvement or manifestation was perceived. He had no prior history of allergy or purpuric skin eruption and had not recently started any new medication. Laboratory tests (included autoimmunity screening) and instrumental examinations were normal, except for a mild pericardial effusion. Biopsies obtained from the left arm both showed a picture compatible with leucocytoclastic vasculitis. After discussing risks and benefits the patient was discharged with topical steroids and a prednisone taper. Discussion: Vasculitis exacerbation has been reported secondary to multiple vaccines. However, this relationship is rare and it has yet to be determined. A possible mechanism might be vessel damage likely secondary to abnormal immunological activation with vaccine-related antigens promoting antibody development and immune complex deposition. Despite systemic steroids cause variable effects on immunity, up to 20 mg/day of prednisone seems to not have any effect on patients' immune response to vaccines. For the CoViD-19 vaccine, it is speculated that regardless of the type of vaccine, systemic corticosteroids have no or minimal risk in patients' immune response. Conclusions: It is important for healthcare providers to be aware that the CoViD-19 vaccine can potentially precipitate or exacerbate cutaneous inflammation.