Dear Editor, A 42‐year‐old man developed nonpainful erythematous‐to‐purplish patches located on his distal phalanges and nail beds (Figure) after the first dose of the anti‐COVID‐19 vaccine (+ 12 days, Pfizer‐BioNTech COVID‐19, BNT162b2) along with an acrocyanosis of the hands. Although negative antibodies do not preclude a previous exposure to the virus, blood and swab tests were negative for COVID‐19 infection and thrombophilic/autoimmune conditions. After the second jab (+ 21 days) no worsening of the lesions or other onset of symptoms were observed. A diagnosis of possible severe adverse event due to vaccine administration was made.1 Chilblain lesions have been described in patients with COVID‐19 and may be due to an abnormal inflammatory response. Although not reported in clinical trials,2 vaccination may have promoted an immunological reaction leading to vascular swelling and perniosis similar to what has been observed after COVID‐19 infection.

Author Contribution
Alessandro Pileri: Conceptualization (equal); Data curation (equal); Formal analysis (equal); Investigation (equal); Writing‐original draft (equal); Writing‐review & editing (equal). Alba Guglielmo: Conceptualization (equal); Data curation (equal); Formal analysis (equal); Visualization (equal); Writing‐original draft (equal); Writing‐review & editing (equal). Beatrice Raone: Formal analysis (equal); Investigation (equal); Validation (equal); Visualization (equal). Annalisa Patrizi: Conceptualization (equal); Data curation (equal); Supervision (equal); Validation (equal).
Contributor Information
A. Pileri, Dermatology‐IRCCS Policlinico di Sant’Orsola Department of Experimental, Diagnostic and Specialty Medicine Alma Mater Studiorum University of Bologna Italy Dermatology Unit Department of Experimental, Diagnostic and Specialty Medicine University of Bologna Italy.
A. Guglielmo, Dermatology‐IRCCS Policlinico di Sant’Orsola Department of Experimental, Diagnostic and Specialty Medicine Alma Mater Studiorum University of Bologna Italy Dermatology Unit Department of Experimental, Diagnostic and Specialty Medicine University of Bologna Italy.
B. Raone, Dermatology‐IRCCS Policlinico di Sant’Orsola Department of Experimental, Diagnostic and Specialty Medicine Alma Mater Studiorum University of Bologna Italy
A. Patrizi, Dermatology‐IRCCS Policlinico di Sant’Orsola Department of Experimental, Diagnostic and Specialty Medicine Alma Mater Studiorum University of Bologna Italy Dermatology Unit Department of Experimental, Diagnostic and Specialty Medicine University of Bologna Italy.
References
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- Polack FP, Thomas SJ, Kitchin N et al. Safety and efficacy of the BNT162b2 mRNA Covid‐19 vaccine. N Engl J Med 2020; 383:2603–15. [DOI] [PMC free article] [PubMed] [Google Scholar]
