A clinicopathological description of COVID-19-induced chilblains (COVID-toes) correlated with a published literature review

Athanassios Kolivras, Curtis Thompson, Ievgenia Pastushenko, Marisa Mathieu, Pascal Bruderer, Marine de Vicq, Francesco Feoli, Saadia Harag, Isabelle Meiers, Catherine Olemans, Ursula Sass, Florence Dehavay, Ali Fakih, Xuan-Lan Lam-Hoai, Alice Marneffe, Laura Van De Borne, Valerie Vandersleyen, Bertrand Richert

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11 Citations (Scopus)


Background The abundance of publications of COVID-19-induced chilblains has resulted in a confusing situation. Methods This is a prospective single-institution study from 15 March to 13 May 2020. Thirty-two patients received PCR nasopharyngeal swabs. Of these, 28 patients had a thoracic CT-scan, 31 patients had blood and urine examinations, 24 patients had skin biopsies including immunohistochemical and direct immunofluorescence studies, and four patients had electron microscopy. Results COVID-19-induced chilblains are clinically and histopathologically identical to chilblains from other causes. Although intravascular thrombi are sometimes observed, no patient had a systemic coagulopathy or severe clinical course. The exhaustive clinical, radiological, and laboratory work-up in this study ruled-out other primary and secondary causes. Electron microscopy revealed rare, probable viral particles whose core and spikes measured from 120 to 133 nm within endothelium and eccrine glands in two cases. Conclusion This study provides further clinicopathologic evidence of COVID-19-related chilblains. Negative PCR and antibody tests do not rule-out infection. Chilblains represent a good prognosis, occurring later in the disease course. No systemic coagulopathy was identified in any patient. Patients presenting with acral lesions should be isolated, and chilblains should be distinguished from thrombotic lesions (livedo racemosa, retiform purpura, or ischemic acral necrosis).
Original languageEnglish
Pages (from-to)17-28
Number of pages12
JournalJournal of cutaneous pathology
Issue number1
Publication statusPublished - Jan 2022


  • chilblains
  • coagulation
  • coagulopathy
  • COVID-19
  • COVID-toes
  • CT-scan
  • direct immunofluorescence study
  • electron microscopy
  • histopathology
  • hypercoagulable
  • immunohistochemistry
  • interferon
  • livedo racemosa
  • lupus erythematosus
  • paraviral
  • retiform purpura
  • severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)
  • thrombi

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