The story of COVID-19 and skin manifestations is changing every day, with dozens of papers still in press. While the spotlight has fallen on pseudo-chilblains ("COVID toes"), the pathophysiology behind this strange manifestation remains mysterious. Some question whether this is a true COVID manifestation or merely an epiphenomenon—so-called "quarantine toes"—brought about by more people walking barefoot during quarantine and an unusually cold spring in parts of the United States.
Some cases may indeed be idiopathic pernio, which is more likely to be reported due to detection bias, given the large amount of recent media coverage about this finding.
Neither detection bias nor a cold spring in the United States can explain the fact that cases are occurring in warm climates in individuals with positive SARS-CoV-2 viral swabs or serologies. A second unrelated infectious trigger causing a surge in pernio, while possible, seems far-fetched.
COVID-associated pernio is treated with the same drugs used for idiopathic pernio. These include high-potency corticosteroids, aspirin, topical calcium channel blockers such as nifedipine, and nitroglycerin paste. All of these uses are off-label.
Decisions in patients with COVID-related skin manifestations plus other characteristic symptoms (eg, cough, fever, shortness of breath, anosmia, loss of taste) or known COVID exposure are easy. They should be tested via nasopharyngeal swab and serologies.
In contrast, those with suspicious skin manifestations who are otherwise asymptomatic, especially with no other risk factors, fall into a gray area. Should such individuals be tested? Should they self-quarantine? To date, there is no clear consensus.
Thanks to coordinated efforts such as the nationwide consensus study in Spain and the American Academy of Dermatology's COVID-19 Dermatology Registry, we can anticipate a better understanding of how and why SARS-CoV-2 affects the skin. Hopefully, these insights will shed light on why this pathogen is so deadly for some and yet mild or asymptomatic in others.
Graeme M. Lipper, MD, is a clinical assistant professor at the University of Vermont Medical College in Burlington, Vermont, and a partner at Advanced DermCare in Danbury, Connecticut.
Medscape Dermatology © 2020 WebMD, LLC
Any views expressed above are the author's own and do not necessarily reflect the views of WebMD or Medscape.
Cite this: Graeme M. Lipper. 'COVID Toes' and 'Kawasaki' Rash: 5 Cutaneous Signs in COVID-19 - Medscape - May 08, 2020.