In their important study on skin findings associated with SARS-CoV-2 infection, Tan et al1 performed a review of all published articles regarding skin manifestations associated with COVID-19 and evaluated them through a global lens. By casting a broad net and including the full array of published articles from around the world, the authors were able to explore the ways in which the reporting of COVID-19 skin findings varies geographically. Notably, they pointed out the discordance between morphological reports among countries. Some of these were unsurprising—pernio, a condition in which immunoglobulin A immunoreactivity may be modulated by temperature, was reported only rarely in Asia—however, many others remain to be better understood. Most importantly, it is not clear whether differences in the reported skin manifestations truly reflect differences in skin manifestations or whether we are simply seeing artifacts associated with differential reporting practices.
It is critical to appreciate that essentially all reports on skin findings associated with COVID-19 are biased; even the best and largest registry studies, such as those sponsored by the American Academy of Dermatology and the International League of Dermatological Societies,2 , 3 are subject to the vagaries of the whims of those choosing to report their data. As we continue to explore the skin manifestations due to vaccination, many questions persist. Despite the murkiness of the data, one thing remains clear—we need dermatologists to continue to engage in prosocial actions, such as registry reporting, to ensure that we have the highest quality data available for hypothesis generation and further research.
Conflicts of interest
None disclosed.
Footnotes
Funding sources: None.
IRB approval status: Not applicable.
Reprints not available from the author.
References
- 1.Tan S.W., Tam Y.C., Oh C.C. Skin manifestations of COVID-19: a worldwide review. JAAD Int. 2021;2:119–133. doi: 10.1016/j.jdin.2020.12.003. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Freeman E.E., McMahon D.E., Lipoff J.B. The spectrum of COVID-19-associated dermatologic manifestations: an international registry of 716 patients from 31 countries. J Am Acad Dermatol. 2020;83(4):1118–1129. doi: 10.1016/j.jaad.2020.06.1016. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.McMahon D.E., Gallman A.E., Hruza G.J. Long COVID in the skin: a registry analysis of COVID-19 dermatological duration. Lancet Infect Dis. 2021;21(3):313–314. doi: 10.1016/S1473-3099(20)30986-5. [DOI] [PMC free article] [PubMed] [Google Scholar]