COVID nails

Ivan Bristow PhD
On behalf of the COVID-19 Committee, College of Podiatry, London
3 November 2020

COVID toes - now be on the lookout for COVID nails

Over the last few months, during the global pandemic, we saw a rise in publications reporting the effects of the infection on the skin. Initially, under-reported it became evident that COVID-19 had the potential to cause a range of skin symptoms including erythema, urticaria, livedo reticularis, petechiae and chilblain-like lesions (1-5). It was the latter, of course, that became the focus of the podiatrist’s attention as the developing evidence of its possible association with COVID-19 was initially difficult to prove. Latterly, as I covered in a recent blog (https://www.foot.expert/post/covidtoes2), tissue samples from chilblain lesions in children and young adults showed markers of SARS-COV-2 infection finally confirming the connection.

Since then, reports have continued to be published on this but most recently in the International Journal of Dermatology, a paper discusses the case of a 37-year-old woman who developed COVID-19 symptoms which coincided with unusual nail changes. The paper by Mendez-Flores et al., (6) describes how the patient lost her sense of smell and taste and developed the classic dry cough and fever associated with the infection. A nasal swab proved positive for COVID-19. Two days later she noticed a red-violet band or flare developing in her fingernails, just distal to the lunula. This lasted a week and then disappeared.

So, what could this mean? Effectively, this is a single case study suggesting an association and it concurs an earlier publication which reported a similar finding in the fingernails of a 60-year-old patient (7). In proving a link with COVID-19 there is still a long way to go. More cases would be needed to corroborate these early findings. Then, tissue samples would be needed to demonstrate the pathology and establish the presence of the infection. Of course, the main barrier is the fact a nail biopsy in this area risks permanent nail changes and so it would be unlikely this would happen, particularly considering the phenomenon is only transient with no lasting effect as far as we know at the moment. Only time will tell and subsequent papers reporting this may lead to further developments.

References

1. Almutairi N, Schwartz RA. COVID-19 with dermatologic manifestations and implications: An unfolding conundrum. Dermatol Ther. 2020;n/a(n/a):e13544.
2. Colonna C, Genovese G, Monzani NA, Picca M, Boggio F, Gianotti R, et al. Outbreak of chilblain-like acral lesions in children in the metropolitan area of Milan, Italy, during the COVID-19 pandemic. J Am Acad Dermatol. 2020;37(3):437-40.
3. De Giorgi V, Recalcati S, Jia Z, Chong W, Ding R, Deng Y, et al. Cutaneous manifestations related to coronavirus disease 2019 (COVID-19): A prospective study from China and Italy. J Am Acad Dermatol. 2020:S0190-9622(20)30941-5.
4. Freeman EE, McMahon DE, Lipoff JB, Rosenbach M, Kovarik C, Desai SR, et al. The spectrum of COVID-19-associated dermatologic manifestations: an international registry of 716 patients from 31 countries. J Am Acad Dermatol. 2020.
5. Zhao Q, Fang X, Pang Z, Zhang B, Liu H, Zhang F. COVID-19 and cutaneous manifestations: a systematic review. J Eur Acad Dermatol Venereol. 2020;n/a(n/a).
6. Méndez-Flores S, Zaladonis A, Valdes-Rodriguez R. COVID-19 and nail manifestation: be on the lookout for the red half-moon nail sign. Int J Dermatol. 2020;59(11):1414-.
7. Neri I, Guglielmo A, Virdi A, Gaspari V, Starace M, Piraccini BM. The red half-moon nail sign: a novel manifestation of coronavirus infection. J Eur Acad Dermatol Venereol. 2020;n/a(n/a).