Dermatology Special Issue
This has been the week of the dermatologists: numerous studies reported on cutaneous manifestations seen in the context of COVID-19. The most prominent phenomenon, the so-called “COVID toes”, are chilblain-like lesions which mainly occur at acral areas [chilblain: Frostbeule (de), engelure (fr), sabañón (es), gelone (it), frieira (pt), 冻疮 (cn)]. These lesions can be painful (sometimes itchy, sometimes asymptomatic) and may represent the only symptom or late manifestations of SARS-CoV-2 infection. Of note, in most patients with “COVID toes”, the disease is only mild to moderate. It is speculated that the lesions are caused by inflammation in the walls of blood vessels, or by small micro clots in the blood. However, whether “COVID toes” represent a coagulation disorder or a hypersensitivity reaction is yet to be known. In addition, in many patients, SARS-CoV-2 PCR was negative (or not done) and serology tests (to proof the relationship) are still pending.
Fernandez-Nieto D, Jimenez-Cauhe J, Suarez-Valle A, et al. Characterization of acute acro-ischemic lesions in non-hospitalized patients: a case series of 132 patients during the COVID-19 outbreak. J Am Acad Dermatol. 2020 Apr 24. PubMed: https://pubmed.gov/32339703 . Full-text: https://doi.org/10.1016/j.jaad.2020.04.093
Authors describe two different patterns of acute acro-ischemic lesions, which can overlap. The chilblain-like pattern was present in 95 patients (72.0%). It is characterized by red to violet macules, plaques and nodules, usually at the distal aspects of toes and fingers. The erythema multiforme-like pattern was present in 37 patients (28.0%).
Galvan Casas C, Catala A, Carretero Hernandez G, et al. Classification of the cutaneous manifestations of COVID-19: a rapid prospective nationwide consensus study in Spain with 375 cases. Br J Dermatol. 2020 Apr 29. PubMed: https://pubmed.gov/32348545 . Full-text: https://doi.org/10.1111/bjd.19163
Authors describe five clinical cutaneous of lesions: acral areas of erythema with vesicles or pustules (pseudo-chilblain) (19%), other vesicular eruptions (9%), urticarial lesions (19%), maculopapular eruptions (47%) and livedo or necrosis (6%). Vesicular eruptions appear early in the course of the disease (15% before other symptoms). The pseudo-chilblain pattern frequently appears late in the evolution of the COVID-19 disease (59% after other symptoms).
Piccolo V, Neri I, Filippeschi C, et al. Chilblain-like lesions during COVID-19 epidemic: a preliminary study on 63 patients. J Eur Acad Dermatol Venereol. 2020 Apr 24. PubMed: https://pubmed.gov/32330334 . Full-text: https://doi.org/10.1111/jdv.16526
Preliminary results of a survey among Italian dermatologists and paediatrics, reporting on 63 cases (only a few patients with confirmed COVID-19).
Recalcati S, Barbagallo T, Frasin LA, et al. Acral cutaneous lesions in the Time of COVID-19. J Eur Acad Dermatol Venereol. 2020 Apr 24. PubMed: https://pubmed.gov/32330324 . Full-text: https://doi.org/10.1111/jdv.16533
A Dermatology Unit in Italy reports on 14 cases including 11 children. Lesions were localized on the feet in 8 cases, on the hands in 4 cases, on both sites in 2.
Duong TA, Velter C, Rybojad M, et al. Did Whatsapp reveal a new cutaneous COVID-19 manifestation? J Eur Acad Dermatol Venereol. 2020 Apr 24. PubMed: https://pubmed.gov/32330322 . Full-text: https://doi.org/10.1111/jdv.16534
In a Whatsapp group of 400 French dermatologists, a total of 295 atypical skin eruptions or lesions of suspected or confirmed COVID-19 patients were posted between March 14 and April 10. Chilblains or chilblain-like lesions represented 146 posts, and 149 posts included other suspected COVID19-related skin eruption e.g. urticaria, rash, chickenpox-like or pytiriasis rosea.
Marzano AV, Genovese G, Fabbrocini G, et al. Varicella-like exanthem as a specific COVID-19-associated skin manifestation: multicenter case series of 22 patients. J Am Acad Dermatol. 2020 Apr 16. PubMed: https://pubmed.gov/32305439 . Full-text: https://doi.org/10.1016/j.jaad.2020.04.044
Case series on 22 adult patients with varicella-like lesions. Typical features were constant trunk involvement, usually scattered distribution and mild/absent pruritus, the latter being in line with most viral exanthems but unlike true varicella. Lesions generally appeared 3 days after systemic symptoms and disappeared upon 8 days.
Sanchez A, Sohier P, Benghanem S, et al. Digitate Papulosquamous Eruption Associated With Severe Acute Respiratory Syndrome Coronavirus 2 Infection. JAMA Dermatol. 2020 Apr 30. PubMed: https://pubmed.gov/32352486 . Full-text: https://doi.org/10.1001/jamadermatol.2020.1704
Case report on digitate papulosquamous eruption in a patient with severe COVID-19. This paraviral dermatosis could be a secondary result of the immune response against the virus.
Diaz-Guimaraens B, Dominguez-Santas M, Suarez-Valle A, et al. Petechial Skin Rash Associated With Severe Acute Respiratory Syndrome Coronavirus 2 Infection. JAMA Dermatol. 2020 Apr 30. PubMed: https://pubmed.gov/32352487 . Full-text: https://doi.org/10.1001/jamadermatol.2020.1741
And yes, of course, rash may also occur. Case report with petechial skin rash with striking absence of lesions in the crural folds.
Quintana-Castanedo L, Feito-Rodriguez M, Valero-Lopez I, Chiloeches-Fernandez C, Sendagorta-Cudos E, Herranz-Pinto P. Urticarial exanthem as early diagnostic clue for COVID-19 infection. JAAD Case Rep. 2020 Apr 29. PubMed: https://pubmed.gov/32352022 . Full-text: https://doi.org/10.1016/j.jdcr.2020.04.026
Another patient with impressive rash (a 61-year-old Spanish Medical Doctor).
Madigan LM, Micheletti RG, Shinkai K. How Dermatologists Can Learn and Contribute at the Leading Edge of the COVID-19 Global Pandemic. JAMA Dermatol. 2020 Apr 30. PubMed: https://pubmed.gov/32352485 . Full-text: https://doi.org/10.1001/jamadermatol.2020.1438
A word of caution. Not all rashes or cutaneous manifestations seen in patients with COVID-19 can be attributed to the virus. Coinfections or medical complications have to be considered. Comprehensive mucocutaneous examinations, analysis of other systemic clinical features or host characteristics, and histopathologic correlation, will be vital to understanding the pathophysiologic mechanisms of what we are seeing on the skin.