Covid-19-induced skin rashes: which ones healthcare professionals might encounter
Although COVID-19 represents a highly infectious respiratory virus, in the first publication describing the clinical signs among a group of 1099 people from Wuhan, China, only 0.2% of patients1 were reported to have cutaneous symptoms but no details were provided. As case numbers rose across the world, dermatologists and other specialists were deployed to the front-line and the first detailed account of the cutaneous signs of COVID-19, were reported by a group of Italian dermatologists, who found that in a sample of 88 patients, 20.4% (18) developed skin manifestations.2
In June 2020, self-reported symptoms collected as part of the COVID symptom study by a team from Kings’ College London, led researchers to propose that skin rashes3 be considered as a fourth key sign of COVID-19 infection. Interestingly, data published4 from the group, which included over 330,000 people, found that 17% who tested positive for COVID-19, described a skin rash as the first symptom of infection. Furthermore, 21% of those who stated that they developed a rash, were later confirmed to be infected with COVID-19.
As skin rashes might be a sign of COVID-19, what should healthcare professionals look out for? Many articles have described skin changes in those with COVID-19 and the most common rashes that have been reported include:
Commonly affecting the trunk or limbs but sometimes the face in around 20% of cases. Furthermore, one case study reported a patient initially presenting with odynophagia (difficulty swallowing) and an urticarial rash5 on the hands and face before the onset of other COVID-19 symptoms.
This most commonly affects acral surfaces such as the toes and has become known as COVID toes and resembles chilblains. Interestingly, dermatologists felt that pseudo-chilblains were most likely to be caused by COVID-19 since chilblains are more common in colder weather and in those with poor circulation yet these lesions were occurring in warmer weather and often seen in younger people. The condition can be asymptomatic but reported symptoms have included itchiness and tenderness and sometimes occurring after oedema.
An erythemato-papular rash6 (i.e., a red bumpy rash) or erythemato-vesicular7 (chicken-pox like) consisting of small and pruritic blisters has been identified in several reports. The rash itself can be localised or even generalised to the whole body and it seems that patients develop the rash at the onset of symptoms and the rash can take up to 10 days to resolve.
These are purple coloured rashes caused by blood leaking into the skin and have also been reported in patients with COVID-19.
Lesions occurring in the mouth, eyes and genitals have also been described. Although many of the above rashes can be due to different conditions, e.g., urticarias can be caused by an adverse drug reaction, healthcare professionals should always enquire about any other symptoms to try and rule out an infected individual. As discussed above, the most likely skin changes due to COVID-19 are pseudo-chilblains.
About the author
Rod Tucker is a pharmacist with over 30 years’ experience and is currently an independent researcher and writer focusing on dermatology.
1 Wei-Jie G et al. Clinical Characteristics of Coronavirus Disease 2019 in China. N Engl J Med 2020 Apr 30;382(18):1708-1720. doi: 10.1056/NEJMoa2002032. Epub 2020 Feb 28. Accessible at: https://pubmed.ncbi.nlm.nih.gov/32109013/ Last accessed: 30th Nov 2020
2 S. Recalcati et al. Cutaneous manifestations in COVID‐19: a first perspective. Journal of the European Academy of Dermatology and Venereology. 26 March 2020. Accessible at: ttps://doi.org/10.1111/jdv.16387 Last accessed: 30th Nov 2020
3 COVID Symptom Study. Skin rash should be considered as a fourth key sign of COVID-19. September 14 2020. Accessible at: https://covid.joinzoe.com/us-post/skin-rash-covid Last accessed: 30th Nov 2020
4 Visconti A et al. Diagnostic value of cutaneous manifestation of SARS-CoV-2 infection. medRxiv. Oct 26 2020. Accessible at: https://doi.org/10.1101/2020.07.10.20150656 Last accessed: 30th Nov 2020
5 D. Henry et al. Urticarial eruption in COVID‐19 infection. Journal of the European Academy of Dermatology and Venereology. 15 April 2020. Accessible at: https://doi.org/10.1111/jdv.16472 Last accessed: 30th Nov 2020
6 COVID-19 images. DermNet NZ. Accessible at: https://dermnetnz.org/topics/covid-19-images/ Last accessed: 30th Nov 2020
7 Bosworth T. COVID-19 Skin Manifestation Heterogeneity. MedicineNet. 6 May 2020. Accessible at: https://www.medicinenet.com/covid-19_skin_manifestation_heterogeneity-news.htm Last accessed: 30th Nov 2020