Skin amidst COVID-19 pandemic.

Dear Editor,

Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) causing coronavirus disease 2019 (COVID‐19) was first reported in Wuhan, China in December 2019. By February 15, it had rapidly spread throughout China and across the world including India. It was termed as a pandemic condition by March 11 by the World Health Organization.

There are few reports of cutaneous manifestations of coronavirus in the English literature and the data on this novel variety are scarce. Recalcati studied dermatological manifestations of COVID‐19 in 88 patients affected with this virus and found cutaneous involvement in 18 (20.4%) patients. Eight of these patients developed these manifestations at the disease onset, while 10 patients developed them after the hospitalization. The morphological patterns noted include maculopapular rash, urticarial wheals, and varicelliform eruptions. The trunk was the commonest involved site. There was minimal to no itching and the lesions resolved in few days. Moreover, there was no correlation with the disease severity.

In a retrospective analysis of seven critically ill COVID‐19 patients with pneumonia in Wuhan, China, it was found that all of them had different degrees of limb ischemia, which manifested as cyanosis, blisters filled with blood, and dry gangrene. Four of them met the diagnostic criteria for disseminated intravascular coagulation (DIC) suggesting a high risk of hypercoagulation in such patients which mandates timely attention. Petechial rash mimicking dengue was described in a patient with COVID‐19 where an initial diagnosis of dengue was considered due to the nature of the rash and associated thrombocytopenia. Various other cutaneous manifestations reported recently in COVID‐19 patients including maculopapular skin lesions, associated Kawasaki disease, pseudochilblain (also referred to as “COVID toes”) livedo‐like lesions, , urticarial or Purpuric skin lesions, and so on are mentioned in Table 1. These reports suggest that vasculitis of small blood vessels, embolic occlusion of the vessels, and resulting ischemia could be the pathogenic mechanisms for these cutaneous manifestations in addition to abnormal immunological response. Galván Casas et al found that vesicular lesions appeared early in the course of the disease while pseudochilblain appeared late. Both types of lesions were reported to be specific to COVID‐19. Skin lesions were reported as the presenting manifestation in many of these patients in absence of fever and respiratory complaints. , Chilblain‐like lesions were associated with a good prognosis, while limb ischemia was associated with a poor prognosis. The possible proposed pathogenic mechanisms and skin histopathology findings are mentioned in few studies as tabulated in Table 1.

TABLE 1

Reported cutaneous manifestations of novel corona virus (SARS‐CoV‐2)

S. No.	References	Cutaneous manifestations	Number of patients	COVID (corona virus disease) status	Mechanism	Histopathology
1	Galván Casas et al 1	Maculopapular (47%) Pseudochilblain (19%) Urticarial (19%) Vesicular (9%) Livedo/necrosis (6%)	375	Suspected/+ve	Polymorphism in presentation due to alternative causes, or differences in the virus or the host Role of coinfection with other viruses like herpes	‐
2	Recalcati 2	Erythematous rash Urticaria Varicelliform eruptions	14 3 1	+ve	‐	‐
3	Zhang et al 3	Cyanosis, blood‐filled vesicles, dry gangrene	7	+ve	Hypercoagulation, DIC	‐
4	Joob et al 4	Petechial rash	1	+ve	‐	‐
5	Jones et al 5	Kawasaki disease	1	+ve	SARS‐CoV‐2 as the causative virus	‐
6	Ahouach et al 6	Diffuse fixed erythematous blanching maculopapules Burning sensation over palms	1	+ve	Immune reaction to the virus	Spongiosis, basal cell vacuolation and mild perivascular lymphocytic infiltrate
7	Bouaziz et al 7	Exanthema Varicelliform Urticaria Violaceous macules with “porcelain‐like” appearance Livedo Non‐necrotic Purpura Necrotic purpura Chilblain Chilblain appearance with Raynaud's phenomenon Eruptive cherry angioma	4 2 1 1 1 1 1 1 1 1	+ve	Immune dysregulation, vasculitis Vessel thrombosis/neoangiogenesis	‐

Abbreviations: DIC, disseminated intravascular coagulation; SARS‐CoV‐2, severe acute respiratory syndrome coronavirus 2.

In relation to preexisting dermatoses, patients suffering with autoimmune diseases like systemic lupus erythematosus, systemic sclerosis, and mixed connective tissue disease require a special attention as there may be a flare of rheumatologic manifestations in these patients with COVID‐19. There can be a false‐positive coronavirus antibody test in samples collected from these patients, which should be taken into consideration while interpretation of antibody test for this virus. Systemic inflammatory response is a proposed pathogenic mechanism in children with COVID‐19, and Kawasaki disease that has been provisionally referred as pediatric inflammatory multisystem syndrome temporally associated with SARS‐CoV‐2. In an interesting observation, Goren et al hypothesized that males with androgenetic alopecia (AGA) are more likely to suffer from COVID‐19 complications compared to controls probably due to involvement of TMPRSS2 gene in both AGA and corona virus attachment to pneumocytes. Hence, if this role is confirmed in future, antiandrogens can be used as anticorona therapy.

Thus, there are emerging data regarding the cutaneous manifestations related to COVID‐19 and its knowledge is important as it may provide a clue to the pathogenesis of the disease and may also serve as a prognostic marker.

CONFLICT OF INTEREST

The authors declare no potential conflict of interest.