Response to 'Classification of the cutaneous manifestations of COVID-19: a rapid prospective nationwide consensus study in Spain with 375 cases': vesicular eruption in COVID-19 - to exclude varicella.

dear editor, We read with interest the classification of cutaneous manifestations in COVID‐19 by Galván Casas et al. In particular, vesicular eruptions are characterized as monomorphic vesicles, involving the trunk, happening early in the course of the disease, and occasionally preceding other symptoms. , , However, investigations to exclude other causes of widespread vesicular eruption, in particular varicella, were absent.

In our clinical experience to date, we have had four patients with SARS‐CoV‐2 infection presenting with vesicular eruptions, which were subsequently confirmed to be true varicella with microbiological and serological investigations (Table 1). All four patients were young to middle‐aged men with no previous history of varicella infection, vaccination or exposure, presenting with vesicular eruptions of variable durations. Each patient had some features not completely typical of varicella – two described no or mild pruritus, two did not report any prodromal symptoms, and two presented with monomorphic vesicular eruptions early in the course of varicella infection. They were all given systemic antiviral therapy with aciclovir or valaciclovir, with resolution.

Table 1

Demographic and clinical data of patients with concomitant varicella and COVID‐19 infection

Patient	1	2	3	4
Sex	Male	Male	Male	Male
Age (years)	28	33	32	43
Skin lesions	Diffuse monomorphic vesicular lesions	Diffuse monomorphic vesicular lesions	Diffuse papulovesicular lesions	Diffuse vesicular lesions
Skin symptoms	Itching	Mild itching	Itching	No itching
Localization	Head, neck, trunk	Neck, trunk	Head, trunk	Head, trunk
Time to onset of skin lesions from SARS‐CoV‐2 infection (days)	18	21	17	19
Systemic symptoms	Fever, headache	Fever, headache, myalgia	None	None
History of varicella infection or vaccination	None	None	None	None
History of varicella exposure	None	None	None	None
Investigation results	VZV PCR positive	VZV PCR positive	VZV IgG positive	VZV IgG positive
Treatment	Oral aciclovir	Oral valaciclovir	Oral valaciclovir	Oral valaciclovir
Course	Resolution	Resolution	Resolution	Resolution

PCR, polymerase chain reaction; VZV, varicella zoster virus.

In a patient presenting with a widespread vesicular eruption, differential diagnoses include infections, a drug‐induced blistering process, and an autoimmune blistering disease. Among the infections, varicella, disseminated zoster, disseminated herpes, smallpox and rickettsialpox are possible causes.

Our experience with concomitant SARS‐CoV‐2 and varicella infection highlights the importance of excluding true varicella before ascribing vesicular eruptions to COVID‐19. Atypical features may be present, especially in early or recurrent varicella. Moreover, we have also previously reported coinfection of varicella with another viral infection (herpes simplex virus) in an immunocompetent host. Hence, it is possible that cases of vesicular eruptions in COVID‐19 may be arising from varicella infection.

As an accurate diagnosis of varicella has far‐reaching clinical implications on the treatment, patient disposition and postexposure prophylaxis for contacts, varicella infection should be excluded in patients with COVID‐19 presenting with vesicular eruptions.