key: cord-1028753-qqkz01vy
authors: Llamas‐Velasco, M.; Chicharro, P.; Rodríguez‐Jiménez, P.; Martos‐Cabrera, L.; De Argila, D.; Fernández‐Figueras, M.; Fraga, J.
title: Reply to “Clinical and histological characterization of vesicular COVID‐19 rashes: a prospective study in a tertiary care hospital”: Pseudoherpetic Grover disease seems to appear in patients with COVID‐19 infection
date: 2020-05-21
journal: Clin Exp Dermatol
DOI: 10.1111/ced.14305
sha: 94fbd4399c919c99f9186f9140e2fbf59fe8ff13
doc_id: 1028753
cord_uid: qqkz01vy

We have read with great interest the article by Fernandez‐Nieto et al. showing histopathological pictures of one of the two biopsied cases from their 24 patients diagnosed of vesicular lesions related to COVID‐19.(1) They additionally performed a real‐time PCR for SARS‐CoV‐2 that was negative in four tested cases.(1) Regarding their case histopathological pictures, we agree with their description as we can observe acantholytic cells, some of them with dyskeratotic features or grouped without a clear molding of nucleus but reminiscent of the multinucleated giant cells typically observed in herpetic lesions, a picture that looks to our eyes, most likely as an infrequent entity named pseudoherpetic Grover disease (GD),(2) first described as vesicular GD by Fernandez‐Figueras.(3)

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We have read with great interest the article by Fernandez-Nieto et al. showing histopathological pictures of one of the two biopsied cases from their 24 patients diagnosed of vesicular lesions related to COVID-19. 1 They additionally performed a real-time PCR for SARS-CoV-2 that was negative in four tested cases. 1 Regarding their case histopathological pictures, we agree with their description as we can observe acantholytic cells, some of them with dyskeratotic features or grouped without a clear molding of nucleus but reminiscent of the multinucleated giant cells typically observed in herpetic lesions, a picture that looks to our eyes, most likely as an infrequent entity named pseudoherpetic Grover disease (GD), 2 first described as vesicular GD by Fernandez-

Pseudoherpetic GD, clinically is characterized by asymptomatic or itchy papules, intermingled with crusts and isolated vesicles or pustules that mostly involve the trunk (Figure 1 ), a picture that overlaps with the diffuse pattern of vesicular lesions related to COVID-19, described by the authors. 1 Histopathologically, the main clues for the diagnosis of pseudoherpetic GD are the presence of intraepidermal vesicles, frequently filled with plasma; with scarce groups of acantholytic cells, mostly located in the lateral parts of the vesicle; while dermal inflammatory infiltrate, that may contain neutrophils can be also present ( Figure 2 ). In our series of pseudoherpetic GD we have not found viral inclusions and immunostaining for herpes virus and varicella were negative in all the cases. 2 COVID-19 infection characteristically produces lymphopenia, and immunosuppression is a predisposing factor for both, herpes virus recurrences 4 and pseudoherpetic GD. 2 As many patients can present during hospitalizations flare-ups or debuts of GD related to sweat in the context of fever, increased bedtime and immunosuppression, COVID-19 is likely to favor GD.

As we assume that tests to rule out a superimposed viral infection were done in all the published cases by Fernandez-Nieto et al, we would like to know if in that biopsied case, immunostainings for herpes simplex and zoster were negative, as we consider these immunostainings as mandatory to perform the diagnosis of pseudoherpetic GD, as true herpesvirus may superimpose on acantholytic diseases such as GD or others making the diagnosis more challenging. 5 The appearance of vesicles as a clinical presentation of GD raise the differential diagnosis with varicella or disseminated zoster and even with the vesicular lesions associated to COVID-19 as the clinical pattern of these entities may overlap.

In conclusion, we consider that when we face a patient with vesicular lesions even within the COVID-19 pandemic, Tzanck smear, PCR for Herpesviridae family on the vesicle fluid or skin Accepted Article

Clinical and histological characterization of vesicular covid-19 rashes: A prospective study in a tertiary care hospital

Clinico-pathological study of 4 cases of pseudoherpetic grover disease: The same as vesicular grover disease

Grover disease: A reappraisal of histopathological diagnostic criteria in 120 cases

Classification of the cutaneous manifestations of covid-19: A rapid prospective nationwide consensus study in spain with 375 cases

Hailey-hailey disease with coexistent herpes virus infection: Insights into the diagnostic conundrum of herpetic/pseudoherpetic features in cutaneous acantholytic disorders

This article is protected by copyright. All rights reserved Accepted Article