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Key Clinical MessageAcute generalized exanthematous pustulosis (AGEP) is a self‐limited drug reaction. Hydroxychloroquine (HCQ) is an uncommon cause of AGEP with a prolonged recovery course; Thus, the physicians should take the possibility of this rare but severe event in their minds and try to diagnose correctly and better management.

Herpes Zoster caused by reactivation of latent Varicella–Zoster virus (VZV). The rare disseminated form of it occurred mainly in immunocompromised patients. We hereby present the first case of atypical disseminated herpes zoster in a 54‐year‐old woman admitted with serious COVID. In this case, disseminated herpes zoster developed by purpuric lesions mimicking vasculitis and cutaneous drug reaction. Hence, this case serves as a reminder for considering atypical presentations of cutaneous disorders in immunocompromised patients, especially those affected with severe COVID.

An 82-year-old female patient presented with a recent onset of painful skin lesions in unilateral distribution on the abdominal area following the lines of Blaschko; the initial diagnosis of Varicella-Zoster infection was made. However, because the individual lesions appeared as hyperkeratotic papules and were unresponsive to antiviral therapy, a skin biopsy was performed, which revealed hyperkeratosis, suprabasal acantholysis and dyskeratosis with corps ronds and grains, consistent with acantholytic dyskeratotic acanthoma. Since this entity has been associated with Darier disease, wholetranscriptome sequencing by RNA-Seq was performed on RNA isolated from a lesion and from adjacent normal appearing skin, and a recently developed bioinformatics pipeline that can identify both genomic sequence variants and the presence of any of 926 viruses was applied. Two pathogenic missense mutations in the ATP2A2 gene were identified in the lesional but not in normal appearing skin, and no evidence of Varicella-Zoster infection was obtained. These findings confirm the diagnosis of segmental Darier disease due to postzygotic mutations in the ATP2A2 gene, and attest to the power of a novel single-step application of RNA-Seq in providing correct diagnosis in this rare genodermatosis.

Acute generalized exanthematous pustulosis (AGEP) is an exanthematous condition, predominantly occurring as a result of drug reactions. We, hereby, present the first case of AGEP following treatment with remdesivir in a patient with COVID-19, without hydroxychloroquine use, which serves as a reminder to consider remdesivir as a possible causative agent when dealing with AGEP presentation in COVID patients.