Pityriasis rubra pilaris (type I) following ChAdOx1 COVID‐19 vaccine: report of two cases with successful treatment with oral isotretinoin

Pityriasis following COVID-19 vaccinations: a systematic review

In the wake of a global COVID-19 pandemic, where innovations in vaccination technology and the speed of development and distribution have been unprecedented, a wide variety of post-vaccination cutaneous reactions have surfaced. However, there has not been a systematic review that investigates pityriasis eruptions and the associated variants following COVID-19 inoculations. A PubMed search using Preferred Reporting Items for Systematic Reviews and Meta-Analyses was performed to find case reports from the earliest record through November 2022. Data including types of vaccination and pityriasis were extracted and a quality review was performed; 47 reports with 94 patients were found: 64.9% had pityriasis rosea (PR), 3.2% PR-like eruptions, 16.0% pityriasis rubra pilaris, 7.4% pityriasis lichenoides et varioliformis acuta, 3.2% pityriasis lichenoides chronica, and 5.3% had reactions described as atypical. The top three COVID-19 vaccinations reported were Pfizer-BioNTech (47.9%), Oxford-AstraZeneca (11.7%), and Moderna (8.5%). Pityriasis reactivity was reported most frequently after the Pfizer-BioNTech vaccination, with pityriasis rosea being the most common variant. A large difference was additionally found between the ratio of post-vaccination pityriasis reactions following Pfizer and Moderna vaccinations (5.63), and the ratio of Pfizer's usage in the United States as of December 28, 2022 relative to that of Moderna (1.59). Further studies with adequate follow-up periods and diagnostic testing will thus need to be performed to elucidate the root of this discrepancy and better characterize the association between different pityriasis reactions and COVID-19 vaccinations.

Pityriasis Rubra Pilaris: An Updated Review of Clinical Presentation, Etiopathogenesis, and Treatment Options

Pityriasis rubra pilaris (PRP) is a rare papulosquamous reaction pattern with a significant impact on quality of life. Type I PRP is the most common PRP variant, presenting as erythematous papules emerging in a follicular distribution and later coalescing into plaques with characteristic islands of sparing; histologically, an alternating pattern of orthokeratosis and parakeratosis is considered the hallmark of PRP (checkerboard hyperkeratosis). Other PRP variants (types II-V) differ in their age of onset and clinical presentation. Type VI PRP is a rare PRP subtype associated with human immunodeficiency virus infection and is occasionally associated with diseases of the follicular occlusion tetrad. Caspase recruitment domain family, member 14 (CARD14)-associated papulosquamous eruption and facial discoid dermatitis are newly described disease states that have an important clinical overlap with PRP, creating shared conundrums with respect to diagnosis and treatment. The etiology inciting PRP often remains uncertain; PRP has been suggested to be associated with infection, malignancy, or drug/vaccine administration in some cases, although these are based on case reports and causality has not been established. Type V PRP is often due to inborn CARD14 mutations. Furthermore, recent literature has identified interleukin-23/T-helper-17 cell axis dysregulation to be a major mediator of PRP pathogenesis, paving the way for mechanism-directed therapy. At present, high-dose isotretinoin, ixekizumab, and secukinumab are systemic agents supported by single-arm prospective studies; numerous other agents have also been trialed for PRP, with variable success rates. Here, we discuss updates on clinical manifestations, present new insights into etiopathogenesis, and offer a survey of recently described therapeutic options.

Oral Isotretinoin and Its Uses in Dermatology: A Review

In 1982, the Food and Drug Administration (FDA) of the United States of America approved isotretinoin (13-cis-retinoic acid), a retinoid derivative of vitamin A, to treat severe recalcitrant acne vulgaris. Apart from its prescribed use for severe acne, evidence suggests that isotretinoin is commonly used off-label to treat mild-to-moderate acne, inflammatory skin conditions, genodermatoses, skin cancer, and other skin disorders. This is due to its anti-inflammatory, immunomodulatory, and antineoplastic properties. Some "off-label" use is successful, while others are ineffective. Therefore, this information is essential to clinicians for deciding on the appropriate use of isotretinoin. In this article, we aim to review the most updated evidence-based data about the use of oral isotretinoin in dermatology.

Pityriasis Rubra Pilaris After Moderna COVID-19 Vaccination: A Case Report and Literature Review

ABSTRACT

To date, over 60% of the world's population has received at least 1 dose of coronavirus disease 2019 (COVID-19) vaccination, with over 12 billion doses administered globally. Commonly reported adverse effects of COVID-19 vaccination include fever, headache, myalgia, and injection site reactions. The spectrum of documented cutaneous reactions after COVID-19 vaccination is broad; however, pityriasis rubra pilaris (PRP) or PRP-like eruption secondary to COVID-19 vaccine is exceedingly rare, with only 17 cases previously reported to date in the English literature. In this article, we describe an additional case of COVID-19 vaccination-associated PRP in a 50-year-old woman with a history of metastatic breast carcinoma, who developed a widespread cutaneous eruption characteristic of PRP, including palmoplantar keratoderma, 10 days after her third dose of Moderna COVID-19 vaccine. Punch biopsy specimen showed epidermal hyperplasia with overlying hyperkeratosis, alternating orthokeratosis and parakeratosis and focal follicular plugging, supporting the diagnosis of PRP. The patient improved within weeks of initiating oral acitretin and topical steroids, with resolution achieved after 3 months of continued therapy. To the best of our knowledge, this is the third reported case of Moderna COVID-19 vaccination-associated PRP and collectively the 18 th after the administration of all COVID-19 vaccines currently available, including Pfizer-BioNTech, and AstraZeneca.

Ixekizumab successfully treated severe pityriasis rubra pilaris after COVID-19 vaccination

Pityriasis rubra pilaris is an inflammatory dermatologic disorder of unknown cause. We report a 67-year-old man with Pityriasis rubra pilaris might induced by COVID-19 vaccination. The patient developed the lesions after the first dose of vaccine and significantly aggravated after the second dose. He had poor effect and liver function impairment developed after acitretin used, but achieved satisfactory efficacy after replacement to ixekizumab, an interleukin-17A inhibitor.