First Onset of Pityriasis Rubra Pilaris following SARS-CoV-2 Booster Vaccination: Case Report and Review of the Literature

There is increasing evidence of adverse events associated with the use of COVID-19 vaccines. Here, we report a case of the SARS-CoV-2-vaccination-related onset of pityriasis rubra pilaris (PRP) and provide an analysis of previously reported cases in the medical literature. A 67-year-old male presented with a 1-year history of histopathologically proven PRP that first developed 14 days after receiving a COVID-19 booster vaccination. Skin symptoms improved under ustekinumab medication after unsuccessful previous treatment approaches using systemic corticosteroids, brodalumab, and risankizumab. Among the published cases of post-COVID vaccination PRP, 12 (75%) males and 4 (25%) females were reported. The median age of the reported patients was 59 years. In 10 out of 16 patients (62.5%), PRP was diagnosed after the first vaccine dose, in 4 (25%) after the second dose, and in 2 of 15 patients (12.5%) after the third dose. The median time between COVID-19 vaccination and the onset of PRP was 9.5 days (range: 3–60 days). The majority of patients required systemic treatment, including systemic retinoids and methotrexate. PRP might be a rare adverse event after COVID-19 vaccination, particularly affecting older males. Even though most reported patients with COVID-19-vaccination-related PRP could be successfully treated with PRP standard medications, therapy refractory cases may also occur. Thus, clinicians must be aware of this rare but potentially severe complication