Pityriasis Rosea and Pityriasis Rosea-Like Eruption Following COVID-19 Vaccination: A Narrative Review

Herald Patch as the Only Evidence of Pityriasis Rosea: Clinical, Laboratory and Pathogenetic Features

Pityriasis rosea (PR) is a self-limited exanthem associated with the endogenous systemic reactivation of human herpesvirus (HHV)-6 and HHV-7. The disease typically begins with a single erythematous patch on the trunk (herald patch), followed by a secondary eruption of smaller papulosquamous lesions. Rarely, the herald patch may be the only cutaneous manifestation of PR. The present work aimed to examine the clinical and laboratory features of the PR cases characterized by the herald patch as the sole cutaneous manifestation and to compare them with the classic form of PR. An observational, retrospective study was conducted on patients presenting with herald patch as the only sign of PR (cases) and on a series of age- and sex-matched patients who presented with a typical PR pattern (controls). The records of the patients were extracted from a PR registry, which collected data on patients with PR diagnosed from 2003 to 2023 by at least two dermatologists from the same study team. Nineteen patients (eleven males, eight females) with a mean age of 27.1 years presented the herald patch as the only cutaneous manifestation of PR. Nineteen age- and sex-matched patients were considered controls. In the cases, the exanthem duration was shorter than in controls, and the mean HHV-6 and HHV-7 DNA plasma load was lower than in controls. This rare variant of PR might be considered an abortive form of the exanthem that occurs when the HHV-6/7 reactivation from latency is contrasted by a more robust immunological response than in classic PR.

A Case of Persistent Pityriasis Rosea Successfully Treated by a Short Course of Therapy with Abrocitinib

Pityriasis rosea (PR) is a common inflammatory, erythematous and scaly skin condition that usually affects individuals aged from 20 to 40 years old. The disease often exhibits a self-limiting course up to 6-8 weeks. We report a 25-year-old female patient with a six-month history of red scaly rashes on the trunk and proximal limbs, accompanied by severe pruritus that has been remained ineffective conventional treatments. She was diagnosed as persistent pityriasis rosea. As abrocitinib has been proved to be effective for many inflammatory diseases, therefore in this case, we tried abrocitinib for the patient, and a good result had been achieved.