Two cases of a pityriasis rubra pilaris (PRP)-like skin eruption following administration of the Pfizer-BioNTech mRNA and AstraZeneca COVID-19 vaccines

ABSTRACT

Since the approval of vaccines for SARS-CoV-2, dermatologists have sought to characterize the adverse cutaneous effects associated with those vaccines. We describe two cases of pityriasis rubra pilaris (PRP) following vaccination against COVID-19. A 51-year-old man initially developed an erythematous scaly rash in his groin and over his knees 3 days following the first dose of the Pfizer COVID-19 vaccine. He presented after the second dose, as the rash worsened, affecting 60% body surface area (BSA). On examination there was an erythematous skin eruption extending from his scalp to both arms and the proximal thighs with sparing of the periumbilical area. There was no evidence of palmoplantar hyperkeratosis. The second case is a 51-year-old man presented with an itchy, erythematous rash affecting >80% BSA, 2 days after his first dose of the AstraZeneca COVID-19 vaccine. On examination there were multiple erythematous annular plaques, some of which were becoming more confluent, with islands of sparing. There was no evidence of palmoplantar hyperkeratosis. Differential diagnosis in both included drug-induced psoriasis and PRP. Histopathological diagnosis was consistent with PRP. Management of both cases included ruling out occult malignancy and infectious causes. Both patients were treated with acitretin and topical steroids. It is important to recognize this serious adverse event early so appropriate treatment can be initiated. When the culprit is the COVID-19 vaccine, typical features like palmoplantar hyperkeratosis may not be present. If PRP occurs after the first dose then discussion with the patient, weighing the risks and benefits including worsening of disease compared with the possibility of severe disease/death from COVID-19, is needed.