A Case of Pityriasis Rosea Following Monkeypox Vaccination

Introduction: Pityriasis rosea (PR) is a well-known but uncommon, benign papulosquamous skin condition that often occurs after viral infections or vaccinations. The most commonly implicated vaccine is smallpox. Monkeypox (MPX), a related virus to smallpox within the orthopox family, has recently grown in public health concern. We present here a case of PR following MPX vaccination in an African-American man. Case Report: A 32-year old African-American man presented for evaluation of a one-month history of rash that first appeared as an isolated itching spot on his right mid-back, followed by papular eruptions on his trunk with extremity sparing. He denied recent illnesses, medication use including NSAIDs, or history of similar rash. He did report receiving his first MPX dose about one week prior to rash onset. Pityriasis rosea was diagnosed based on clinical presentation and suspected secondary to the patient’s MPX vaccine course. Conclusion: There are currently two available vaccines for MPX protection in the United States, both of which are vaccinia-based and developmentally related to the smallpox vaccine. Given the known association of smallpox and PR, PR reactions following MPX vaccination may occur.