Abstract
Cutaneous adverse reactions to SARS-CoV-2 vaccines occur with an overall pooled incidence of 5%. These include local injection site reactions, immediate and delayed reactions, autoimmune reactions (such as lupus erythematosus, bullous pemphigoid, vasculitis, thrombotic immune thrombocytopenia), pityriasis rosea-like, and chilblains-like lesions. Flares of previous conditions such as herpes virus infection, lymphomatoid papulosis (LyP) and anaplastic large cell lymphoma may occur. Such rare lymphomatoid reactions have occurred after Pfizer/BioNTech COVID-19 mRNA (BNT162b2) and AstraZeneca (AZD1222) COVID-19 vaccines. Cutaneous reactions with pseudolymphomatous infiltrates have also rarely been reported and include cutaneous lymphoid hyperplasia at the injection site, pityriasis lichenoides et varioliformis acuta with CD30 expression, and LyP-like reactions. We describe a patient with this rare reaction mimicking LyP.
A 74-year-old female presented with a pruritic six-week eruption that started 2 weeks after receiving the second dose of COVID-19 Moderna vaccine. She had no history of medication use. Examination showed numerous erythematous eczematous papules, some excoriated and crusted, on bilateral upper arms and legs and upper back. A biopsy specimen showed prominent acanthosis with erosion and crust. A band-like and perivascular lymphocytic infiltrate with eosinophils was present in the superficial and mid dermis, with exocytosis. There were numerous CD30-positive atypical lymphocytes and the CD4:CD8 was prominently increased, suggestive of lymphomatoid papulosis, but the timing, acute eruption and morphology favored pseudolymphomatous CD30 (+) pseudolymphoma due to her vaccination.
Awareness of this phenomenon following COVID-19 vaccination is critical to distinguish benign lymphomatoid eruptions from true lymphoma.
