Track

Case Reports

Abstract

Rubella virus, in both its wild-type and vaccine form, has recently been shown to carry an association with cutaneous granulomas, even in immunocompetent patients. There has been a predilection for the development of these rubella-associated granulomas on the left upper arm, a common site for vaccination. We present an additional case of granulomatous inflammation with rubella positivity in the right lower leg presenting as subcutaneous nodules affecting bilateral lower extremities.

A 47-year-old female presented with a 5-year cyclic history of raised and draining subcutaneous nodules affecting her bilateral lower extremities. She had tried multiple therapies for a presumed diagnosis of erythema nodosum, including SSKI, hydroxychloroquine, and intralesional corticosteroids, all of which provided some, but not complete relief. Two separate biopsies were performed two years apart over the course of her disease, both of which demonstrated lobular granulomatous panniculitis with an inflammatory cell infiltrate consisting of mostly histiocytes and lymphocytes. The latter of these two biopsies additionally demonstrated 4+ immunohistochemical staining for the Rubella virus capsid antigen. The patient was started on upadacitinib, doxycycline, and hydroxychloroquine, and is currently improved and stable on this regimen. Further testing to determine whether the rubella virus is vaccine-derived or wild type within this patient’s granulomas is pending.

This case expands the clinical presentation of Rubella-associated granulomatous inflammation to include panniculitis. Further research is needed to further understand the role of rubella in granuloma formation.