Granulomas Gone Wild: Update of Rubella as an Evolving Trigger

The presentation discusses recent findings on granulomas and their association with rubella as an evolving trigger. The speaker, a dermatopathologist, explains the types of granulomas, their roles in containing infections, and the significance of identifying rubella viruses in patients with inborn areas of immunity. In 2014, research revealed that the rubella vaccine strain was present in certain granulomas, different from community-circulating strains. A follow-up study found that 71% of granuloma cases in immunocompromised patients tested positive for vaccine-derived rubella virus, leading to the designation of these conditions as immune deficiency-related vaccine-derived rubella granulomas. The speaker highlights that rubella, typically seen as a mild disease, can persist in immune-privileged sites and lead to complications. Emerging research links various granulomatous diseases in adults to wild-type rubella virus, prompting further investigations across the U.S. to understand the virus's localization and immune evasion mechanisms. Histologically, rubella-associated granulomas exhibit patterns different from other granulomas, necessitating specialized staining methods for accurate diagnosis. The presentation concludes with an overview of treatment challenges and ongoing research into effective therapies.