Rheumatoid Arthritis – The Immaculate Infection

Author(s): J. Kelly Smith

Rheumatoid arthritis (RA), long considered a purely autoimmune disorder, is increasingly recognized as a disease potentially initiated or modulated by microbial triggers. The provocative phrase “the immaculate infection” underscores the possibility that infection—without overt illness—might be the inciting event in genetically susceptible individuals. This review explores microbial agents implicated in RA, including Porphyromonas gingivalis, Prevotella copri, Epstein-Barr virus, and Mycoplasma species. I discuss mechanisms such as molecular mimicry, citrullination, and dysbiosis, and consider the therapeutic and diagnostic implications of an infectious model for RA.