Rare case of Ureaplasma parvum septic arthritis in an immunocompetent patient

Mycoplasmatacea family comprises two genera: Mycoplasma and Ureaplasma. Ureaplasma parvum (previously known as U. urealyticum biovar 1) commonly colonises the urogenital tract in humans. Although Ureaplasma species have well-established pathogenicity in urogenital infections, its involvement in septic arthritis has been limited to prosthetic joint infections and immunocompromised individuals. We present a rare case of native right knee infection due to U. parvum identified using next-generation sequencing of microbial cell-free DNA testing and confirmed with PCR assays. This rare case of Ureaplasma septic arthritis was diagnosed using newer next-generation DNA sequencing diagnostic modalities and a literature review of prior cases, antibiotic coverage and antimicrobial resistance is incorporated as part of the discussion.