Abstract
Background/Objectives: Ureaplasma parvum (Up) is an opportunistic pathogen associated with urogenital tract infections, pregnancy complications, and reproductive system diseases. Advances in molecular diagnostics have expanded its pathogenic spectrum to include invasive conditions such as arthritis, meningitis, and pneumonia. However, the pathogenic significance of Up remains controversial. Methods: This study retrospectively analyzed nine adult cases of Up detected by metagenomic next-generation sequencing (mNGS) between 2023 and 2024. Results: Patients, aged 21 to 70 years, predominantly had underlying immunosuppressive conditions (66.7%). Infections involved the urinary system (44.4%), respiratory system (33.3%), and peritoneal cavity (22.2%). Symptomatic relief was achieved in five cases following treatment with tetracyclines, quinolones or tigecycline. Conclusions: These findings highlight Up as a potential causative agent of invasive infections, particularly in immunocompromised patients. Up has potential pathogenic significance, whether it is detected as a single pathogen or as a coexisting pathogen.