Presumably recurrent Ureaplasma parvum infection in a female peritoneal dialysis patient: a case report and literature review.

BACKGROUND: Peritoneal dialysis-associated peritonitis (PDAP) caused by Ureaplasma parvum (U. parvum) is exceedingly rare, and its diagnosis is particularly challenging due to the organism's biological characteristics and the limitations of conventional detection methods. To date, only sporadic case reports are available, but the diagnostic processes and clinical characteristics of PDAP caused by U. parvum infection have not been comprehensively reported yet. CASE PRESENTATION: We report a 35-year-old female patient undergoing continuous ambulatory peritoneal dialysis (CAPD) who experienced three episodes of peritonitis within a six-month period. Despite empirical antibiotic therapy leading to clinical improvement, routine microbiological cultures of the dialysate remained negative during each episode. During the third episode, metagenomic next-generation sequencing (mNGS) of the peritoneal dialysis (PD) effluent finally detected U. parvum as the causative pathogen. Following removing a potential risk factor, an intrauterine device (IUD), and adjusting the antimicrobial therapy to intraperitoneal (IP) levofloxacin and oral azithromycin, the patient achieved complete recovery and successfully resumed PD. Based on this experience, we documented the characteristic clinical profile of such infections and proposed an exploratory clinical diagnosis and treatment flowchart. CONCLUSIONS: Patients with recurrent culture-negative PDAP, especially female with an IUD, should be evaluated for U. parvum infection as a potential pathogen. mNGS facilitates the rapid detection of pathogens that traditional methods may fail to identify. Effective management of such infections necessitates not only targeted antimicrobial therapy guided by precise pathogen identification, but also the removal of potential risk factors such as the IUD.