Genomic Insights and Recent Epidemiology of a Multidrug-Resistant Mycoplasma hominis Isolate in China: Implications for Clinical Management

Mycoplasma hominis (M. hominis) is an opportunistic pathogen linked to urogenital and neonatal infections; however, limited genetic and epidemiological data are available. Extragenital infections in healthy adults are rare, and effective antibiotics are species-specific, complicating diagnosis and treatment. Hence, this study aimed to elucidate the clinical process, update the epidemiological characteristics, and investigate the genomic features of a multidrug-resistant M. hominis isolate from an immunocompetent pleuropneumonia patient in China. The M. hominis isolate ZY_MH01 was recovered from pleural fluid and was identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and Whole Genome Sequencing (WGS). The completed genome was annotated using the NCBI Prokaryotic Genome Annotation Pipeline (PGAP). Snippy v4.4.5 was utilized to conduct a core genome single nucleotide polymorphism (cgSNP) analysis between ZY_MH01 and 50 M. hominis strains from the NCBI GenBank database. Subsequently, phylogenies were constructed using IQtree v2.0.3 and visualized by iTOL. Antimicrobial resistance genes and susceptibility were identified by CARD RGI v6.0.3 and VITEK 2 Compact System. The antimicrobial resistance mutation in gene parC (S91I) was found in the genome. Phylogenetic analysis revealed that ZY_MH01 and strains from the NCBI database were epidemiologically related, with ZY_MH01's closest relatives being in the same city and sharing the same resistance and virulence genes. M. hominis should be considered a potential cause of pulmonary infection, particularly in patients unresponsive to broad-spectrum antibiotics. This study provides a detailed analysis of M. hominis epidemiology, highlighting regional evolutionary relationships among strains.