Epidemiology and Molecular Characterization of Mycoplasmosis in Northeastern Part of Italy, 2023.

Mycoplasma genitalium (MG) is a cell wall-deficient bacterial pathogen associated with several sexually transmitted infections (STIs), including nongonococcal urethritis, cervicitis, and pelvic inflammatory disease. In the context of increasing antibiotic resistance and the challenges in clinical management, molecular epidemiological data are crucial for supporting surveillance strategies. This study aimed to assess the prevalence and genetic diversity of M. genitalium infections in a tertiary care hospital located in Northeastern Italy. In 2023, 2524 subjects (1622 men and 902 women) were screened using real-time multiplex PCR for the detection of major urogenital pathogens. M. genitalium-positive samples were molecularly characterized using a locus-typing approach based on sequence polymorphisms in the mgpB gene and the MG309 locus, enabling enhanced strain discrimination. Results revealed an overall positivity rate of 7.4% (118 cases), with a significantly higher prevalence in men (10.2%) than in women (2.6%), and the highest detection rate found in rectal swab specimens. Coinfections were detected in 48% of M. genitalium-positive subjects, most commonly involving Ureaplasma urealyticum (24%) and Metamycoplasma hominis (14%). Molecular typing on 22 M. genitalium-positive samples revealed significant locus-specific genetic heterogeneity, alongside the presence of a dominant cluster of 14 isolates with closely related allele profiles, suggesting the circulation of predominant local M. genitalium alleles within the analysed population.