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This article discusses the increasing resistance of Mycoplasma genitalium, a sexually transmitted infection, to antimicrobials in Queensland, Australia. The study examined samples collected between 2016 and 2021 and found that fluoroquinolone resistance mutations in the parC and gyrA genes were common, particularly the GyrA-M95I mutation. The presence of concurrent ParC-S83I and GyrA-M95I mutations was associated with lower cure rates with certain antibiotics. The study also identified specific genotypes of M. genitalium that were enriched with these resistant mutations, suggesting the circulation of highly resistant strains in large sexual networks. [Extracted from the article]

Mycoplasma hominis and Ureaplasma species infections in the post‐transplant setting are believed to be donor‐derived and can be associated with poor outcomes. Difficulty in culturing and identifying these organisms is a significant barrier to diagnosis and early intervention. Tetracyclines, macrolides and fluoroquinolones are the mainstay treatments to cure these infections; however, there are increasing reports of antibiotic resistance. In this case series, we report our single‐centre experience with M. hominis and U. urealyticum infection after lung transplantation (9 recipients, all men, mean age 56 years). Delayed diagnosis was common. Young donor age (mean age 23 yrs) and high‐risk donor social history (67%) were repeatedly noted in these cases, and all infections were associated with significant morbidity (anastomosis and sternal wound infection, empyema, mediastinitis, pericarditis). Two patients died; with one directly related to Ureaplasma urealyticum infection. In conclusion post lung transplant M. hominis, and U. urealyticum infections are challenging and carry high morbidity. More prospective studies are required to assess the true prevalence, full spectrum of complications and utility of molecular diagnostics to aid early diagnosis and identify antibiotic susceptibility of Mycoplasma and Ureaplasma infections in the post‐lung transplant setting. [ABSTRACT FROM AUTHOR]

Background: Mycoplasma genitalium infection is a sexually transmitted infection that has rapidly become resistant to mainstay treatments. While individualized treatment approaches have been recommended and adopted for macrolides, individualized therapy for fluoroquinolones has not yet been explored, due to a lack of commercial molecular assays and a lack of confidence in specific mutations associated with resistance. In another recent study, we defined a clear role and diagnostic utility in focusing on the absence of resistance mutations to inform microbial cure with fluoroquinolone antimicrobials.Methods: We developed two proof-of-concept molecular tests that focus on detection of M. genitalium and characterization of WT parC sequences that are strongly linked to fluoroquinolone susceptibility.Results: We screened a total of 227 M. genitalium-positive samples using novel molecular beacon and dual hybridization probe assays. These assays were able to detect M. genitalium and characterize fluoroquinolone susceptibility in 143/227 (63%) samples, based on clear differences in melting peak temperatures. The results of these molecular assays were in 100% agreement with 'gold standard' Sanger sequencing. Additionally, WT parC sequences were readily distinguished from M. genitalium samples harbouring parC mutations of known or suspected clinical significance. The ability of the assays to successfully characterize fluoroquinolone susceptibility and resistance was reduced in low M. genitalium load samples.Conclusions: These proof-of-concept assays have considerable potential to improve individualized treatment approaches and rationalize tests of cure for M. genitalium infection. The ability to initiate individualized treatment in up to two-thirds of cases will enhance antimicrobial stewardship for this challenging pathogen. [ABSTRACT FROM AUTHOR]

Background: Mycoplasma genitalium was recently added to the CDC's antimicrobial resistance threats 'watch list', as it has rapidly become resistant to mainstay treatments. In Australia, treatment failure with fluoroquinolones remain commonplace, even when Sanger sequencing fails to identify evidence of resistance mutations.Methods: Suspecting that Sanger sequencing may miss low-load mixed infections, we applied three additional PCR-based approaches (allele-specific primer-based PCR, probe-based PCR and amplicon deep sequencing) to detect mutations associated with fluoroquinolone susceptibility/resistance. We focused on resistance mutations at amino acid positions 83 and 87 of parC, as these were previously shown to be common in Australia.Results: Our results showed evidence of mixtures of fluoroquinolone-susceptible and -resistant strains in up to 27/423 samples (6.4%). These included 1 sample that was indicated to be mixed by Sanger sequencing and all three additional PCR methods, 6 samples detected by two or more of the additional PCRs but not by Sanger sequencing and finally 20 samples that were detected by only one of the additional PCR methods. A key question was whether Sanger sequencing failed to detect fluoroquinolone resistance in any samples; overall, we observed that Sanger sequencing failed to detect fluoroquinolone resistance in up to 3.8% (16/423) of samples.Conclusions: The presence of mixed susceptibility infections may have important implications for clinical patient management and stresses the need for appropriate detection of resistance and selection of antimicrobials to ensure appropriate treatment of M. genitalium infections. [ABSTRACT FROM AUTHOR]