Antimicrobial resistance, genetic characterization, and molecular epidemiology of Ureaplasma species in males with infertility

Evaluation of commercial, customized microdilution plates for Ureaplasma parvum, Ureaplasma urealyticum, and Mycoplasma hominis antimicrobial susceptibility testing and determination of antimicrobial resistance prevalence in France

Antimicrobial susceptibility testing (AST) of human mycoplasmas using microdilution is time-consuming. In this study, we compared the performance of MICRONAUT-S plates (Biocentric-Bruker) designed for AST of Ureaplasma parvum, Ureaplasma urealyticum, and Mycoplasma hominis with the results using the Clinical & Laboratory Standards Institute (CLSI) reference method. Then, we investigated the prevalence and mechanisms of resistance to tetracyclines, fluoroquinolones, and macrolides in France in 2020 and 2021. The two methods were compared using 60 strains. For the resistance prevalence study, U. parvum-, U. urealyticum-, and M. hominis-positive clinical specimens were collected for 1 month each year in 22 French diagnostic laboratories. MICs were determined using the MICRONAUT-S plates. The tet(M) gene was screened using PCR, and fluoroquinolone resistance-associated mutations were screened using PCR and Sanger sequencing. Comparing the methods, 99.5% (679/680) MICs obtained using the MICRONAUT-S plates concurred with those obtained using the CLSI reference method. For 90 M. hominis isolates, the tetracycline, levofloxacin, and moxifloxacin resistance rates were 11.1%, 2.2%, and 2.2%, respectively, with no clindamycin resistance. For 248 U. parvum isolates, the levofloxacin and moxifloxacin resistance rates were 5.2% and 0.8%, respectively; they were 2.9% and 1.5% in 68 U. urealyticum isolates. Tetracycline resistance in U. urealyticum (11.8%) was significantly (P < 0.001) higher than in U. parvum (1.2%). No macrolide resistance was observed. Overall, the customized MICRONAUT-S plates are a reliable, convenient tool for AST of human mycoplasmas. Tetracycline and fluoroquinolone resistance remain limited in France. However, the prevalence of levofloxacin and moxifloxacin resistance has increased significantly in Ureaplasma spp. from 2010 to 2015 and requires monitoring.

IMPORTANCE

Antimicrobial susceptibility testing of human urogenital mycoplasmas using the CLSI reference broth microdilution method is time-consuming and requires the laborious preparation of antimicrobial stock solutions. Here, we validated the use of reliable, convenient plates designed for antimicrobial susceptibility testing that allows the simultaneous determination of the MICs of eight antibiotics of interest. We then investigated the prevalence and mechanisms of resistance of each of these bacteria to tetracyclines, fluoroquinolones, and macrolides in France in 2020 and 2021. We showed that the prevalence of levofloxacin and moxifloxacin resistance has increased significantly in Ureaplasma spp. from 2010 to 2015 and requires ongoing monitoring.

Ureaplasma infections: update on epidemiology, antimicrobial resistance, and pathogenesis

Human Ureaplasma species are being increasingly recognized as opportunistic pathogens in human genitourinary tract infections, infertility, adverse pregnancy, neonatal morbidities, and other adult invasive infections. Although some general reviews have focused on the detection and clinical manifestations of Ureaplasma spp., the molecular epidemiology, antimicrobial resistance, and pathogenesis of Ureaplasma spp. have not been adequately explained. The purpose of this review is to offer valuable insights into the current understanding and future research perspectives of the molecular epidemiology, antimicrobial resistance, and pathogenesis of human Ureaplasma infections. This review summarizes the conventional culture and detection methods and the latest molecular identification technologies for Ureaplasma spp. We also reviewed the global prevalence and mechanisms of antibiotic resistance for Ureaplasma spp. Aside from regular antibiotics, novel antibiotics with outstanding in vitro antimicrobial activity against Ureaplasma spp. are described. Furthermore, we discussed the pathogenic mechanisms of Ureaplasma spp., including adhesion, proinflammatory effects, cytotoxicity, and immune escape effects, from the perspectives of pathology, related molecules, and genetics.

Integrating the Human and Animal Sides of Mycoplasmas Resistance to Antimicrobials

Mycoplasma infections are frequent in humans, as well as in a broad range of animals. However, antimicrobial treatment options are limited, partly due to the lack of a cell wall in these peculiar bacteria. Both veterinary and human medicines are facing increasing resistance prevalence for the most commonly used drugs, despite different usage practices. To date, very few reviews have integrated knowledge on resistance to antimicrobials in humans and animals, the latest dating back to 2014. To fill this gap, we examined, in parallel, antimicrobial usage, resistance mechanisms and either phenotype or genotype-based methods for antimicrobial susceptibility testing, as well as epidemiology of resistance of the most clinically relevant human and animal mycoplasma species. This review unveiled common features and differences that need to be taken into consideration in a "One Health" perspective. Lastly, two examples of critical cases of multiple drug resistance are highlighted, namely, the human M. genitalium and the animal M. bovis species, both of which can lead to the threat of untreatable infections.

Biochemical and morphofunctional study of sperm of men infected with antibiotic-resistant strains of Ureaplasma urealyticum

Background: The role of UU in the pathogenesis of male infertility is currently not fully understood. Despite the widespread occurrence of antibiotic-resistant UU strains, there are virtually no data on their effect on the morphofunctional characteristics of the sperm and the biochemical parameters of the ejaculate. Aims: Comprehensive evaluation of the sperm fertility in men infected with antibiotic-resistant UU strains. Methods: The semen of men of active reproductive age (n=4752, age from 18 to 46 years, with the average age of 27.84.4 years) was studied. In the semen samples, UU was detected by the microbiological method (seeding on selective culture media with the subsequent identification and determination of the antibiotic sensitivity of the obtained isolates). The semen from men with mixed infections was excluded from the study. As a control, we used samples of ejaculates from healthy fertile men (n=67, age from 19 to 43 years, with the average age of 25.85.1 years). In the study of the ejaculate, the methods recommended by the WHO expert group were used. In addition to the standard spermogram, MAR tests (IgA, IgG and IgM) were performed, the degree of fragmentation of the sperm DNA was evaluated, the interaction of the sperm with hyaluronic acid was evaluated, as well, the activity of acrosine and neutral alpha-glucosidase was measured, the levels of zinc, citric acid, fructose and the level of glycodelin were determined. The study had been carried out between 2018 and 2021. Results: The most common resistance was to erythromycin (88.2%), less often to azithromycin (47.0%), tetracycline (41.7%). The resistance to doxycycline (7.7%), josamycin (5.9%), and medicamycin (5.8%) was relatively rare. In men infected with antibiotic-resistant UU strains, the most frequently observed anomalies of a standard spermogram were those of the motor characteristics of spermatozoa asthenozoo-spermia and those of the spermatozoa's morphology teratozoospermia. In the presence of polyresistant UU strains, a high degree of the sperm DNA fragmentation was more common (10.03% of cases) in respect to the cases of UU strains not resistant to antibiotics (5.92% of cases) or resistant to only one antibiotic (6.16% of cases). Abnormalities of the spermatozoa's interaction with hyaluronic acid were observed more often (more than 12% of cases) for antibiotic-resistant UU strains than for non-antibiotic-resistant UU strains (less than 4% of cases). In men infected with antibiotic-resistant UU strains, a decrease in the enzymatic activity of acrosin was often observed (29.71% of cases), most frequently among the cases with polyresistant strains (40.46% of cases). Conclusions: Antibiotic-resistant UU strains have a negative effect on the sperm fertility, of which the most pronounced negative effects are caused by polyresistant strains. We recommend measuring the acrosin activity when performing a spermogram for patients infected with UU. In the presence of polyresistant UU strains, it is advisable to assess the degree of the sperm DNA fragmentation. We recommend carrying out an antibioticogram before prescribing a treatment for ureaplasmosis.

Antimicrobial resistance in clinical isolates of Ureaplasma spp. from samples in Germany

Ureaplasma urealyticum and U parvum are mollicutes species that colonize the urogenital tract of many asymptomatic persons but are also thought to be associated with symptomatic infections. Using 170 strains isolated between 2016 and 2019 in a German university hospital, resistance was tested by a combination of commercial tests, molecular methods and determination of minimal inhibitory concentrations. Rates of resistance to macrolides, tetracyclines and fluoroquinolones were 0%, 4.1% and 7.1%, respectively.

Resistance to tetracyclines among clinical isolates of Mycoplasma hominis and Ureaplasma species: a systematic review and meta-analysis

BACKGROUND

Resistance to tetracyclines, the first-line treatment for urogenital infections caused by Mycoplasma hominis and Ureaplasma species, is increasing worldwide. The aim of the present study was to determine the global status of resistance to this class of antibiotics.

METHODS

Electronic databases were searched using keywords including 'Mycoplasma', 'Mycoplasma hominis', 'M. hominis', 'Ureaplasma', 'Ureaplasma urealyticum', 'Ureaplasma parvum', 'U. urealyticum', 'U. parvum', 'Ureaplasma species', 'resistance', 'antibiotic resistance', 'antibiotic susceptibility', 'antimicrobial resistance', 'antimicrobial susceptibility', 'tetracycline', 'doxycycline' and 'minocycline'. Finally, after some exclusions, 37 studies from different countries were included in the study and meta-analysis was performed on the data collected.

RESULTS

The midrange resistance rates for M. hominis and U. urealyticum/parvum to tetracycline, doxycycline and minocycline were 50.0%, 9.0% and 16.7% and 43.3%, 28.6% and 9.0%, respectively. A high level of heterogeneity was observed in all studies (I2 > 50%, P value < 0.05), except those representing doxycycline resistance in M. hominis isolates (I2 = 39.1%, P  = 0.02). No evidence of publication bias was observed in the studies and neither Egger's test nor Begg's test showed significant publication bias.

CONCLUSIONS

The results of the present study show that the overall resistance to tetracyclines is relatively high and prevalent among M. hominis and Ureaplasma species throughout the world. This highlights the importance of and necessity for regional and local antibiotic susceptibility testing before treatment choice as well as development of newer generations of tetracyclines to prevent antibiotic misuse, emergence and spread of resistant strains and, finally, the failure of treatment.