Antimicrobial Resistance in Clinical Ureaplasma spp. and Mycoplasma hominis and Structural Mechanisms Underlying Quinolone Resistance

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.

Native Joint Septic Arthritis

Native joint septic arthritis (NJSA) is a severe and rapidly progressing joint infection, predominantly bacterial but also potentially fungal or viral, characterized by synovial membrane inflammation and joint damage, necessitating urgent and multidisciplinary management to prevent permanent joint damage and systemic sepsis. Common in large joints like knees, hips, shoulders, and elbows, NJSA's incidence is elevated in individuals with conditions like rheumatoid arthritis, diabetes, immunosuppression, joint replacement history, or intravenous drug use. This review provides a comprehensive overview of NJSA, encompassing its diagnosis, treatment, antibiotic therapy duration, and surgical interventions, as well as the comparison between arthroscopic and open debridement approaches. Additionally, it explores the unique challenges of managing NJSA in patients who have undergone graft anterior cruciate ligament (ACL) reconstruction. The epidemiology, risk factors, pathogenesis, microbiology, clinical manifestations, diagnosis, differential diagnosis, antibiotic treatment, surgical intervention, prevention, and prophylaxis of NJSA are discussed, highlighting the need for prompt diagnosis, aggressive treatment, and ongoing research to enhance patient outcomes.

Disseminated septic arthritis caused by Ureaplasma urealyticum in an immunocompromised patient with hypogammaglobulinemia after rituximab therapy

PURPOSE

Ureaplasma urealyticum is a rare pathogen associated with septic arthritis that predominantly affects patients with hypogammaglobulinemia. Bacterial identification of fastidious organisms is challenging because they are undetectable by routine culture testing. To the best of our knowledge, this is the first report of septic arthritis induced by U. urealyticum infection in Japan.

CASE DESCRIPTION

We describe the case of a 23-year-old Japanese female with secondary hypogammaglobulinemia (serum immunoglobulin level < 500 mg/dL), identified 8 years after treatment with rituximab. The patient presented with persistent fever and polyarthritis that were unresponsive to ceftriaxone and prednisolone. Contrast-enhanced computed tomography and gallium-67 scintigraphy revealed effusion and inflammation in the left sternoclavicular, hip, wrist, knee, and ankle joints. Although Gram staining and bacterial culture of the drainage fluid from the left hip joint were negative, the condition exhibited characteristics of purulent bacterial infection. The patient underwent empirical treatment with doxycycline, and her symptoms promptly resolved. Subsequent 16S ribosomal RNA (rRNA) gene sequencing of the joint fluid confirmed the presence of U. urealyticum, leading to the diagnosis of septic arthritis. Combination therapy with doxycycline and azithromycin yielded a favorable recovery from the inflammatory status and severe arthritic pain.

CONCLUSION

This case highlights U. urealyticum as a potential causative agent of disseminated septic arthritis, particularly in patients with hypogammaglobulinaemia. The 16S rRNA gene analysis proved beneficial for identifying pathogens in culture-negative specimens, such as synovial fluid, in suspected bacterial infections.

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.

Postoperative mediastinitis and sternal osteitis after cardiac surgery caused by Mycoplasma hominis: A case report

BACKGROUND

Mediastinitis and sternal osteitis are critical complications in cardiac surgery. Cases of these complications caused by Mycoplasma hominis are extremely rare.

CASE PRESENTATION

We present a case of mediastinitis and sternal osteitis caused by M. hominis infection following ascending aortic replacement surgery. Whole gene sequencing analysis suggested the genitourinary tract as the most likely source of this M. hominis infection. Successful infection control was achieved through a regimen of moxifloxacin treatment. Additionally, a notable correlation was observed between serum levels of interleukin-6 and M. hominis infection.

CONCLUSIONS

The significance of M. hominis as a potential cause of postoperative infection in cardiac surgery is still not fully recognized. Special attention should be paid to patients with bacteriologically negative infections, as M. hominis should not be disregarded, despite its rarity.

Trends of fluoroquinolones resistance in Mycoplasma and Ureaplasma urogenital isolates: Systematic review and meta-analysis

BACKGROUND

Mycoplasma and Ureaplasma spp. especially M. hominis, U. parvum, and U. urealyticum recognized as an important cause of urogenital infections. Sake of the presence of antibiotic resistance and a continuous rise in resistance, the treatment options are limited, and treatment has become more challenging and costlier.

OBJECTIVES

Therefore, this meta-analysis aimed to estimate worldwide resistance rates of genital Mycoplasmas and Ureaplasma to fluoroquinolones (ciprofloxacin, ofloxacin, moxifloxacin, and levofloxacin) agents.

METHODS

We searched the relevant published studies in PubMed, Scopus, and Embase from until 3, March 2022. All statistical analyses were carried out using the statistical package R.

RESULTS

The 30 studies included in the analysis were performed in 16 countries. In the metadata, the proportions of ciprofloxacin, ofloxacin, moxifloxacin, and levofloxacin resistance in Mycoplasma and Ureaplasma urogenital isolates were reported 59.8% (95% CI 49.6, 69.1), 31.2% (95% CI 23, 40), 7.3% (95% CI 1, 31), and 5.3% (95% CI 1, 2), respectively. According to the meta-regression, the ciprofloxacin, ofloxacin, moxifloxacin, and levofloxacin rate increased over time. There was a statistically significant difference in the fluoroquinolones resistance rates between different continents/countries (P < 0.05).

CONCLUSIONS

Based on the results obtained in this systematic review and meta-analysis we recommend the use of the newer group of fluoroquinolones especially levofloxacin as the first choice for the treatment of genital mycoplasmosis, as well as ofloxacin for the treatment of genital infections caused by U. parvum.

Normospermic Patients Infected With Ureaplasma parvum: Role of Dysregulated miR-122-5p, miR-34c-5, and miR-141-3p

Background

Ureaplasma parvum (UP) is a causative agent of non-gonococcal urethritis, involved in the pathogenesis of prostatitis and epididymitis, and it could impair human fertility. Although UP infection is a frequent cause of male infertility the study evidence assessing their prevalence and the association in patients with infertility is still scarce. The molecular processes leading to defects in spermatozoa quality are not completely investigated. MicroRNAs (miRNAs) have been extensively reported as gene regulatory molecules on post-transcriptional levels involved in various biological processes such as gametogenesis, embryogenesis, and the quality of sperm, oocyte, and embryos.

Methods

Therefore, the study design was to demonstrate that miRNAs in body fluids like sperm could be utilized as non-invasive diagnostic biomarkers for pathological and physiological conditions such as infertility. A post-hoc bioinformatics analysis was carried out to predict the pathways modulated by the miRNAs dysregulated in the differently motile spermatozoa.

Results

Here it is shown that normospermic patients infected by UP had spermatozoa with increased quantity of superoxide anions, reduced expression of miR-122-5p, miR-34c-5, and increased miR-141-3p compared with non-infected normospermic patients. This corresponded to a reduction of sperm motility in normospermic infected patients compared with normospermic non-infected ones. A target gene prediction presumed that an essential role of these miRNAs resided in the regulation of lipid kinase activity, accounting for the changes in the constitution of spermatozoa membrane lipids caused by UP.

Conclusions

Altogether, the data underline the influence of UP on epigenetic mechanisms regulating spermatozoa motility.

Mollicutes-related infections in thoracic surgery including lung and heart transplantation: A systematic review

BACKGROUND

Urogenital Mollicutes, that is, Mycoplasma hominis and Ureaplasma spp., can colonize the urogenital tract. While urogenital colonization is frequent, infections are rare but should not be missed. Furthermore, extragenital infections are even rarer. Over the past years, they have been increasingly documented as a cause of hyperammonemia syndrome (HS) and post-surgical infections. We review the literature on studies focused on post-surgical infections and HS involving urogenital Mollicutes after thoracic surgery including lung (LTR) and heart (HTR) transplantation.

METHODS

A systematic review was performed by searching PubMed/Medline case reports, case series, cohort studies, and clinical trials. Cases of infections and HS by urogenital Mollicutes after HTR and LTR transplantations were reported.

RESULTS

Overall, urogenital Mollicutes were associated with 15 HS, 31 infections in HTR and LTR, and 18 post-thoracic surgical infections in another context. Post-surgical infections were reported in all contexts. They were mainly due to M hominis, the only species that could cultivate on standard enriched agar forming pinpoint colonies after 3-5 days of incubation. Microbiologists should be prompted to pinpoint colonies even if the examination of Gram-staining is negative. The patients' management required surgical treatment and antimicrobials, almost always tetracyclines and/or fluoroquinolones. Conversely, HS occurred almost exclusively in bilateral LTR and is more likely due to Ureaplasma spp. As Ureaplasma spp. do not cultivate on standard media, the microbiological diagnosis was performed using molecular methods.

CONCLUSIONS

Infections involving urogenital Mollicute should be considered in LTR with HS. The overall rate of mortality is high and might be due in part to delay in etiologic diagnosis. Post-surgical infections were reported in all contexts. The route of contamination with Mollicutes remains unknown in HTR and non-transplant surgery, but evidence of transmission from donors has been documented for LTR.

Deciphering the genetic basis of resistome and virulome diversity among multidrug-resistant Mycoplasma hominis

Mycoplasma hominis, a commensal bacterium that commonly inhabits the genital tract, leading to infections in both the genitourinary and extragenital regions. However, the antimicrobial resistance and pathogenic mechanisms of M. hominis isolated from extra-urogenital cystic abscess is largely unknown. This study reports the genomic epidemiological characteristics of a M. hominis isolate recovered from a pelvic abscess sample in China. Genomic DNA was extracted and sequenced using Illumina HiSeq X Ten platform. De novo assembly was performed and in silico analysis was accomplished by multiple bioinformatics tools. For phylogenomic analysis, publicly available M. hominis genomes were retrieved from NCBI GenBank database. Whole genome sequencing data showed that the genome size of M. hominis MH4246 was calculated as 679,746 bp, with 558 protein-coding sequences and a G + C content of 26.9%. M. hominis MH4246 is resistant to fluoroquinolones and macrolides, harboring mutations in the quinolone resistance-determining regions (QRDRs) (GyrA S153L, ParC S91I and ParE V417I) and 23S rRNA gene (G280A, C1500T, T1548C and T2218C). Multiple virulence determinants, such as tuf, hlyA, vaa, oppA, MHO_0730 and alr genes, were identified. Phylogenetic analysis showed that the closest relative of M. hominis MH4246 was the strain MH-1 recovered from China, which differed by 3490 SNPs. Overall, this study contributes to the comprehension of genomic characteristics, antimicrobial resistance patterns, and the mechanisms underlying the pathogenicity of this pathogen.

Antimicrobial Activity of N,N-Diethyldithiocarbamate against Ureaplasma parvum and Ureaplasma urealyticum

Ureaplasma species (Ureaplasma spp.) are commonly found as commensals in the human urogenital tracts, although their overgrowth can lead to infection in the urogenital tract and at distal sites. Furthermore, ureaplasmas lack a cell wall and do not synthesize folic acid, which causes all β-lactam and glycopeptide antibiotics, and sulfonamides and diaminopyrimidines, to be of no value. The antibiotics used in therapy belong to the fluoroquinolone, tetracycline, chloramphenicol and macrolide classes. However, the growing incidence of antibiotic-resistant Ureaplasma spp. in the population becomes a problem. Thus, there is a need to search for new drugs effective against these bacteria. Since 1951, the FDA-approved, well-tolerated, inexpensive, orally administered drug disulfiram (DSF) has been used in the treatment of chronic alcoholism, but recently, its antimicrobial effects have been demonstrated. The main biological metabolite of DSF, i.e., N,N-diethyldithiocarbamate (DDC), is generally believed to be responsible for most of the observed pharmacological effects of DSF. In the presented studies, the effect of DDC at concentrations of 2 µg/mL, 20 µg/mL and 200 µg/mL on the growth and survival of Ureaplasma urealyticum and Ureaplasma parvum was tested for the first time. The results indicated that all the used DDC concentrations showed both bacteriostatic and bactericidal activity against both tested strains.

Global analysis on the mutations associated with multidrug-resistant urogenital mycoplasmas and ureaplasmas infection: a systematic review and meta-analysis

BACKGROUND

The emergence of multidrug-resistant (MDR) strains of genital pathogens, notably Mycoplasma genitalium and Ureaplasma spp., constitutes a significant global threat today. The present study aimed to evaluate the prevalence and trend of changes in MDR mycoplasma and ureaplasma strains.

METHODS

An exhaustive search was performed across the ISI Web of Science, PubMed, Scopus, ScienceDirect, and Google Scholar databases to accumulate relevant studies without restrictions until April 2023. We used event rate and corresponding 95% confidence intervals to determine the frequency of resistance-related mutations and examine the trend of antibiotic resistance changes.

RESULTS

The data from 27 studies, including 24,662 patients across 14 countries, were evaluated. Out of the total studies, 20 focused on M. genitalium infections, and five on Ureaplasma spp. The frequency of resistance-associated mutations to macrolides, tetracyclines, and fluoroquinolones in clinical strains of M. genitalium was 43.5%, 13.1%, and 18.6%, respectively. The prevalence of M. genitalium strains with double resistance and MDR was 11.0% and 17.4%, respectively. The incidence of both double-drug-resistant and MDR strains was higher in the World Health Organization (WHO) Western Pacific Region than in European and American populations. For Ureaplasma strains, resistance-associated mutations to macrolides, tetracyclines, and fluoroquinolones were 40.8%, 25.7%, and 90.3%, respectively. The rate of antibiotic resistance was higher in the African population compared to the European and WHO Western Pacific Regions. The rate of MDR Ureaplasma infections was 13.2%, with a higher incidence in the African population compared to the WHO Western Pacific and European regions.

CONCLUSION

The proliferation and spread of MDR Mycoplasma and Ureaplasma strains present a significant public health challenge. The situation is indeed alarming, and the rising trend of MDR M. genitalium and MDR Ureaplasma infections suggests that therapies involving macrolides and fluoroquinolones may become less effective.

Mycoplasma hominis necrotising pneumonia in an immunocompetent adult male

Mycoplasma hominis, a common coloniser of the urogenital tract, is a rare cause of respiratory infections in an immunocompetent patient. M. hominis lacks a cell wall and can be difficult to identify with standard culture methods posing difficulties in diagnosis and treatment. We describe a case of M. hominis pneumonia in an immunocompetent man in his early 40s without any risk factors presenting with a cavitary lesion who developed empyema and necrotising pneumonia requiring surgical debridement. Identification of M. hominis and subsequent modification of antibiotic therapy led to favourable outcome. M. hominis should be considered in the differential diagnosis of patients with treatment resistant pneumonia especially in patients with trauma, intracranial injury, lung transplant or if immunocompromised. While M. Hominis is naturally resistant to all antibiotics that target cell wall synthesis, we recommend levofloxacin or other fluoroquinolone to most effectively treat with doxycycline as a potential alternative.

Molecular docking and dynamics simulation approach of Camellia sinensis leaf extract derived compounds as potential cholinesterase inhibitors

The tea plant (Camellia sinensis) belongs to the family Theaceae and contains many phytochemicals that are effective against various diseases, including neurodegenerative disorders. In this study, we aimed to characterize the phytochemicals present in the methanolic and n-hexane leaf extracts of C. sinensis using GC-MS, FTIR, and UV-visible analysis. We detected a total of 19 compounds of different chemical classes. We also performed molecular docking studies using the GC-MS detected phytochemicals, targeting acetylcholinesterase (AChE, PBD ID: 4BDT) and butyrylcholinesterase (BChE, PDB ID: 6QAB), which are responsible for the breakdown of the neurotransmitter acetylcholine (ACh). This breakdown leads to dementia and cognitive decline in Alzheimer's patients. The compounds Ergosta-7,22-dien-3-ol, (3.beta.,5.alpha.,22E)- and Benzene, 1,3-bis(1,1-dimethylethyl) showed better binding affinity against AChE, while dl-.alpha.-Tocopherol and Ergosta-7,22-dien-3-ol, (3.beta.,5.alpha.,22E)- showed better binding affinity against BChE. We determined the stability and rigidity of these best docked complexes through molecular dynamics simulation for a period of 100 ns. All complexes showed stability in terms of SASA, Rg, and hydrogen bonds, but some variations were found in the RMSD values. Our ADMET analysis revealed that all lead compounds are non-toxic. Therefore, these compounds could be potential inhibitors of AChE and BChE.

Graphical abstract

In Vitro Activity of Delafloxacin and Finafloxacin against Mycoplasma hominis and Ureaplasma Species

The in vitro activity of two new fluoroquinolones, delafloxacin and finafloxacin, were evaluated against M. hominis and Ureaplasma spp. The MICs of delafloxacin, finafloxacin, and two classical fluoroquinolones (moxifloxacin and levofloxacin) were tested against 29 M. hominis and 67 Ureaplasma spp. isolates using the broth microdilution method. The molecular mechanisms underlying fluoroquinolone resistance were also investigated. Delafloxacin exhibited low MICs against M. hominis and Ureaplasma spp., including the levofloxacin-resistant isolates. For M. hominis, delafloxacin showed low MIC₉₀ value of 1 μg/mL (MIC range, <0.031 -1 μg/mL) compared to 8 μg/mL for finafloxacin, 16 μg/mL for moxifloxacin, and 32 μg/mL for levofloxacin. For U. parvum and U. urealyticum, delafloxacin had low MIC₉₀ values (U. parvum, 2 μg/mL; U. urealyticum, 4 μg/mL) compared to 16 -32 μg/mL for finafloxacin, 16 μg/mL for moxifloxacin, and 32 - >32 μg/mL for levofloxacin. The two mutations GyrA S153L and ParC S91I were commonly identified in fluoroquinolone-resistant M. hominis, and ParC S83L was the most frequent mutation identified in fluoroquinolone-resistant Ureaplasma spp. Delafloxacin displayed lower MICs against fluoroquinolone-resistant isolates of both M. hominis and Ureaplasma spp. that have mutations in the quinolone resistance determining regions (QRDRs) than the two classical fluoroquinolones. Delafloxacin is a promising fluoroquinolone with low MICs against fluoroquinolone-resistant M. hominis and Ureaplasma spp. Our study confirms the potential clinical use of delafloxacin in treating antimicrobial-resistant M. hominis and Ureaplasma spp. infections.

IMPORTANCE Fluoroquinolone resistance in Mycoplasma hominis and Ureaplasma spp. is on the rise globally, which has compromised the efficacy of the currently available antimicrobial agents. This study evaluated the antimicrobial activity of two new fluoroquinolones, delafloxacin and finafloxacin, for the first time, against M. hominis and Ureaplasma spp. clinical isolates. Delafloxacin and finafloxacin displayed different antimicrobial susceptibility profiles against M. hominis and Ureaplasma spp. in vitro. Delafloxacin was found to be more effective against M. hominis and Ureaplasma spp. than three classical fluoroquinolones (finafloxacin, moxifloxacin, and levofloxacin). Finafloxacin displayed activity similar to moxifloxacin but superior to levofloxacin against M. hominis and Ureaplasma spp. Our findings demonstrate that delafloxacin is a promising fluoroquinolone with outstanding activity against fluoroquinolone-resistant M. hominis and Ureaplasma spp.

Clinical and Microbiological Characterization of Bloodstream Infections Caused by Mycoplasma hominis: An Overlooked Pathogen

Introduction

Methods

Results

Conclusions

Supplementary Information

Antibiotic resistance among clinical Ureaplasma isolates from Cuban individuals between 2013 and 2018

Introduction. Acquired resistance against the antibiotics that are active against Ureaplasma species has been described.Hypothesis/Gap Statement. Diagnostics combined with antimicrobial sensitivity testing are required for therapeutic guidance.Aim. To report the prevalence of antimicrobial resistance among Cuban Ureaplasma isolates and the related molecular mechanisms of resistance.Methodology. Traditional broth microdilution assays were used for antimicrobial sensitivity testing in 262 clinical Ureaplasma species isolates from Cuban patients between 2013 and 2018, and a subset of samples were investigated in parallel with the commercial MYCO WELL D-ONE rapid culture diagnostic assay. The underlying molecular mechanisms for resistance were determined by PCR and sequencing for all resistant isolates.Results. Among the tested isolates, the tetracycline and erythromycin resistance rates were 1.9 and 1.5%, respectively, while fluoroquinolone resistance was not found. The tet(M) gene was found in all tetracycline-resistant isolates, but also in two tetracycline-susceptible Ureaplasma clinical isolates. We were unable to determine the underlying mechanism of erythromycin resistance. The MYCO WELL D-ONE kit overestimated tetracycline and erythromycin resistance in Ureaplasma spp. isolates.Conclusions. Although low levels of antibiotic resistance were detected in Cuban patients over a 5-year period, continued surveillance of the antibiotic susceptibility of Ureaplasma is necessary to monitor possible changes in resistance patterns.

Detection and Evaluation of Macrolide Resistance (Erythromycin) in Mycoplasma hominis Isolated from Endocervical Specimens of Patients Referring to Ibn Sina Infertility Treatment Centre, Tehran, Iran

Background

Mycoplasma hominis (M. hominis) is an important cause of bacterial infections of the genital tract. Macrolides are the first selective agents used to treat mycoplasma infections. However, widespread use of macrolides has led to a rapid and global emergence of macrolide-resistant strains. We evaluated macrolide resistance in M. hominis isolated from endocervical specimens of patients who referred to Ibn Sina Infertility Centre in Tehran, Iran.

Materials and Methods

In this cross-sectional descriptive-analytical study, 160 samples of Dacron endocervix swabs (80 infertile patient samples and 80 healthy controls) were collected and transferred to the laboratory. All samples were cultured in liquid pleuropneumonia-like organisms (PPLO) broth and PPLO agar solid media. After culturing and genome extraction, polymerase chain reaction (PCR) was performed using specific primers. Then, minimum inhibitory concentration (MIC) was obtained using the broth microdilution method. The MIC was recorded and reported for all samples positive for M. hominis against erythromycin.

Results

From the 160 endocervical specimens cultured in PPLO agar medium, 19 cases (23.75%) were positive. A total of 35 cases (42.5%) were positive using specific primers of M. hominis species. MIC results from all samples positive for M. hominis were measured against erythromycin. All of the M. hominis samples were resistant to erythromycin.

Conclusion

The results of the present study showed that a significant percentage of infertile women were infected with M. hominis. Also, MIC results from the broth microdilution method indicated that all strains positive for M. hominis were also resistant to erythromycin.

Postoperative mediastinitis after cardiac surgery caused by Mycoplasma hominis: a case report

BACKGROUND

Mycoplasma hominis is a human commensal bacterium of the urogenital tract, and extragenital infection caused by M. hominis has rarely been reported. The identification of M. hominis is challenging, and surgeons are generally not aware that this bacteria can cause postoperative infection. Here, we report a rare case of postoperative mediastinitis caused by M. hominis after cardiac surgery in an immunocompetent patient.

CASE PRESENTATION

A 54-year-old man presented with pain and purulent discharge from the wound after aortic valve replacement and patent foramen ovale closure. However, Gram staining and culture of bacteria from the purulent discharge was negative, and empiric sulbactam/ampicillin therapy was not effective. This patient developed mediastinitis and rupture of a pseudoaneurysm of the ascending aorta caused by mediastinitis, and re-operation was performed. Then, postoperative mediastinitis caused by M. hominis or Ureaplasma species was suspected and bacterial cultures targeting these pathogens were performed. M. hominis was identified from abscess and tissue obtained from the surgical site and urine. A final diagnosis of postoperative mediastinitis caused by M. hominis was determined. The patient was initially treated with levofloxacin and then with minocycline for 3 weeks. The patient's clinical condition improved; the patient was transferred to another hospital.

CONCLUSION

The role of M. hominis as a cause of postoperative infection might be underestimated in cardiac surgery. M. hominis should be considered when culture-negative purulent discharge is observed or there is no response to standard empiric treatment of postoperative infections.

Defining Fluoroquinolone Resistance-Mediating Mutations from Non-Resistance Polymorphisms in Mycoplasma hominis Topoisomerases

Often dismissed as a commensal, Mycoplasma hominis is an increasingly prominent target of research due to its role in septic arthritis and organ transplant failure in immunosuppressed patients, particularly lung transplantation. As a mollicute, its highly reductive genome and structure render it refractile to most forms of treatment and growing levels of resistance to the few sources of treatment left, such as fluoroquinolones. We examined antimicrobial susceptibility (AST) to fluoroquinolones on 72 isolates and observed resistance in three (4.1%), with corresponding mutations in the quinolone resistance-determining region (QRDR) of S83L or E87G in gyrA and S81I or E85V in parC. However, there were high levels of polymorphism identified between all isolates outside of the QRDR, indicating caution for a genomics-led approach for resistance screening, particularly as we observed a further two quinolone-susceptible isolates solely containing gyrA mutation S83L. However, both isolates spontaneously developed a second spontaneous E85K parC mutation and resistance following prolonged incubation in 4 mg/L levofloxacin for an extra 24–48 h. Continued AST surveillance and investigation is required to understand how gyrA QRDR mutations predispose M. hominis to rapid spontaneous mutation and fluoroquinolone resistance, absent from other susceptible isolates. The unusually high prevalence of polymorphisms in M. hominis also warrants increased genomics’ surveillance.

Phenotypic Antimicrobial Susceptibility and Genotypic Characterization of Clinical Ureaplasma Isolates Circulating in Shanghai, China

There is a growing global concern regarding the rise of antimicrobial resistance among Ureaplasma spp. isolates. However, studies on the antimicrobial susceptibility profiles, resistance mechanisms, and clonality of Ureaplasma spp. clinical isolates are still limited and cover only some geographic regions. Firstly, Ureaplasma species from the urogenital tracts of patients in Shanghai, China, were isolated by using the culture medium (A8 and 10B broth), and identified the genotype by polymerase chain reaction (PCR). Secondly, the antimicrobial susceptibility tests were determined by using broth microdilution assay. Then, the resistance genetic determinants to fluoroquinolones (FQs), macrolides, and tetracyclines were investigated through PCR/DNA sequencing. Finally, the molecular epidemiology of Ureaplasma species was studied by multilocus sequence typing (MLST). Among 258 isolates, Ureaplasma parvum (UPA) and Ureaplasma urealyticum (UUR) were found in 226 (87.60%) and 32 (12.40%) isolates, respectively. The minimum inhibitory concentrations (MICs) of 258 Ureaplasma spp. strains ranged from 0.015 to 64μg/ml for all 11 kinds of antimicrobials. Regardless of species, the isolates were most sensitive to AZI (1.94%), JOS (3.49%), and CLA (4.23%). Among them, there were 39 (15.12%) multidrug-resistant (MDR) strains, including 32 UPA isolates. The resistance rates of UPA to CIP (91.59%), and ROX (36.28%) were significantly higher than those of UUR. Twenty six FQ-resistant isolates had amino acid substitutions in gyrA and in parC (Ser83Leu). Mutations were detected in genes encoding ribosomal proteins L4 (Thr84Ile) and L22 (Ser81Pro) in macrolide-resistant isolates. Tet(M) was found in four UPA isolates. These mutations were mainly found in UPA isolates. Sequence type 1 (ST1) was the predominant ST, which contained 18 isolates. In conclusion, this study showed a higher resistance rate (especially to ROX and CIP), higher substitution rate, and higher MDR rate among UPA strains. The most active antimicrobial agents were AZI, JOS, and CLA. Identifying UPA or UUR in clinical isolates could help clinicians to choose appropriate drugs for treatment. The main resistance mechanisms may involve gene substitution of Ser83Leu in parC and Ser81Pro in L22. ST1 was the predominant ST of Ureaplasma isolates with MDR to FQs and macrolides in Shanghai, China.

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.

Evaluation of the MYCOPLASMA IST3 urogenital mycoplasma assay in an international multicentre trial

OBJECTIVES

To evaluate the accuracy, susceptibility and specificity of MYCOPLASMA IST3, the next generation of the most popular culture-based in vitro diagnostic device designed to detect, identify and test the susceptibility of urogenital mycoplasma infections.

METHODS

MYCOPLASMA IST3 was evaluated against culture- and molecular-based gold standard methodologies to detect, identify, enumerate and determine antimicrobial resistance for Mycoplasma hominis and Ureaplasma species in 516 clinical samples collected across France, Serbia and the UK. Sample types included vulvovaginal/endocervical or urethral swabs (dry swab or eSwab®), semen and urine samples, which included blinded analysis following addition of a panel of 80 characterized control strains.

RESULTS

Overall species identification was excellent for both Ureaplasma spp. (98.4% sensitivity, 99.7% specificity) and M. hominis (95.7% sensitivity, 100% specificity) relative to combined colony morphology on agar and quantitative PCR standards. Non-dilution-based bacterial load estimation by the assay was accurate between 83.7% (M. hominis) and 86.3% (Ureaplasma spp.) of the time (increased to 94.2% and 100%, respectively, if ±10-fold variance was allowed) relative to colonies counted on agar. Resistance accuracy for Ureaplasma spp. varied from gold standards for only 11/605 of individual tests (major error rate = 1.8%) and for 14/917 individual tests for M. hominis (major error rate = 1.5%).

CONCLUSIONS

The redesigned MYCOPLASMA IST3 assay eliminated previous shortcomings by providing independent accurate resistance screening of M. hominis and Ureaplasma species, even in mixed infections, with CLSI-compliant thresholds. Specificity, sensitivity and enumeration estimates correlated closely with the confirmatory methods.

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.

Mycoplasma hominis: An under recognized pathogen

Mycoplasma hominis, a commensal of the genital tract, is a potential underestimated pathogen causing both genitourinary and extragenital infections including neonatal infections. Septic arthritis, prosthetic joint infection, central nervous system (CNS) infections, infective endocarditis and abscess formation are common extragenital infections associated mainly with immunocompromised patients. Mycoplasma hominis lipoproteins play an important role in pathogenicity and directly interact with the host immune system. Polymerase chain reaction (PCR) is the mainstay of diagnosis. Increasing resistance to tetracyclines and quinolones which are used for treatment, is a matter of global concern. We reviewed PubMed literature and Google search engine on the recent developments of association of Mycoplasma hominis with various diseases, pathogenesis, diagnosis and treatment.

Examination of Ureaplasma urealyticum and Mycoplasma hominis in 4082 Chinese patients

The objective of this study was to analyze the infection rate and drug resistance of Ureaplasma urealyticum (UU) and Mycoplasma hominis (MH) in the genitourinary tract of Chinese patients. From December 2018 to June 2019, vaginal secretion or urinary secretion of outpatients in our hospital were selected for culture and drug sensitivity analysis of Ureaplasma urealyticum and Mycoplasma hominis. In 4082 Chinese samples, 1567 Mycoplasma were detected, a detection rate of 38.39%, among which 1366 cases were UU single positive, accounting for 33.47%, 15 cases were MH single positive, accounting for 0.36%, 186 cases were UU and MH mixed positive, accounting for 4.56%. The most affected age groups were 21-30 years and 31-40 years, accounting for 19.09 and 15.05%, respectively. The results of drug sensitivity showed that doxycycline, minocycline, josamycin, clarithromycin, and roxithromycin were more sensitive to mycoplasma infection. The distribution of Ureaplasma urealyticum and Mycoplasma hominis in the human genitourinary system and their sensitivity to antibiotics is different for sex and age groups.

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

This study aimed to study the antimicrobial resistance, genetic characterization, and molecular epidemiology of Ureaplasma species in order to provide clinicians sufficient data to select optimal strategies of treatment for genitourinary tract infections of infertile male patients. Firstly, a total of 817 clinical semen specimens were detected for Ureaplasma species by molecular detection. Secondly, culture and identification of Ureaplasma species were achieved by using Mycoplasma ICS Test, and the antimicrobial susceptibility tests were determined by using broth microdilution assay. Then, the tetracycline resistance genetic determinants in Ureaplasma species were identified by PCR, and the fluoroquinolone and macrolide resistance genetic determinants were identified by DNA sequencing. Finally, the molecular epidemiology of Ureaplasma species was studied by both multilocus sequence typing (MLST) and expanded MLST (eMLST) schemes. Among the 817 semen specimens, 320 (39.17%) specimens were positive for Ureaplasma species. The percentages of resistance in 320 isolates against LEV, MXF, TET, and ERY were 47.5%, 39.38%, 19.69%, and 3.75%, respectively. The tet(M) and int-Tn genes were detected positive in all the tetracycline-resistant isolates. One macrolide-resistant UU isolate had a novel amino acid alteration (R66T) in L4 ribosomal protein and another UU isolate harbored a novel alteration (S109T) in L22. In fluoroquinolone-resistant isolates, S83L substitution in the ParC was predominant. In this area, ST22 and eST16 were the most prevalent ST and eST, respectively. One ST and 3 eSTs were newly identified in this study. This study has demonstrated that ERY can be first-line therapy for Ureaplasma species infections.