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Objective: This study evaluated Staphylococcus aureus adhesion and biofilm formation on vascular grafts, which has seldom been investigated., Methods: Adhesion and biofilm formation capabilities of three methicillin susceptible S. aureus strains (one biofilm forming reference strain and two clinical isolates) on five different vascular biomaterials were evaluated in vitro, including polyester (P), P + gelatin (PG), P + collagen (PC), PC + silver (PCS), and PCS + triclosan (PCST). Staphylococcus aureus adhesion on grafts was evaluated after one hour of culture and biofilm formation after 24 hours of culture by four different methods: spectrophotometry after crystal violet staining; sonicate fluid culture; metabolic assay; and scanning electron microscopy (SEM). Optical density was compared using Mann-Whitney pairwise test, and bacterial counts using Wilcoxon pairwise test., Results: PCST grafts were most efficient in preventing S. aureus adhesion and biofilm formation, regardless of the method used. Bacterial counts and metabolic activity were significantly lower on PCST grafts after 24 hours (5.65 vs. 9.24 [PCS], 8.99 [PC], 8.82 [PG], and 10.44 log 10 CFU/mL [P]; p < .015), and only PCST grafts were bactericidal. Biofilm formation was significantly diminished on PCST grafts compared with all other grafts (p < .001). Bacterial viability and metabolic activity after 24 hours were more impaired on PG compared with PC graft, and were surprisingly higher on PCS compared with PC grafts. Biofilm biomass formed after exposure to P, PG, PC, and PCS grafts was also reduced after 24 hours of incubation with PCST grafts (p < .001). After 24 hours, few bacteria were visible by SEM on PCST grafts, whereas bacterial biofilm colonies were clearly identified on other graft surfaces., Conclusion: Triclosan impregnated PCST grafts appeared to interfere with S. aureus adhesion from early stages of biofilm formation in vitro. Silver impregnation was not efficient in preventing biofilm formation, and collagen coating promoted S. aureus biofilm formation more than gelatin coating., (Copyright © 2023 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.)

Objectives: We evaluated the clinical performances of four multiplex real-time PCR commercial kits for the detection of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium and Trichomonas vaginalis: the STI PLUS ELITe MGB kit (ELITechGroup), N. gonorrhoeae/C. trachomatis/M. genitalium/T.vaginalis Real-TM kit (Sacace Biotechnologies), Allplex STI Essential kit (Seegene), and FTD Urethritis Plus kit (Fast-Track Diagnostics)., Methods: The kit performance for C. trachomatis, N. gonorrhoeae, M. genitalium and T. vaginalis detection was compared to that of the cobas CT/NG and TV/MG kits (Roche Diagnostics) using 425 samples, mainly urine and cervicovaginal, throat and rectal swabs. Detection of Ureaplasma parvum, U. urealyticum and Mycoplasma hominis were compared to that of in-house TaqMan PCRs., Results: The four kits showed good performances for the detection of C. trachomatis. They all presented a low positive agreement for the detection of M. genitalium and T. vaginalis (ranges 63.3-74.1% and 51.2-68.4%, respectively) compared to the cobas MG/TV kit. The Seegene and Sacace kits showed additional low positive agreement for the detection of N. gonorrhoeae (71.2%, 95%CI 61.8-79.0 and 63.1%, 95%CI 53.5-71.8, respectively). We observed a slight but significant lower negative agreement for N. gonorrhoeae detection using the ELITechGroup kit (92.5%, 89.1-94.9) and for M. genitalium detection using the Fast-Track kit (93.2%, 89.6-95.7) compared to other kits., Conclusion: Multiplex real-time PCR kits are convenient methods for the detection of several pathogens associated with sexually transmitted infections (STIs) in a single step, but colonizing Ureaplasma spp. and M. hominis species should not be included in these kits. Users should be aware of the weak performance of some kits for the detection of M. genitalium and T. vaginalis., (Copyright © 2021 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Objectives: Limited data on Mycoplasma genitalium infection has been reported among PrEP users. The aim of this study was to estimate the prevalence and macrolide resistance of M. genitalium infection among enrollees in a French PrEP program., Patients and Methods: M. genitalium infection screening was systematically and prospectively proposed to patients of the Bordeaux PrEP program (between January 2016 and February 2017). Macrolide resistance was evaluated in M. genitalium-positive patients., Results: Among 89 clients, M. genitalium infection prevalence was 10% (mainly asymptomatic) with a high rate of macrolide resistance (58%)., Conclusions: Because of a high level of macrolide resistance, a systematic search for M. genitalium macrolide resistance associated-mutations may be recommended in PrEP users before initiating the antibiotic therapy., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

We report the case of a Ureaplasma parvum meningitis in an immunocompetent patient, 17 days after surgical ablation of a craniopharyngioma. Presence of U. parvum in the cerebrospinal fluid was assessed by 16S rDNA sequencing and U. parvum specific PCR. This article details a surprising complication in an adult of a transphenoidal surgery for ablation of a craniopharyngioma. This is the first case, to our knowledge, of U. parvum meningitis in an adult patient., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objectives: Prosthetic vascular graft infections (PVGIs) are associated with high mortality rates. To improve treatment outcome, an early and definite diagnosis is critical, and current diagnostic criteria are often insufficient. The accuracy of 2-deoxy-2-[fluorine-18]-fluoro-d-glucose positron emission tomography integrated with computed tomography ( 18 F-FDG PET/CT) and white blood cell (WBC) scan for the diagnosis of PVGI were compared., Methods: A retrospective single centre study was conducted on patients undergoing WBC scan and 18 F-FDG PET/CT for a suspected PVGI between April 2013 and June 2016 at the Bordeaux University Hospital, France. The diagnostic value of both imaging tests was assessed for all grafts, using receiver operating characteristic (ROC) curve analysis. Images were independently interpreted by two nuclear medicine physicians blinded to the patients' clinical and other imaging data., Results: Thirty-nine patients were included, of whom 15 had PVGI. Antibiotic treatment was started before nuclear imaging for 16 patients, including nine patients with a PVGI. The 96 grafts of these patients were analysed, and 19 were infected. The diagnostic value of the WBC scan was significantly higher than 18 F-FDG PET/CT (ROC AUC = 0.902, 95% CI 0.824-0.980, and 0.759, CI 95% (0.659-0.858), respectively, p = .0071). Interobserver agreement was good for 18 F-FDG PET/CT and excellent for WBC scan (kappa value of 0.76, 95% CI 0.62-0.9, and 0.97, 95% CI 0.92-1, respectively). Only one patient had a false negative 18 F-FDG PET/CT result under antibiotic therapy., Conclusion: The WBC scan has a better diagnostic value than 18 F-FDG PET/CT for PVGI diagnosis., (Copyright © 2019 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.)

Objectives: The aim was to compare the antimicrobial efficacy of four different grafts: a standard graft (Intergard, IG), an IG graft soaked in rifampicin (IGrif), a silver impregnated graft (Intergard Silver, IGS), and a silver + triclosan impregnated graft (Intergard Synergy, IGSy)., Methods: This was a seven day in vitro study. The IG, IGrif, IGS, and IGSy grafts were each contaminated separately with the following microorganisms: Staphylococcus epidermidis, Methicillin resistant Staphylococcus aureus (MRSA), Escherichia coli, and Candida albicans from both clinical and American Type Culture Collection (ATCC) origins. The in vitro antimicrobial efficacy was evaluated by time to kill assays at T0, T24h, T48h, T72h, and T168h. Bactericidal activity was defined as >3 log 10 reduction factor (logRF). Additionally, Rifampicin, triclosan and silver resistance development were screened., Results: As anticipated for the non-antimicrobial IG, all microorganism strains proliferated. The IGSy and the IGS showed a seven day bactericidal efficacy (>3 logRF) for all tested microorganisms. This efficacy was confirmed at all time points for IGSy only, demonstrating faster bactericidal efficacy than IGS. The IGrif demonstrated a seven day bactericidal efficacy against the ATCC MRSA only, while showing no activity against C. albicans and ATCC E. coli. Regarding ATCC S. epidermidis, clinical MRSA and clinical E. coli, IGrif, although bactericidal at earlier time points, lost its antimicrobial efficacy at seven days leading to the emergence of rifampicin resistant mutants in four of six, two of six, and two of six assays, respectively. Mutant strains were also detected in ATCC MRSA in one of six assays. No triclosan or silver resistance has emerged at T7days., Conclusion: For all microorganisms tested, the Synergy graft combining silver with triclosan demonstrated a more sustainable and efficient seven day antimicrobial activity than the rifampicin soaked graft. The emergence of rifampicin resistant mutants suggests preference for a Synergy graft over a graft soaked in rifampicin, to prevent or treat an infection when a biological solution is not feasible., (Copyright © 2018 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.)

Objectives: Vascular graft infections (VGIs) are severe and require prolonged adequate antimicrobial therapy. However, up to 45% of conventional cultures are negative. Sonication and genus specific PCRs for microbiological diagnosis of VGI was evaluated., Methods: Samples were prospectively obtained from explanted vascular grafts in Bordeaux University Hospital. Conventional bacterial cultures with and without prior sonication of samples were performed. A genus specific PCR assay panel, targeting the most frequent bacteria involved in VGI (Staphylococcus, Streptococcus, Enterococcus, and Enterobacteriaceae), was also applied to sonicate fluids. The performance of these three diagnostic strategies was compared., Results: Forty-five patients (118 samples) were included between July 2014 and October 2015. Six patients had no infection and 39 had a VGI. Sensitivities of graft culture, sonicate fluid culture, and genus specific PCR were 85.7%, 89.7%, and 79.5%, respectively. Specificities were 100%, 100%, and 83.3%, respectively. Sonicate fluid culture was positive for five graft samples (from four patients) with negative culture without sonication. Four VGIs were detected by PCR only (3 patients had previously received antibiotics). For 15 patients with positive graft cultures, PCR identified at least one additional bacterium compared with culture, thus 30 additional bacteria for all included patients. By combining sonicate fluid culture and PCR, a microbiological diagnosis was obtained for all patients with VGI., Conclusions: There was no statistical difference between performances of culture with and without sonication and genus specific PCR. However, combining sonicate fluid cultures and PCR may be the best strategy for microbiological diagnostic of VGI., (Copyright © 2018 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.)

Objective: Mycoplasma genitalium and Trichomonas vaginalis are common causes of sexually transmitted infections, but limited prevalence data are available in France. We aimed to evaluate the prevalence of M. genitalium and T. vaginalis infections and to assess prevalence by gender, age, sample collection sites and clinical symptoms. A multicentre collection of specimens was intended to obtain a nationwide overview of the epidemiology., Methods: Between September 2014 and January 2015, a total of 2652 consecutive urogenital specimens submitted to the microbiology diagnostic departments of 16 French university hospitals for Chlamydia trachomatis and Neisseria gonorrhoeae detection were collected. M. genitalium and T. vaginalis prevalence were evaluated using a commercial real-time PCR kit. Clinical data from patients were anonymously collected., Results: T. vaginalis and M. genitalium prevalence were 1.7% (95% confidence interval 1.3-2.4) and 3.4% (95% confidence interval 2.8-4.2), respectively, and did not differ between gender or age groups, except M. genitalium prevalence between men and women in the 35- to 44-year age group (5.9 vs. 1.5%; p 0.03). M. genitalium prevalence was significantly higher in patients receiving care in sexually transmitted infection clinics, abortion centres, family planning clinics and prisons than in gynaecologic, obstetric and reproduction centres (4.0 vs. 1.7%, p 0.009). Among M. genitalium- and T. vaginalis-positive patients, 70.9 and 61.5% were asymptomatic, respectively., Conclusions: The low T. vaginalis prevalence does not justify systematic screening for this organism in France. Conversely, selective screening for M. genitalium may be warranted in care settings that receive presumably high-risk sexual behaviour patients, regardless of symptoms., (Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Meningitis due to Mycoplasma hominis in adults is rarely described, with only three cases having been reported to date. A case of fatal meningitis in a 39-year-old patient after a neurosurgical procedure for a subarachnoid haemorrhage is reported herein. Identification and treatment were significantly delayed because of the rarity of the aetiology and difficulty identifying this organism with the routinely used conventional methods, such as Gram staining and agar growth on standard agar plates. Clinical procedures and the treatment of 'culture-negative' central nervous system infections is a real challenge for clinical microbiologists and clinicians, and M. hominis has to be considered as a potential, although very uncommon, pathogen., (Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Objectives: The aim was to compare the antimicrobial efficacy of the silver impregnated collagen coated polyester vascular graft (IGS) with an identical graft combining silver and triclosan (IGSy)., Methods: This was an in vitro study. A non-antimicrobial collagen polyester vascular graft served as control (IG). The IG, IGS, and IGSy grafts were contaminated separately with inoculates of each of the following micro-organisms: Staphylococcus epidermidis (SE), methicillin resistant Staphylococcus aureus (MRSA), and Escherichia coli producing extended spectrum beta-lactamase (ESBL-EC) or Candida albicans (CA). MRSA, ESBL-EC, and CA were obtained from retrieved infected grafts. The in vitro antimicrobial efficacies of the contaminated grafts were evaluated by time to kill assays over a 24 hour period in accordance with CLSI Guideline M26-A. All assays were repeated six times. Bacterial survival numbers were obtained at 1, 4, 8, and 24 hours using a standard plate count procedure. Bactericidal activity was defined as a 3 log10 reduction factor (logRF). To calculate the overall difference in the mean log10 CFU/mL within 24 hours, a one way ANOVA with a Bonferroni correction was calculated separately for each graft., Results: The IG graft showed an increase in the number of viable organisms for the four strains tested. IGSy offered better antimicrobial properties than IGS for both ESBL-EC and MRSA, since only the IGSy graft achieved > 3 logRF and fulfilled the standard criteria for bactericidal activity at 24 hours with 3.78 and 4.08 logRF, respectively. For samples inoculated with SE and CA, both antimicrobial grafts achieved 24 hour bactericidal activity with > 3 logRF. However, for CA the one-way ANOVA analysis demonstrated that the IGSy graft performed differently in terms of speed of antimicrobial action, appearing more active as early as 4 hours following inoculation (p = .007)., Conclusion: In the in vitro conditions, the Synergy vascular graft combining silver with triclosan demonstrated better short-term antimicrobial activity than the silver graft for all micro-organisms tested., (Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

Diagnosis of prosthetic vascular graft infection (PVGI) is a clinical challenge requiring accurate diagnostic methods for their optimal management. A 65-year-old patient with suspected PVGI was explored by fluorodeoxyglucose positron emission tomography combined with computed tomography ((18)F-FDG PET-CT) for pretreatment staging. Standard imaging was unrevealing but PET images showed multiple foci with increased uptake suggesting prosthetic infection. While routine results from the diagnostic laboratory were negative, prosthesis sonication before standard culture revealed the same bacterium as a culture of preoperative lymphocele aspiration. (18)F-FDG PET-CT and preliminary sonication of the prosthetic graft could be very helpful in the diagnosis of PVGI especially for highlighting biofilm bacteria., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Typing of Mycoplasma pneumoniae by multiple-locus variable-number tandem repeat analysis (MLVA) is increasingly in use. However, no specific internationally agreed guidance is available. Thirty M. pneumoniae DNA samples including serial dilutions of a type strain were sent to six international laboratories to perform MLVA and results were compared. Good correlation was observed, indicating that this methodology can be robustly performed in multiple sites. However, differences due to interpretation of fragment size, repeat sequence identification and repeat numbering led to inconsistency in the final profiles assigned by laboratories. We propose guidelines for interpreting M. pneumoniae MLVA typing and assigning the number of repeats.

An increased incidence of Mycoplasma pneumoniae infections was reported in 2011 in two cities in France, Bordeaux and Caen. Two complementary molecular typing methods, PCR-RFLP on adhesin P1 and multilocus variable number tandem repeat analysis (MLVA), were used to determine whether this phenomenon was clonal. In 2011, the percentage of M. pneumoniae-positive patients doubled in both cities compared with 2010. Macrolide resistance remained stable at 8.3% of patients. Eighteen MLVA types were identified among 94 M. pneumoniae-positive specimens, demonstrating that the phenomenon was multiclonal. Types P, J, U, X and E were the most frequent and 81.6% of the strains were adhesin P1 type 1., (© 2012 The Authors Clinical Microbiology and Infection © 2012 European Society of Clinical Microbiology and Infectious Diseases.)

Mycoplasma hominis is an opportunistic human mycoplasma species that can be either commensal or pathogenic. Its detection by culture is considered to comprise the reference technique. Previously reported PCR techniques target the 16S rRNA or the gap gene, although sequence variations among clinical isolates may lead to variations in clinical sensitivity. The present study aimed to develop a specific TaqMan quantitative real-time PCR assay, targeting a gene conserved in all M. hominis isolates, and to compare it with quantitative culture. With the knowledge of the M. hominis PG21 genome sequence, the yidC gene, encoding a membrane protein translocase, was chosen as target. Its intraspecies heterogeneity was checked at the nucleotide level using 31 reference or clinical strains. The limit of detection, the analytical specificity and the reproducibility of the assay were assessed. Moreover, PCR and culture results were compared using 153 urogenital specimens. The limit of detection was seven copies/μL. The analytical specificity was 100%, with good inter- and intra-assay reproducibility. Among the 153 urogenital specimens, the yidC PCR and culture allowed detection of 55 and 45 M. hominis-positive samples, respectively. Comparison of the bacterial load among the 45 specimens found to be M. hominis-positive by both techniques revealed a statistically significant association between the quantitative results obtained. In conclusion, we developed a specific, sensitive and reproducible real-time PCR to detect all M. hominis clinical isolates. This PCR was shown to have higher sensitivity than culture, although both methods were correlated for quantification of M. hominis loads in urogenital specimens., (© 2010 The Authors. Journal Compilation © 2010 European Society of Clinical Microbiology and Infectious Diseases.)

Three isolates of Mycoplasma amphoriforme, a new Mycoplasma species rarely described to date, were obtained from respiratory tract specimens from two children and one adult with respiratory tract infections. Molecular methods were required to distinguish them from Mycoplasma pneumoniae. MICs of macrolides, tetracyclines and fluoroquinolones were identical to those for M. pneumoniae, except for that of ciprofloxacin, which was slightly more potent against M. amphoriforme. M. amphoriforme could possibly have been involved in one case of severe respiratory infection with sepsis, but further studies are needed to specify its role as a potential respiratory tract pathogen.

The activity of moxifloxacin was compared with that of other antimicrobial agents against 54 strains of Ureaplasma spp., 54 strains of Mycoplasma hominis, 14 strains of Mycoplasma genitalium, and 44 strains of Chlamydia trachomatis. Moxifloxacin inhibited 90% of all isolates at a concentration

Human pasteurellosis is, in general, a locoregional infection due to contact with an animal. Systemic infections are rare and endocarditis is exceptionally described. The authors report two new cases of endocarditis due to Pasteurella spp, they then review 29 other published cases. Pasteurella spp. endocarditis presents as an acute form in 64% of cases and affects the aortic as often as the mitral valves. Contact with an animal is documented in 65% of cases. Pasteurella multocida is the most frequent species in this infection. The total death rate is 40% and can reach 57% of cases in case of immunodepression. The bad prognosis of this infection, justifies an early diagnosis and a rapid and adapted but not yet consensual medicosurgical treatment.