This study evaluates the in vitro activity of five clinically-relevant β-lactam antibiotics against 158 Enterococcus faecalis clinical isolates from France and assesses whether ampicillin (AMP) disc diffusion can predict susceptibility. No β-lactamase-producing strains were detected and 100

OBJECTIVES:To assess the epidemiological susceptibility distribution of five β-lactam antibiotics for contemporary clinical isolates of non-faecalis Enterococcus species categorized as susceptible to ampicillin and to evaluate the performance of gradient diffusion (GD) tests compared to broth microdilution (BMD), the reference method for antimicrobial susceptibility testing. METHODS:A total of 455 non-duplicate non-Enterococcus faecalis clinical isolates reported as ampicillin susceptible were collected from 43 French hospital laboratories. Identification to the species level was performed using MALDI-TOF mass spectrometry. MICs of amoxicillin, piperacillin, imipenem, meropenem and ceftobiprole were determined by BMD and GD. Results were interpreted according to the 2025 EUCAST recommendations. Agreement between GD and BMD was assessed using ISO and FDA criteria. RESULTS:All isolates were susceptible to amoxicillin, 94% (428/455) to ceftobiprole, 88% (401/455) to imipenem at high dose and 88% (402/455) to piperacillin. Enterococcus casseliflavus displayed the lowest MIC values across all β-lactams, followed by Enterococcus avium. In contrast, Enterococcus faecium, Enterococcus lactis, Enterococcus gallinarum and Enterococcus hirae exhibited right-shifted MIC distributions. Most species showed high MICs for meropenem, indicating low intrinsic activity. GD methods did not achieve FDA or ISO criteria for most species-antibiotic combinations. CONCLUSIONS:Overall, ampicillin may predict amoxicillin categorization for frequent non-faecalis enterococci, and with the exception of meropenem, most β-lactams may still have clinical value against these species. The different species exhibit distinct MIC distribution patterns for the tested β-lactams. Furthermore, substantial discrepancies observed between GD and BMD methods highlight the limited reliability of GD as an alternative to BMD.

BACKGROUND:Nontuberculous mycobacterial (NTM) adenitis is increasingly recognized in children; however, optimal management strategies remain debated. The aim of this study was to describe the clinical characteristics, management and outcomes of pediatric NTM lymphadenitis in France. METHODS:We conducted a multicenter retrospective descriptive study of culture-confirmed NTM lymphadenitis cases in children across 15 French hospitals participating in the MYCOMED network between 2010 and 2019. RESULTS:A total of 279 patients were included, with a progressive increase in diagnoses over the study period, from 11 cases in 2010 to 33 in 2019, with peaks of 38 observed in 2015 and 2018. Most patients were female (64%) with a median age of 3 years. Mycobacterium avium was the most frequently isolated species (71%). Histologic examination revealed necrotizing granulomatous lymphadenitis in two-third of cases (71%, 112/115), and acid-fast bacilli staining was positive in 24.6% (68/276) of the cases. Of the 250 patients with available therapeutic data, 34.8% were treated with surgery alone, 24.8% with antibiotics alone, 28% with combined therapy and 12.4% received no treatment. Overall, 104 children were lost to follow-up. Among 175 patients with follow-up data, the overall cure rate was 96%, with no significant differences between therapeutic strategies. Relapse occurred in 6 children (3.4%). No cases of facial nerve palsy were reported; however, cosmetic sequelae related to scarring were observed. CONCLUSIONS:The incidence of pediatric NTM adenitis has increased over the last decade in France, with M. avium as the predominant species. The clinical outcome was favorable in most cases, irrespective of the management strategy. Surgery with complete excision should be considered when technically feasible and safe, while antibiotics or a "wait and see" strategy remain acceptable alternatives.

AIM:The aim of this study was to describe the bacterial epidemiology and antibiotic resistance rates of bacterial isolates collected from urine specimens in male patients with suspected urinary tract infection (UTI). METHODS:This retrospective multicenter study included routine data from midstream urine cultures of adult male patients with suspected UTI admitted to the emergency departments of 15 hospitals from 2019 to 2023. Urinalysis was performed according to the recommendations of the French Society for Microbiology and bacterial identification was carried out using MALDI-TOF mass spectrometry. Antimicrobial susceptibility testing was performed by disk diffusion or semi-automated methods and interpreted according to the CA-SFM/EUCAST guidelines. RESULTS:Overall, 38,279 bacterial isolates were detected among 33,113 male patients (mean age = 70.7 years). The most frequently encountered pathogen was E. coli (40.0 %) followed by E. faecalis (13.2 %), K. pneumoniae (7.8 %) and P. mirabilis (5.8 %). Overall prevalence of ESBL-E was 9.0 %, represented mainly by K. pneumoniae (22.8 %), E. cloacae complex (19.3 %) and E. coli (8.4 %). Prevalence of resistance to fluoroquinolones and cotrimoxazole was high (usually > 15-20 %). The resistance rates in E. coli were very low (around 1 %) for fosfomycin and nitrofurantoin, as was the overall prevalence of carbapenemase-producing Enterobacterales (0.1 %). In S. aureus, 20.4 % of isolates were resistant to methicillin, and only three vancomycin-resistant enterococci (<0.01 %) were detected. CONCLUSION:This original study provides recent, nationwide and helpful data on bacterial epidemiology and antibiotic resistance rates of isolates recovered from urines in male patients with suspected UTIs.

Ceftobiprole (CBP) is an anti-methicillin-resistant Staphylococcus aureus (MRSA) cephalosporin with a wide spectrum of activity. We aimed to describe our experience of real-life use of CBP for the treatment of severe infections of critically ill patients with multiple infected sites and related trough CBP concentrations. We performed a retrospective, observational, monocentric study in our intensive care unit (ICU) that included all patients treated with CBP for documented infections between January 2016 and December 2021. We collected demographic, clinical, and microbiological data. When available, we report the CBP trough concentrations. The primary endpoint was clinical cure at the end of treatment. The secondary endpoints were in-hospital mortality and documentation of the carriage of multidrug-resistant (MDR) bacteria not present before CBP treatment. Between January 2016 and December 2021, 47 patients were treated in the ICU with CBP. The main indication for treatment was pneumonia (51%) and most patients presented with associated bacteremia (72%). All infections were polymicrobial. A clinical cure was achieved for nearly 80% of the patients. Only five patients presented new carriage of MDR bacteria. In-hospital mortality was 32%. Out of 21 strains of Enterobacterales for which the MIC was available, 33% were considered to be resistant to CBP according to the EUCAST 2023 clinical breakpoint. Trough CBP concentrations were reported for 16 patients. In our real-life experience, treatment of ICU patients with CBP for polymicrobial severe infections resulted in most cases in a clinical cure. Monitoring of trough concentrations is critical, especially in cases of high MIC.

Background: The incidence of Enterococcus faecalis infective endocarditis is increasing over time. Data on the impact of minimum inhibitory concentration (MIC) of amoxicillin on treatment outcomes are scarce. The objective of this study was to describe the epidemiology of E. faecalis infective endocarditis and to evaluate whether the MIC of amoxicillin might influence mortality. Materials: We retrospectively included all consecutive patients diagnosed with definite E. faecalis infective endocarditis between 2013 and 2020 in 11 French hospitals. We extracted data from the local diagnosis-related group (DRG) database and matched these data with microbiologicalresults. Amoxicillin MIC was determined by Etest strip. The primary endpoints were endocarditis-related mortality and risk factors for endocarditis-related mortality including amoxicillin MIC. Results: A total of 403 patients with definite E. faecalis infective endocarditis were included. Patients were predominantly male (76.4%) with a median age of 74 years (67-82). Embolic complications occurred in 170 (42.1%) patients. Cardiac surgery was performed in 158 (61.5%) patients. The endocarditis-related mortality rate was 28.3% and the median delay between mortality and onset of hospitalization was 24 (9; 41) days. E. faecalis MIC of amoxicillin was available for 246 (61%) patients. The median MIC was 0.5 mg/L (0.4-0.7). Amoxicillin MIC was not found to be associated with in-hospital mortality. None of the variables included in the multivariate model were identified as a risk factor for mortality and there was no correlation between mortality and the duration of treatment for 4 weeks versus 6 weeks. Conclusions: Higher amoxicillin MIC was not a risk factorleading to endocarditis-related mortality in definite E. faecalis infective endocarditis. However, further studies are needed to assess the effect of amoxicillin MIC on relapse.

Objectives: Ceftolozane-tazobactam (C/T) proved its efficacy for the treatment of infections caused by non-carbapenemase producing Pseudomonas aeruginosa and Enterobacterales. Here, we aimed to provide susceptibility data on a large series of Enterobacterales since the revision of EUCAST categorization break-points in 2020.Methods: First, C/T susceptibility was determined on characterized Enterobacterales resistant to third generation cephalosporins (3GCs) (extended spectrum beta-lactamase [ESBL] production or different levels of AmpC overexpression) (n = 213) and carbapenem-resistant Enterobacterales (CRE) (n = 259), includ-ing 170 carbapenemase producers (CPE). Then, 1632 consecutive clinical Enterobacterales responsible for infection were prospectively collected in 23 French hospitals. C/T susceptibility was determined by E -test (R) (biomerieux) and broth microdilution (BMD) (SensititreTM, Thermo Scientific) to perform method comparison.Results: Within the collection isolates, 88% of 3GC resistant strains were susceptible to C/T, with impor-tant variation depending on the resistance mechanism: 93% vs. 13% susceptibility for CTX-M and SHV-ESBL producers, respectively. Only 20% of the CRE were susceptible to C/T. Among CPE, 80% of OXA-48-like producers were susceptible to C/T, whereas all metallo-,B-lactamase producers were resistant. The prospective study revealed that 95.6% of clinical isolates were susceptible to C/T. Method comparison performed on these 1632 clinical isolates demonstrated 99% of categorization agreement between MIC to C/T determined by E-test (R) in comparison with the BMD (reference) and only 74% of essential agreement. Conclusion: Overall, C/T showed good activity against wild-type Enterobacterales, AmpC producers, and ESBL-producing Escherichia coli but is less active against ESBL-producing Klebsiella pneumoniae, and CRE. E-test (R) led to an underestimation of the MICs in comparison to the BMD reference.(c) 2023 The Author(s). Published by Elsevier Ltd on behalf of International Society for Antimicrobial Chemotherapy.This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )

Achromobacter spp. are nonfermenting Gram-negative bacilli mainly studied among cystic fibrosis (CF) patients. The identification of the 19 species within the genus is time-consuming (nrdA-sequencing), thus data concerning the distribution of the species are limited to specific studies. Recently, we built a database using MALDI-TOF mass spectrometry (MS) (Bruker) that allows rapid and accurate species identification and detection of the multiresistant epidemic clones: A xylosoxidans ST137 spreading among CF patients in various French and Belgium centers, and A. ruhlandii DES in Denmark. Here, we first assessed whether species identification could be achieved with our database solely by analysis of MS spectra without availability of isolates. Then, we conducted a multicentric study describing the distribution of Achromobacter species and of the clone ST137 among French CF centers. We collected and analyzed with our local database the spectra of Achromobacter isolates from 193 patients (528 samples) from 12 centers during 2020. In total, our approach enabled to conclude for 502/528 samples (95.1%), corresponding to 181 patients. Eleven species were detected, only five being involved in chronic colonization, A. xylosoxidans (86.4%), A. insuavis (9.1%), A. mucicolens (2.3%), A. marplatensis (1.1%) and A. genogroup 3 (1.1%). This study confirmed the high prevalence of A. xylosoxidans in chronic colonizations and the circulation of the clone A. xylosoxidans ST137 in France: four patients in two centers. The present study is the first to report the distribution of Achromobacter species from CF patients samples using retrospective MALDI-TOF/MS data. This easy approach could enable future large-scale epidemiological studies.

Although Candida spp are aerobic microorganisms, some Candida strains, mainly Candida glabrata, can be recovered from anaerobic blood culture vials. We assessed the contribution of the anaerobic vials for the diagnosis of candidemia, especially for C. glabrata. We conducted a multicenter retrospective study including eight university or regional hospitals. A single episode of monomicrobial candidemia per patient was included from September 1st, 2016, to August 31st, 2019. The characteristics of all aerobic and anaerobic blood culture vials sampled within 2 h before and after the first positive blood culture vials were recorded (type of vials, result, and for positive vials time-to-positivity and Candida species). Overall, 509 episodes of candidemia were included. The main species were C. albicans (55.6%) followed by C. glabrata (17.1%), C. parapsilosis (4.9%), and C. tropicalis (4.5%). An anaerobic vial was positive in 76 (14.9%) of all episodes of which 56 (73.8%) were due to C. glabrata. The number of C. glabrata infections only positive in anaerobic vials was 1 (2.6%), 1 (11.1%), and 15 (37.5%) with the BACT/ALERT 3D the BACT/ALERT VIRTUO and the BACTEC FX instrument, respectively (P < 0.01). The initial positivity of an anaerobic vial was highly predictive of the isolation of C. glabrata with the BACTEC FX (sensitivity of 96.8%). C. glabrata time-to-positivity was shorter in anaerobic vial than aerobic vial with all instruments. Anaerobic blood culture vials improve the recovery of Candida spp mainly C. glabrata. This study could be completed by further analyses including mycological and pediatric vials. LAY SUMMARY:Although Candida spp are aerobic microorganisms, C. glabrata is able to grow in anaerobic conditions. In blood culture, the time-to-positivity of C. glabrata is shorter in anaerobic than aerobic vials. Only the anaerobic vial was positive in up to 15 (37.5%) C. glabrata bloodstream infections.

Zoonotic species of Capnocytophaga genus belong to the oral microbiota of dogs and cats. They may be responsible for serious human infections, mainly after animal bites, with a high mortality rate. In France, only few cases have been reported and no multicenter study has been conducted. Our aim was to describe the French epidemiology of Capnocytophaga zoonosis. We conducted a multicenter (21 centers) retrospective non-interventional, observational study in France describing the epidemiology of Capnocytophaga zoonosis (C. canimorsus, C. cynodegmi, C. canis) over 10 years with regard to clinical and bacteriological data. From 2009 to 2018, 44 cases of Capnocytophaga zoonotic infections were described (C. canimorsus, n = 41; C. cynodegmi, n = 3). We observed an increase (2.5 times) in the number of cases over the study period (from the first to the last 5 years of the study). The most frequent clinical presentations were sepsis (n = 37), skin and soft tissue infections (n = 12), meningitis (n = 8), osteoarticular infections (n = 6), and endocarditis (n = 2). About one-third of patients with sepsis went into septic shock. Mortality rate was 11%. Mortality and meningitis rates were significantly higher for alcoholic patients (p = 0.044 and p = 0.006, respectively). Other comorbidities included smoking, splenectomy, diabetes mellitus, and immunosuppressive therapy are associated to zoonotic Capnocytophaga infection. Eighty-two percent of cases involved contact with dogs, mostly included bites (63%). Despite all isolates were susceptible to the amoxicillin-clavulanic acid combination, three of them were resistant to amoxicillin.

Microbiological diagnosis of osteoarticular infections (OAls) is based on culture on several media. Experts recommend the use of liquid media, such as Schaedler broth, but many laboratories use blood culture media with automated detection instead for convenience. We aimed to evaluate the performance of culturing in BacT/Alert (bioMerieux) bottles for the microbiological diagnosis of OAI versus culturing in Schaedler broth. This prospective study was conducted on all osteoarticular specimens sent to the microbiology laboratories of the Versailles and Diaconesses Croix Saint-Simon hospitals between October 2016 and February 2017. Each sample was inoculated onto solid agar, into BacT/Alert bottles incubated for 14 days, and into a Schaedler broth incubated for 14 days with daily reading. The gold standard was defined as follow: OAI was diagnosed for a patient if at least two samples were positive for a nonskin microorganism and at least three for a cutaneous species. The times to detection were compared. A total of 1,616 specimens from 349 patients were collected. BacT/Alert bottles were significantly more sensitive than the Schaedler process for OAI diagnosis (114/135 OAI detected by BacT/Alert bottles; 91/135 OAI detected by Schaedler broth; +17.0% (95% confidence interval {Cl}, 6.8%, 27.3%]; P = 0.0004). The time to detection was significantly shorter using BacT/Alert bottles (2.0 +/- 2.2 days) than using Schaedler broth (4.6 +/- 3.6 days, P < 0.0001). The culture of osteoarticular specimens in BacT/Alert bottles allows bacterial enrichment with an automated detection of positivity. Their use decreased detection time and increased sensitivity, making it a useful tool for the diagnosis of OAI that should be included among the recommended media. IMPORTANCE Microbiological diagnosis of OAI is based on culture on several media. French experts recommend the use of liquid media such as Schaedler broth, but many laboratories use blood culture media with automated detection in substitution because it is more convenient. We report here a prospective multicentric study evaluating the performance of culture in BacT/Alert (bioMerieux) bottles for microbiological diagnosis of OAI in comparison with culture in Schaedler broth. A total of 1,616 osteoarticular specimens from 349 patients were collected and inoculated onto agar, into BacT/Alert aerobic and anaerobic bottles, and into a Schaedler broth. BacT/Alert bottles were significantly more sensitive than the Schaedler process for OAI diagnosis (+17.0% [95% CI, 6.8%, 27.3%], P = 0.0004). The time to detection was significantly shorter for the BacT/Alert bottles (2.0 +/- 2.2 days) than for Schaedler broth (4.6 +/- 3.6 days, P < 0.0001). This study suggests that the use of BacT/Alert bottles should be recommended in microbiological diagnosis of OAI.

In the context of increasing antimicrobial resistance in Enterobacterales, the management of these UTIs has become challenging. We retrospectively assess the prevalence of antimicrobial resistance in Enterobacterales isolates recovered from urinary tract samples in France, between 1 September 2017, to 31 August 2018. Twenty-six French clinical laboratories provided the susceptibility of 134,162 Enterobacterales isolates to 17 antimicrobials. The most frequent species were E. coli (72.0%), Klebsiella pneumoniae (9.7%), Proteus mirabilis (5.8%), and Enterobacter cloacae complex (2.9%). The overall rate of ESBL-producing Enterobacterales was 6.7%, and ranged from 1.0% in P. mirabilis to 19.5% in K. pneumoniae, and from 3.1% in outpatients to 13.6% in long-term care facilities. Overall, 4.1%, 9.3% and 10.5% of the isolates were resistant to cefoxitin, temocillin and pivmecillinam. Cotrimoxazole was the less active compound with 23.4% resistance. Conversely, 4.4%, 12.9%, and 14.3% of the strains were resistant to fosfomycin, nitrofurantoin, and ciprofloxacin. However, less than 1% of E. coli was resistant to fosfomycin and nitrofurantoin. We identified several trends in antibiotics resistances among Enterobacterales isolates recovered from the urinary tract samples in France. Carbapenem-sparing drugs, such as temocillin, mecillinam, fosfomycin, cefoxitin, and nitrofurantoin, remained highly active, including towards ESBL-E.

Introduction. Even though Corynebacterium aurimucosum has been described in 2002, this species has long been underestimated due to the unreliability of conventional identification methods and only a few cases of infections have been reported.Hypothesis/Gap Statement. Little is known about clinical significance and antimicrobial susceptibility profile of this uncommon species.Aim. To evaluate the clinical relevance of C. aurimucosum and its antimicrobial susceptibility profile.Methodology. All C. aurimucosum isolates, collected from 2010 to 2019 in 10 French university hospitals, were retrospectively included. Demographic, clinical and microbiological data were collected for all cases. Antimicrobial susceptibility testing was performed according to the 2019 EUCAST guidelines.Results. Fifty-seven clinical isolates of C. aurimucosum were collected in 57 patients (median age, 65.8 years; male/female sex ratio, 1.1), mostly from urine (28 %), blood culture (28 %) and bone/synovial fluid (19 %) samples. Of them, 14 cases of infection were confirmed, mainly bone and joint infections (50 %) followed by urinary tract infections (UTIs) (21 %), bacteremia (14 %), skin and soft-tissue infections (14 %). C. aurimucosum was recovered in pure culture in 36 % of cases (UTIs and bacteremia) while mixed cultures were observed for other infections. By testing 52 clinical isolates in vitro, this species appeared to be fully susceptible to linezolid and vancomycin while most isolates (>80 %) were susceptible to amoxicillin (MIC90, 2 µg ml-1), gentamicin, tetracycline and rifampicin. Both cefotaxime and ciprofloxacin seemed to have a limited activity (ca. 50 % of susceptible strains). The MIC distribution for ciprofloxacin showed a bimodal profile with a population of highly-resistant strains with MICs >2 µg ml-1. Most isolates (>90 %) were categorized as resistant to penicillin G and clindamycin.Conclusion. C. aurimucosum should be considered as an actual opportunistic pathogen, and treatment with amoxicillin, vancomycin or linezolid should be preferred.

We describe a case report of hypermucoviscous Klebsiella pneumoniae (KP) promptly diagnosed by blood and cerebrospinal fluid (CSF) culture with positive string test. The patient, without medical history, developed in a few hours multiple localizations, typical of hypervirulent KP . Combination of multiple typical localizations (eye, CSF, pulmonary, hepatic) and string test enabled rapid diagnosis of hypermcoviscous and hypervirulent KP .

Abstract Background Patients infected with the severe acute respiratory syndrome coronavirus 2 (SARS-COV 2) and requiring intensive care unit (ICU) have a high incidence of hospital-acquired infections; however, data regarding hospital acquired bloodstream infections (BSI) are scarce. We aimed to investigate risk factors and outcome of BSI in critically ill coronavirus infectious disease-19 (COVID-19) patients. Patients and methods We performed an ancillary analysis of a multicenter prospective international cohort study (COVID-ICU study) that included 4010 COVID-19 ICU patients. For the present analysis, only those with data regarding primary outcome (death within 90 days from admission) or BSI status were included. Risk factors for BSI were analyzed using Fine and Gray competing risk model. Then, for outcome comparison, 537 BSI-patients were matched with 537 controls using propensity score matching. Results Among 4010 included patients, 780 (19.5%) acquired a total of 1066 BSI (10.3 BSI per 1000 patients days at risk) of whom 92% were acquired in the ICU. Higher SAPS II, male gender, longer time from hospital to ICU admission and antiviral drug before admission were independently associated with an increased risk of BSI, and interestingly, this risk decreased over time. BSI was independently associated with a shorter time to death in the overall population (adjusted hazard ratio (aHR) 1.28, 95% CI 1.05–1.56) and, in the propensity score matched data set, patients with BSI had a higher mortality rate (39% vs 33% p = 0.036). BSI accounted for 3.6% of the death of the overall population. Conclusion COVID-19 ICU patients have a high risk of BSI, especially early after ICU admission, risk that increases with severity but not with corticosteroids use. BSI is associated with an increased mortality rate.

OBJECTIVES:This multicenter study aimed to assess the performances of gradient diffusion (GD) method in comparison to broth microdilution (BMD) method for susceptibility testing of dalbavancin, daptomycin, vancomycin, and teicoplanin. METHODS:Minimum Inhibitory Concentrations (MICs) were retrospectively determined concomitantly by BMD and GD methods, for 93 staphylococci and enterococci isolated from clinical samples. BMD was considered as the gold standard. Essential (EA) and categorical agreements (CA) were calculated. Discordant categorical results were categorized as major (ME) and very major errors (VME). RESULTS:EA and CA were 95.7% and 96.8%, 82.8% and 100%, 97.8% and 96.8%, and 94.6% and 95.7% for dalbavancin, daptomycin, vancomycin, and teicoplanin respectively. Concerning dalbavancin, 3 ME without any VME were observed and discrepancies were low (≤ to 2 two-fold dilutions) between both methods. VME were noted in 1 and 3 cases for vancomycin and teicoplanin, respectively, and resulted from 1 two-fold dilution discrepancy in each case. EA was lower for daptomycin. When they were discrepant, BMD MICs were systematically higher than GD ones. Nevertheless, no categorical discrepancy was noted. CONCLUSIONS:GD appears as an acceptable and convenient alternative for dalbavancin, vancomycin, and teicoplanin MICs determination. Our study also emphasizes how achieving accurate daptomycin MICs remains challenging.

BACKGROUND:Quinolone resistance (QR) is one component of the MDR emerging in Escherichia coli and is of particular concern given the widespread use of fluoroquinolones.OBJECTIVES:To characterize the QR phenotypes and genotypes in E. coli responsible for bloodstream infections and to propose molecular determinants that could be targeted to predict ciprofloxacin resistance.METHODS:E. coli isolates from blood cultures in three French hospitals were studied for quinolone MICs and characterization of genotypic QR determinants (QRg).RESULTS:Among 507 isolates tested for MICs, 148 (29.2%) were resistant to quinolones based on EUCAST breakpoints and 143 (28.2%) harboured at least one QRg. QRg were mainly mutations in the QRDR (138 isolates, 27.2%), with 55.8% of these isolates carrying at least three QRDR mutations. gyrA mutations predominated (92.8%) followed by parC (61.6%), parE (32.6%) and gyrB (1.4%) mutations. Only 4.7% of the isolates harboured a plasmid-mediated quinolone resistance (PMQR) gene: aac(6')-Ib-cr (60.0%) or qnr (qnrS, qnrB) (32.0%). For the first time in France, we reported the qepA4 allele of the plasmid-encoded efflux pump QepA. Only five isolates carried PMQR without a QRDR mutation. The positive predictive value (PPV) for ciprofloxacin resistance was 100% for any QRg and 99.2% for gyrA mutations specifically.CONCLUSIONS:QR observed in E. coli isolates involved in bloodstream infections is still mainly due to QRDR mutations, especially at codons GyrA83/87, which could be used as a molecular target to rapidly detect resistance.

The fosfomycin breakpoint using the disc diffusion method (DDM) changed in the 2019 CA-SFM/EUCAST guidelines v2 (24mm versus 19 mm). We assessed its impact on categorization of Enterobacterales recovered from urine samples in emergency departments. A total of 7749 and 2348 strains were tested using the DDM and the broth microdilution method (BMD), respectively. The DDM with the 19-mm breakpoint was in accordance with the BMD. Using the 24-mm breakpoint, the overall rate of fosfomycin resistance in Enterobacterales increased by three-fold (5.6% vs 18.1%, P < 0.01) and reached 2.8% and 86.5% in E. coli and K. pneumoniae, respectively. French guidelines for the management of community-acquired UTI remain appropriate. The accuracy of the methods for routine fosfomycin susceptibility testing should be assessed. The role of fosfomycin in the treatment of documented CA-UTI due to Enterobacterales other than E. coli should be evaluated considering its rate of resistance and recent data reporting low accuracy. (C) 2020 Elsevier Masson SAS. All rights reserved.

La résistance aux antibiotiques des entérobactéries est un problème majeur de santé publique. La pandémie de souches productrices de BLSE (E-BLSE), notamment parmi l’espèce Escherichia coli, est particulièrement préoccupante de par sa diffusion dans la communauté. En France, 3,6 % des infections urinaires communautaires (IUC) sont dues à une E-BLSE [1]. Ces IUC sont les plus fréquentes infections liées à des entérobactéries dans la communauté. Les recommandations nationales de leur prise en charge ont récemment été actualisées [2]. Nous proposons d’évaluer la prévalence de la résistance aux antibiotiques recommandés pour le traitement des IUC. Étude rétrospective multicentrique entre septembre 2017 et aout 2018 ; – Participants : 19 laboratoires hospitaliers ; – Inclusion de toutes les souches d’entérobactéries isolées d’un prélèvement d’urine réalisé aux urgences, 1 seule souche de même profil incluse par patient ; – Interprétation de la sensibilité aux antibiotiques selon les recommandations EUCAST 2017 ; – Caractérisation de la résistance aux C3G par méthode phénotypique. Au total, 22 420 souches ont été incluses. Les 3 espèces les plus fréquentes étaient E. coli (75,9 %), Klebsiella pneumoniae (9,1 %) et Proteus mirabilis (4,8 %). Les E-BLSE représentaient 6,6 % de l’ensemble des souches. Leur prévalence était significativement plus élevée en Île-de-France (7,4 %) par rapport aux autres régions (5,9 %) (p < 0,01). Les souches d’E. coli produisaient significativement moins de BLSE que les souches de K. pneumoniae (6,4 % vs 18,9 %, p < 0,01). Les antibiotiques les plus actifs étaient la fosfomycine, les furanes, et le mecillinam (taux de résistance de 4,5 %, 10,5 % et 11,3 % respectivement). Les taux de résistance étaient plus élevés pour la ciprofloxacine (15,9 %), l’ofloxacine (16,4 %), le cotrimoxazole (24,1 %) et l’amoxicilline-acide clavulanique (30,9 %). Parmi les 3 espèces les plus fréquentes, il n’y avait pas de différence du taux de résistance pour la majorité des antibiotiques. Néanmoins, P. mirabilis était significativement plus résistant au mecillinam (34,7 %) et K. pneumoniae à la fosfomycine (17,0 %). E. coli était significativement plus sensible aux furanes (1,4 %) et P. mirabilis à l’amoxicilline-acide clavulanique (13,3 %). Par rapport à un précédent travail multicentrique [2], nos résultats semblent montrer une augmentation de la prévalence des E-BLSE, qui est plus élevée en Île-de-France. Bien que plusieurs souches aient pu être isolées dans un contexte d’infections associées aux soins ou de bactériuries asymptomatiques, la majorité des antibiotiques recommandés pour le traitement probabiliste des IUC aux urgences conservent une activité in vitro sur les principales souches impliquées. Le taux de résistance à la ciprofloxacine est néanmoins supérieur à 10 %.