Comparison of the in vitro activities of delafloxacin and comparators against Staphylococcus epidermidis clinical strains involved in osteoarticular infections: a CRIOGO multicentre retrospective study.

OBJECTIVES: Staphylococcus epidermidis bone and joint infections (BJIs) on material are often difficult to treat. The activity of delafloxacin has not yet been studied on S. epidermidis in this context. The aim of this study was to assess its in vitro activity compared with other fluoroquinolones, against a large collection of S. epidermidis clinical strains. METHODS: We selected 538 S. epidermidis strains isolated between January 2015 and February 2023 from six French teaching hospitals. One hundred and fifty-two strains were ofloxacin susceptible and 386 were ofloxacin resistant. Identifications were performed by MS and MICs were determined using gradient concentration strips for ofloxacin, levofloxacin, moxifloxacin and delafloxacin. RESULTS: Ofloxacin-susceptible strains were susceptible to all fluoroquinolones. Resistant strains had higher MICs of all fluoroquinolones. Strains resistant to ofloxacin (89.1%) still showed susceptibility to delafloxacin when using the Staphylococcus aureus 2021 CA-SFM/EUCAST threshold of 0.25 mg/L. In contrast, only 3.9% of the ofloxacin-resistant strains remained susceptible to delafloxacin with the 0.016 mg/L S. aureus breakpoint according to CA-SFM/EUCAST guidelines in 2022. The MIC50 was 0.094 mg/L and the MIC90 was 0.38 mg/L. CONCLUSIONS: We showed low delafloxacin MICs for ofloxacin-susceptible S. epidermidis strains and a double population for ofloxacin-resistant strains. Despite the absence of breakpoints for S. epidermidis, delafloxacin may be an option for the treatment of complex BJI, including strains with MICs of ≤0.094 mg/L, leading to 64% susceptibility. This study underlines the importance for determining specific S. epidermidis delafloxacin breakpoints for the management of BJI on material.

Assessment of the automated multiplex-PCR Unyvero i60 ITI® cartridge system to diagnose prosthetic joint infection: a multicentre study.

OBJECTIVES: Prosthetic joint infections (PJI) are responsible for significant morbidity and mortality and their number continues to rise. Their management remains complex, especially the microbiological diagnosis. Besides 'homemade' tests developed by several teams, new molecular biology methods are now available with different analytical performance and usability. METHODS: We studied the performances of one of these tests: ITI® multiplex PCR (mPCR) by the Curetis® company and compared it to either 'optimized' culture or 16S rRNA PCR. We performed a retrospective multicentre study to assess the contributions of mPCR in the diagnosis of PJI. We randomly selected 484 intraoperative specimens among 1252 of various types (biopsy, bone, tissue around the prosthesis, synovial fluid) from 251 patients in seven different hospitals. Each sample was treated according to the recommendations of the manufacturer. RESULTS: In all, 154 out of 164 (93.9%) samples negative in culture were negative with the mPCR. Among the 276 positive samples in culture, 251 (90.9%) were monomicrobial, of which 119 (47.4%) were positive with the mPCR, and 25 (9.1%) were polymicrobial, of which 12 (48%) were positive with the mPCR. The concordance rate of mPCR with culture was 58.1% (53.6%-62.7%) and the concordance rate with 16S rRNA PCR was 70.1% (65.5%-74.6%). CONCLUSION: This new standardized molecular test showed a lack of detection when the bacterial inoculum was low (number of positive media per sample and number of colonies per media) but can be useful when patients have received antibiotic therapy previously.

Decline in antibiotic resistance and changes in the serotype distribution of Streptococcus pneumoniae isolates from children with acute otitis media; a 2001-2011 survey by the French Pneumococcal Network.

Streptococcus pneumoniae is an important cause of acute otitis media (AOM). The aim of this study was to evaluate trends in antibiotic resistance and circulating serotypes of pneumococci isolated from middle ear fluid of French children with AOM during the period 2001-2011, before and after the introduction of the PCV-7 (2003) and PCV-13 (2010) vaccines. Between 2001 and 2011 the French pneumococcal surveillance network analysed the antibiotic susceptibility of 6683 S. pneumoniae isolated from children with AOM, of which 1569 were serotyped. We observed a significant overall increase in antibiotic susceptibility. Respective resistance (I+R) rates in 2001 and 2011 were 76.9% and 57.3% for penicillin, 43.0% and 29.8% for amoxicillin, and 28.6% and 13.0% for cefotaxime. We also found a marked reduction in vaccine serotypes after PCV-7 implementation, from 63.0% in 2001 to 13.2% in 2011, while the incidence of the additional six serotypes included in PCV-13 increased during the same period, with a particularly high proportion of 19A isolates. The proportion of some non-PCV-13 serotypes also increased between 2001 and 2011, especially 15A and 23A. Before PCV-7 implementation, most (70.8%) penicillin non-susceptible pneumococci belonged to PCV-7 serotypes, whereas in 2011, 56.8% of penicillin non-susceptible pneumococci belonged to serotype 19A. Between 2001 and 2011, antibiotic resistance among pneumococci responsible for AOM in France fell markedly, and PCV-7 serotypes were replaced by non-PCV-7 serotypes, especially 19A. We are continuing to assess the impact of PCV-13, introduced in France in 2010, on pneumococcal serotype circulation and antibiotic resistance.

Outbreak of extended spectrum beta-lactamase-producing Klebsiella pneumoniae in an intensive care unit (Brest).

INTRODUCTION: We had for aim to describe control and investigation of an outbreak caused by a strain of Extended spectrum beta-lactamase producing Klebsiella pneumoniae in intensive care units of the Brest teaching hospital. PATIENTS AND METHOD: The case definition was a patient infected by or carrying the epidemic strain. Control measures and investigations are presented. A case-control study was conducted in the surgical intensive care unit. Each case was matched with two controls based on admission times in the unit. The study focused on diagnostic and therapeutic procedures, and potential contacts with healthcare workers, in this context of cross transmission. RESULTS: Between February and May 2011, nine cases were reported in the surgical ICU and two in the medical ICU. Eighteen controls were matched with the nine surgical ICU cases. Several factors were found to be statistically associated with infection or colonization by the epidemic strain: the surgical block in which patients had been operated and the ward of first hospitalization; the number of trans-esophageal and trans-thoracic echocardiographies, of central venous catheter insertions, and of surgical operations; intubation. The total number of invasive procedures was also found to be statistically higher among cases. CONCLUSION: This study identified factors associated with colonization or infection by the epidemic strain. These factors might have been involved in the transmission tree, and be vulnerable elements for the prevention of nosocomial infections and colonisations, and their epidemic spread.

Investigation and management of an imipenem-resistant oxa-23 Acinetobacter baumannii outbreak in an intensive care unit.

OBJECTIVES: The study objectives were to describe the investigation and management of an imipenem-resistant Acinetobacter baumannii outbreak that occurred in the 15-bed ICU of a tertiary care teaching hospital (Brest, France), during the summer 2008. PATIENTS AND METHODS: Patients harboring an imipenem-resistant A. baumannii strain were defined as case patients. We described case occurrence and steps taken to control the outbreak: contact isolation, reinforcement of hygiene procedures, unit shutdown decision, unit disinfection, and reopening. We also made a case control study and a cost analysis of the outbreak management. RESULTS: During a 10-day period, five patients were positive for a single clone of imipenem-resistant oxa-23 A. baumannii. Four patients presented with ventilation-acquired pneumonia and one was asymptomatic. The first two patients died one day after the first swab which led to the identification of A. baumannii. No additional case was noted in the ICU or in other hospital units after deciding to close the ICU. The cost of outbreak management was estimated at 264,553 euros. The case control study identified several factors associated with infection or colonization: length of stay in the ICU, chronic respiratory disease, number of previous antibiotic classes used, duration of ventilation, prone position, echocardiography, and presence of a nasogastric tube. CONCLUSION: This outbreak occurred during the summer period requiring the shutdown of the ICU and inducing a considerable cost. Rapid reactions of the ICU staff during the outbreak enabled to limit the epidemic.

[Epidemiology of healthcare-associated infections due to MRSA in Brest University Hospital from 2004 to 2007. Impact of hydroalcoholic gel and antibiotics consumptions]. / Épidémiologie des infections nosocomiales à SARM au CHU de Brest du 1(er) janvier 2004 au 31 décembre 2007. Impact des consommations de produits hydroalcooliques et d'antibiotiques.

UNLABELLED: The fight against healthcare-associated infections is based on preventive measures of multidrug resistant bacteria diffusion. Hand hygiene is the simplest and the most effective preventive measure to reduce cross-transmission of infectious agents. Hydroalcoholic solutions for hand hygiene was recently introduced in the University Hospital of Brest (France). The aims of the study were: to describe the epidemiology of healthcare-associated infections due to methicillin-resistant Staphylococcus aureus (MRSA); to determine the annual consumptions of antistaphylococcal antibiotics; and to discuss the relation between consumption of antiseptic products or antibiotics and the epidemiology of MRSA. METHODS: A retrospective epidemiological and pharmaco-epidemiological study was realized from January 2004 to December 2007 in the University Hospital of Brest (France). It allowed to bring to light the cases of healthcare-associated infections due to MRSA and to quantify the consumptions of hang hygiene products and antistaphylococcal antibiotics. RESULTS: this retrospective study showed a decrease of healthcare-associated infections due to MRSA and an increase of the consumption of hydroalcoholic solutions. Antistaphylococcal resistance rates also decreased in a context of fall of the global antibiotics consumption in the hospital.

Intrafamilial transmission of extended-spectrum-beta-lactamase-producing Escherichia coli and Salmonella enterica Babelsberg among the families of internationally adopted children.

OBJECTIVES: International adoption from developing countries has become an increasing phenomenon in recent years. Given the high prevalence of multidrug-resistant (MDR) bacteria in these countries, the adopted children represent a group at risk for both carriage and infection with MDR bacteria. The dynamics of intrafamilial transmission of MDR bacteria after adoption was studied in a prospective study from January 2002 to January 2005. METHODS: Stool samples, taken at the first visit to the outpatient adoption practice and subsequently every month, from the adopted children of an orphanage of Bamako (Mali) and from all the members of their adoptive families were screened for MDR bacteria and bacterial pathogens. Bacteria were characterized by standard biochemical methods, disc diffusion antibiograms, PFGE and plasmid analysis. beta-Lactamase genes were sought by PCR. RESULTS: Over the study period, 52 ESBL-producing Enterobacteriaceae (E-ESBL), with Escherichia coli (56%) being the most prevalent, were isolated from 24/25 adoptees at arrival in France. During follow-up, the transmission of ESBL-producing E. coli and Salmonella enterica Babelsberg between the adoptees and their adoptive family members has clearly been demonstrated for 5/22 families (23%). The mean duration of the carriage for the adopted children was 9 months (1-15 months). CTX-M-15 was the most prevalent resistance gene among the E-ESBLs (93%), while SHV-12 was found among the S. enterica Babelsberg studied. CONCLUSIONS: International travellers, transfer of patients and now adoption may contribute to the global emergence of MDR bacteria. Thus, in addition to the usual screening of adopted children for infectious diseases, additional screening for MDR bacteria should be recommended, at least for children coming from countries with a high prevalence of MDR bacteria.

[Septic arthritis after arthroscopic cruciate ligament reconstruction: in vitro comparison of the behavior of two types of interference screws towards the Staphylococcus aureus adherence]. / Arthrite septique après ligamentoplastie du pivot central sous arthroscopie : comparaison in vitro du comportement de deux types de vis d'interférence vis-à-vis de la fixation du Staphylococcus aureus.

PURPOSE OF THE STUDY: We report the results of an experimental study designed to investigate the behaviour of two types of interference screws (bioabsorbable versus titanium) in a context of Staphylococcus aureus infection. The main objective was to study one of the possible sources of failure for the treatment of acute arthritis of the knee after arthroscopic reconstruction of the cruciate ligament. MATERIAL AND METHODS: We used six interference screws made of titanium and six bioabsorbable screws (PLLA-PDLLA). All screws measured 9mmx25mm, were cannulized and sterilized. These screws were submitted to a protocol elaborated in cooperation with the bacteriologists. After contamination with a strain of S. aureus, the screws were washed four times in saline solution to eliminate germs adsorbed in the aqueous phase. The last step was trypsination to detach germs remaining fixed onto the screws and contained in the biofilms of glycocalix. A germ count was made after each step. For each screw, we determined the difference (Delta) corresponding to the number of germs really adherent to the screw. Mann-Whitney analysis was performed. RESULTS: On average, the germ count in the aqueous phase was 0.0855.10(5)/ml for the titanium screw versus 0.223.10(5)/ml for the bioabsorbable screw. The mean count of germs fixed in the biofilm (mean Delta) was 17.695+/-3.88.10(5) for the titanium screw and 45.86+/-3.61.10(5) for the bioabsorbable screw. The difference was statistically significant (p=0.0039). DISCUSSION: Our experimental results support the efficacy of abundant arthroscopic lavage in a context of infection, confirming the results of very recent studies. However, irrespective of the type of material used, bioabsorbable screws are more prone to persistent microbial adherence than titanium screws. It is hypothesized that the hydrophilic, more porous microstructure of bioabsorbable screws favors bacterial adherence. In practice, this implies that arthroscopic washout must be as abundant and as complete as possible, yet may not be sufficient to clean the entire surface of potentially contaminated screw positioned deep in a bony tunnel.

[Evolution of antibiotic resistance and serogroups of Streptococcus pneumoniae over the 1997-2003 period in Brittany]. / Evolution de la résistance aux antibiotiques et des sérogroupes de Streptococcus pneumoniae en Bretagne entre 1997 et 2003.

At this time, many antibiotics have decreased activity against Streptococcus pneumoniae, a major agent of infectious disease. In this study, we evaluated antibiotic susceptibility and serogroups of strains isolated from bacteraemia, meningitis and acute otitis media in adults and children over the 1997-2003 period in Brittany, France. In 2003, 62% of the isolates were not susceptible to penicillin and 11% were fully resistant. The prevalence of erythromycin resistance was 63%. Resistance rates were higher among isolates recovered from children than adults. Serogroups 19 and 14 were the most frequently isolated, especially the 19 one among children. The emergence of this serogroup might be a consequence of the use of heptavalent conjugate vaccine introduced in 2001 in France. Future surveillance after vaccination will be needed to detect emerging serogroups and resistance among S. pneumoniae.

[Bacteremia and pneumonia due to Yersinia enterocolitica serotype O:3 in an immunocompetent patient]. / Bactériémie et pneumopathie à Yersinia enterocolitica sérotype O:3 chez un immunocompétent.

The authors report a rare case of Yersinia enterocolitica O:3 pneumonia in an immunocompetent 70-year old man. There was no evidence of acute gastrointestinal disease. Diagnosis was confirmed by blood cultures. He responded with resolution of the infection after 21 days of therapy with a third-generation cephalosporin then by cotrimoxazole. Only 15 cases have been reported so far. Most of the patients were immunocompromised. This is the first case in France.