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Objectives Incidence of extended-spectrum β-lactamase-producing Gram-negative bacilli (ESBL-PE-GNB)-related infections is worryingly increasing worldwide. ESBL-PE-GNB detection directly on bronchial aspirate samples (BAS) performed for suspected pneumonia may help save empirical carbapenems. Our objectives were to optimize β-LACTA™ test (BLT) realization and evaluate BLT performance for ESBL-PE-GNB detection directly on BAS. Methods We studied BLT technical optimization using BAS of different matrix types spiked with increasing concentrations of CTX-M-15-producing Klebsiella pneumoniae; in vitro validation of BLT diagnostic performance on 17 ESBL enzymes, belonging to CTX-M, SHV, TEM, OXA, GES, VEB and PER groups; and clinical validation of BLT performance on 126 BAS prospectively collected from seven intensive care units. Results After optimization, BLT detected with 100% sensitivity the presence of CTX-M-15-producing K. pneumoniae spiked in sterile BAS for inoculums upon two or more GNB per field upon microscopic Gram staining examination (MGSE). The BLT accurately detected the 17 ESBLs tested at 10 6 CFU/mL and all ESBLs except Pseudomonas aeruginosa –related OXA-14 at 10 4 CFU/mL. Among the 126 BAS of the validation cohort, 21 (17%) gave positive BLT (ten in BAS positive and 11 in BAS negative on MGSE). All BLT-positive BAS grew with ESBL-PE-GNB, including five hyper-L2-producing Stenotrophomonas maltophilia strains. BLT detected ESBL-PE-GNB directly on clinical BAS positive for GNB on MGSE and/or growing with ≥10 4 CFU/mL with 100% sensitivity, specificity, and positive and negative predictive values. Conclusions BLT is an accurate tool for ESBL-PE-GNB detection directly on BAS. Further studies are needed to evaluate the impact of BLT-guided early antimicrobial de-escalation strategies. [ABSTRACT FROM AUTHOR]

Although extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae have become a worldwide public health concern, little is known regarding the clinical course of colonized or infected individuals. Our objective was to characterize the determinants of fatal outcomes related to ESBL-producing microorganisms at a large hospital in Paris, France. In 2012-2013, all consecutive patients with clinical samples testing positive for ESBL-producing Enterobacteriaceae at Saint-Antoine Hospital were identified. Patient clinical data were obtained at hospital entry, while information on intensive care unit (ICU) admissions and death were prospectively collected. Risk-factors for fatal 1-year outcomes were assessed using logistic regression. In total, 643/4684 (13%) ESBL-positive samples were observed, corresponding to 516 episodes ( n = 206, 40% treated) among 330 patients. Most episodes were nosocomial-related ( n = 347/516, 67%) involving Escherichia coli ( n = 232/516, 45%) or Klebsiella pneumoniae ( n = 164/516, 32%). Empirical antibiotic therapy was adequate in 89/206 (43%) infections, while the median length of hospital stay was 30 days [interquartile range (IQR) = 11-55] and 39/201 (19%) were admitted to the ICU. Overall, 104/241 patients (43%) with available data died within 1 year. In the multivariable analysis, 1-year death was associated with age >80 years ( p = 0.01), concomitant comorbidity ( p = 0.001), nosocomial-acquired infection ( p = 0.002), and being infected rather than colonized ( p < 0.001). In this series of patients with identified samples of ESBL-producing Enterobacteriaceae, hospital burden was large and 1-year mortality rates high. Understanding which patients in this setting would benefit from broad-spectrum empirical antibiotic therapy should be further examined. [ABSTRACT FROM AUTHOR]

The dissemination of antimicrobial resistance genes in Enterobacteriaceae has been largely attributed to plasmids, circular DNA molecules capable of autonomous replication. Whereas high-copy-number plasmids primarily rely on passive diffusion for plasmid maintenance, low-copy-number plasmids utilize so-called partition (par) systems. Plasmid partition relies on three structures, i.e. a centromere like DNA site, a centromere-binding protein and an ATPase or a GTPase motor protein for plasmid positioning. Identification and classification of plasmids is essential for tracing plasmids conferring drug resistance. PCR-based replicon typing is currently the standard method for plasmid identification but there are new classification schemes, especially the relaxase gene typing (PRaseT). Here we developed a multiplex PCR set targeting par loci found on the plasmids most frequently encountered in Enterobacteriaceae. This method, called “plasmid partition gene typing” (PAR-T), was validated with 136 transconjugants or transformants harboring various replicon types. The method was tested with 30 multidrug-resistant clinical isolates including Escherichia coli , Klebsiella pneumoniae and Salmonella enterica subsp. enterica carrying 1-4 replicons; all replicons were tested in parallel with PRaseT for comparison. Six multiplex PCRs and one simplex PCR including 18 pairs of primers recognized plasmids of groups IncA/C, FIA, FIB, FIC, FIIk, FII, HI1, HI2, I1, L/M, N, X. Our set of multiplex PCRs showed high specificity for the classification of resistance plasmids except for IncX replicons. [ABSTRACT FROM AUTHOR]

Objectives A relapse from Escherichia coli bloodstream infection was observed in a patient with acute leukaemia treated with ceftazidime for 7 days for febrile neutropenia. Whereas the original E. coli isolate was resistant to β-lactam/β-lactamase inhibitor combinations (EC1), the relapse E. coli isolate showed a similar phenotype but with resistance extended to ceftazidime (EC2). We investigated the molecular mechanisms of β-lactam resistance and sought if EC2 could have been selected in vivo from EC1. Methods EC1 and EC2 isolates were compared for antibiotic MICs, plasmid content, genotyping, β-lactamase genes and their environment. Both isolates were conjugated with E. coli JW4111ΔampC and MICs determined for transconjugants. In addition, ceftazidime-resistant mutants were selected in vitro from EC1. Results EC1 and EC2 showed identical patterns for genotyping and resistance plasmids. PCR sequencing of blaTEM in EC1 showed the mutations M69L and N276D corresponding to TEM-35, also called inhibitor-resistant TEM (IRT)-4. In EC2, the TEM allele showed an additional mutation, R164S, known to confer resistance to ceftazidime. The combination of these three mutations was previously reported in TEM-158, described as the complex mutant TEM (CMT)-9, associated with resistance to β-lactamase inhibitors and third-generation cephalosporins. In vitro selection of ceftazidime-resistant mutants from EC1 yielded six different CMT alleles, including TEM-158 containing the R164S mutation. Conclusions This first known report of in vivo selection of CMT from IRT, reproduced in vitro, shows how the evolution of β-lactamase enzymes is easily driven by antibiotic pressure, even during a short antibiotic therapy. [ABSTRACT FROM PUBLISHER]

Résumé: L’antibioprophylaxie en chirurgie carcinologique ORL diminue l’incidence des infections du site opératoire (ISO). Toutefois, dans certaines chirurgies à risque, réalisées sur des terrains favorisants, avec persistance d’un ensemencement salivaire postopératoire, la question du choix entre antibioprophylaxie et antibiothérapie curative se pose. Nous avons mené une démarche pluridisciplinaire visant à un consensus local en adéquation avec les bonnes pratiques. Pour cela, une revue systématique de la littérature selon les recommandations PRISMA a été réalisée pour répondre aux questions des indications respectives de l’antibioprophylaxie et de l’antibiothérapie curative, de la durée optimale de l’antibioprophylaxie et de la nature de l’antibioprophylaxie en chirurgie carcinologique ORL. À l’issue de ce travail, il apparaît que les patients bénéficiant d’une procédure carcinologique ORL de classe Altemeier 2 à 3 doivent bénéficier d’une antibioprophylaxie peropératoire restreinte aux 24 premières heures postopératoires. Il n’a pas été démontré de bénéfice à sa prolongation au-delà de ces 24heures. Les associations de molécules à privilégier sont « amoxicilline+acide clavulanique » et « clindamycine+gentamicine ». Toutefois, le niveau de preuve concernant les chirurgies les plus délabrantes à haut risque d’ISO apparaît inférieur à celui concernant les chirurgies carcinologiques cantonnées au pharynx ou au larynx, rendant souhaitable la réalisation de nouvelles études randomisées de forte puissance chez ces patients. Il convient enfin de rappeler que l’antibioprophylaxie doit s’intégrer dans un ensemble de mesures préventives des ISO comportant une prise en charge générale du patient, des mesures d’hygiène peropératoires et une surveillance postopératoire attentive des signes d’ISO. [ABSTRACT FROM AUTHOR]

Clin Microbiol Infect 2010; 16: 189–193 From 2002 to 2006, 35 of 73 multidrug-resistant Pseudomonas aeruginosa isolates from different wards at Charles Nicolle hospital of Tunis were positive for class B carbapenemase (using the imipenem–EDTA test), owing to a blaVIM-2 gene cassette in a class 1 integron. Twenty-three isolates additionally produced the extended-spectrum β-lactamase SHV2a. DNA sequences immediately surrounding blaSHV2a shared extensive identity with a Klebsiella pneumoniae plasmid sequence. Despite belonging to the same chromosomal type, as shown by pulsed-field gel electrophoresis (PFGE), the VIM-2 producing P. aeruginosa isolates prevalent at Charles Nicolle hospital displayed a diversity of VIM-2-carrying integrons. [ABSTRACT FROM AUTHOR]

Clin Microbiol Infect 2010; 16: 157–164 During a period of 6 years and 5 months (January 1999 to May 2005), 103 extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae isolates, each from an individual patient or site, were collected at Mongi Slim University Hospital Centre, Tunis, Tunisia. The objectives of our work were the characterization of the bla genes encoding ESBLs, the investigation of clonal diversity of strains, and identification of the transmission modes of the resistance genes. We carried out detection by PCR and sequencing of the blaSHV, blaCTX-M and blaTEM genes, transferability studies, plasmid replicon typing, and analysis by multilocus sequence typing (MLST) on selected isolates. Forty-seven isolates were found to be producers of CTX-M-type ESBLs, of which 43 were CTX-M-15, two CTX-M-14 and two CTX-M-27. Fifty-eight isolates were producers of SHV-12, and three were producers of SHV-2a. More than one ESBL was detected in seven isolates, as five produced both CTX-M-15 and SHV-12, and two produced both CTX-M-27 and SHV-12. By a PCR-based replicon typing method, the plasmids carrying the blaSHV-2a or blaCTX-M-15 genes were assigned to IncFII or, more rarely, to IncL/M types. Of 12 plasmids carrying the blaSHV-12 gene, only one could be typed: it was positive for the HI2 replicon. The MLST results showed large genetic background diversity in the SHV-12-producing isolates and dissemination of specific clones of the CTX-M-15-producing isolates within the same ward and among wards, and suggested endemicity with horizontal dissemination of the blaCTX-M-15 and the blaSHV-12 genes. [ABSTRACT FROM AUTHOR]

Abstract: Aim of the study: An increasing rate of imipenem-resistant Pseudomonas aeruginosa infections has become an important clinical problem in our hospital. The aim of this study is to determine the mechanisms involved in carbapenem resistance. Materials and methods: Ten strains have been randomly selected among 144 clinical isolates of carbapenem-resistant non-metallo-β-lactamase (MBL)-producing P. aeruginosa. A phenotypic and genotypic study was performed using serotyping, antimicrobial susceptibility, detection of MBL and clonality. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used for the expression of the genes oprD, mexA and mexE and by western blot for the expression of OprM. Sequencing of oprD gene was performed. Results: Five genotypes have been determined by arbitrary primer polymerase chain reaction and seven strains were selected to study the mechanisms involved. The predominant serotype was O12. All isolates exhibited high minimum inhibitory concentration (MICs) to both imipenem and meropenem (MIC ranged from 16 to more than 32μg/ml) and did not harbor genes encoding MBL as confirmed by PCR. RT-PCR showed a decline in oprD expression with increased expression of mexA compared to PAO1 wild type strain. None of the isolates overexpressed mexE. Western blot analysis of outer membrane showed overproduction of OprM in all isolates. Conclusion: Resistance to both imipenem and meropenem of clinical isolates of P. aeruginosa was due to two combined mechanisms: decreased transcription of oprD gene and overproduction of the MexAB–OprM efflux system. [Copyright &y& Elsevier]

Abstract: Aim of the study: To determine the prevalence and the diversity of extended-spectrum beta-lactamases (ESBLs) in 196 Klebsiella pneumoniae clinical isolates collected from three hospitals in Algiers. Materials and methods: Antibiograms were done on Mueller-Hinton agar plates with the disc-diffusion method and MICs were determined by agar-dilution method. Mating experiments were performed in agar medium. Plasmid DNA was extracted by the alcalin-lysis method. Total DNA was extracted with a Qiagen mini kit and screened for bla TEM and bla CTX-M genes by PCR. Linkage of bla CTX-M genes with insertion sequence ISEcp1B and class 1 integrons was investigated by PCR. PCR products were sequenced by the Sanger method. The epidemiological relationships between ESBL-producing K. pneumoniae isolates were analyzed by ERIC-PCR. Results: Thirty-nine (19.9%) isolates were found to produce ESBLs belonging to CTX-M-1 group and TEM penicillinases (CTX-M-3, CTX-M-15 and TEM-1). ERIC-PCR analysis showed that the isolates are genetically unrelated. The bla TEM and bla CTX-M genes as well as aminoglycosides and sulfonamides resistance determinants were found located in self-transferable plasmids of approximately 85kb.The class 1 integrons and the insertion sequence ISEcp1B were present in the isolates and in their transconjugants. ISEcp1B was found genetically linked to the bla CTX-M genes and located 127bp upstream, with the presence of the V and W sequences. Conclusion: The study revealed a high rate of ESBL-producing K. pneumoniae in Algerian hospitals, resulting from horizontal dissemination of mobile bla CTX-M genes. [Copyright &y& Elsevier]

Objective: To test the hypothesis that term gestation offers the best outcome. The relationship between gestational age and the extent of bowel injury in fetuses with gastroschisis is a matter of debate. Early delivery and cesarean delivery have been recommended to limit intestinal damage, but their benefits are unclear.Methods: Data on all patients with gastroschisis seen at our institution from 1991 through 2001 were included. Patients were compared based on gestational age: less than 35 weeks, 35-37 weeks, and term (more than 37 weeks) with regard to age at definitive closure, age at first and full feedings, and hospital stay. Statistical significance (P <.05) was determined by analysis of variance and chi(2) analysis.Results: Of the 57 patients, 19.3%, 43.8%, and 36.9% were born at less than 35 weeks, 35-37 weeks, and more than 37 weeks, respectively. Age at definitive closure was significantly higher at 35-37 weeks (5.9 +/- 4.6 days) than at more than 37 weeks (1.5 +/- 2.3 days) and less than 35 weeks (2.6 +/- 2.5 days) (P <.05). A prosthetic pouch (silo) was used more often at 35-37 weeks than at more than 37 weeks or less than 35 weeks (P =.03, chi(2)). Age at first (P =.04) and full feedings (P <.01) and length of hospitalization (P <.01) were all significantly higher at 35-37 weeks than at more than 37 weeks.Conclusion: Based on a homogeneous cohort of patients in whom gastroschisis was diagnosed antenatally, term delivery results in earlier closure of the defect and shorter time to full feedings. The benefit of early delivery postulated by others cannot be substantiated. [ABSTRACT FROM AUTHOR]

We aimed to detect the extended-spectrum β-lactamases (ESBLs) secreted by clinical strains of Escherichia coli at Fann University Hospital in Dakar and to characterize them molecularly. We identified 32 isolates producing ESBLs. The CTX-M-15 gene was the most frequently detected ESBL gene, detected in 90.63% of the isolates studied. [ABSTRACT FROM AUTHOR]

Introduction Les bactériémies sont des pathologies graves avec une morbi-mortalité importante. Le délai d’introduction de l’antibiothérapie efficace est un facteur pronostic majeur des bactériémies. L’émergence et la diffusion des bactéries multirésistantes rendent de plus en plus difficile la juste prescription des antibiotiques. L’identification rapide de la bactérie et de ses gènes de résistance au cours d’une bactériémie permettrait d’optimiser l’antibiothérapie ce qui améliorerait la prise en charge du malade, limiterait la sélection de bactéries encore plus résistantes et diminuerait le coût pour l’hôpital. Nous avons réalisé une étude observationnelle évaluant les pratiques d’antibiothérapie et les conséquences cliniques de ces pratiques avant et après utilisation du Verigene ® (Nanosphere, USA). Matériels et méthodes Tout patient hospitalisé ayant un premier épisode de bactériémie en 2015 a été inclus et les données ont été recueillies de manière prospective (groupe V). Les patients ayant eu une bactériémie en 2014 (avant l’utilisation du Verigene ® ) ont été inclus et leurs données ont été recueillies de manière retrospective (groupe T). L’objectif principal de ce projet était de documenter l’impact de l’utilisation du test Verigene ® sur le délai d’antibiothérapie efficace. Les objectifs secondaires étaient de documenter son impact sur le délai d’antibiothérapie optimale, la mortalité précoce et à J30, la consommation d’antibiotiques à dispensation contrôlée, la durée d’hospitalisation globale et en unité de soins intensifs. Résultats Cent vingt-sept patients du groupe V ont été comparés à 94 patients du groupe T. Les 2 groupes étaient comparables en termes de sexe, âge, comorbidités et facteurs d’immunodépression. L’âge médian était de 64 ans. Deux tiers des hémocultures étaient positives à bacilles Gram négatif et 20 % à Staphylocoque sp. Le délai entre le prélèvement et l’identification bactérienne était de 28 heures dans le groupe V et 52 heures dans le groupe T ( p < 0,001). Le délai d’antibiothérapie optimal n’apparaissait pas différent dans les 2 groupes. Tous les gènes de résistances ont été détectés par le Verigene (12 bla CTX-M et 12 bla mecA ) sauf 1 bla TEM mais non inclus dans le panel. La mortalité à J30 était de 8 % dans le groupe T et 2 % dans le groupe V ( p = 0,06). Conclusion Le Verigene ® a été efficace pour identifier les espèces bactériennes et les gènes de résistance avec un gain de 24 heures par rapport à la procédure bactériologique classique. L’impact clinique sur l’antibiothérapie n’a pas pu être démontré dans cette étude. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 49 year old homeless man with a history of chronic alcohol misuse, and was admitted to the hospital for cellulitis of the right leg. The patient had several traumatic erosions on his legs. Furthermore, the patient was treated with amoxicillin and clavulanic acid.

This report describes the first occurrence of the DHA-1 ampCβ-lactamase gene in Proteus mirabilis. The organism was isolated from the vaginal flora of a pregnant woman in a French hospital. The DHA-1β-lactamase gene was identified on the basis of phenotypic characteristics, PCR amplification and sequencing. Antagonism between cefoxitin and the other cephalosporins suggested inducible production of the DHA-1 enzyme. [ABSTRACT FROM AUTHOR]

Introduction – objectifs Le test chromogénique βLACTA™ (Bio-Rad) détecte en 15 minutes les bactéries résistantes aux C3G à partir de colonies sur milieu gélosé. Une étude prospective a évalué dans 2 hôpitaux la performance du test directement sur des urines positives à BGN au direct. Matériels et méthodes Le test βLACTA™ a été effectué sur les culots urinaires centrifugés. Les résultats sont interprétés à 2 puis 15 min, positif (rouge), négatif (jaune), invalide (orange). Les urines hématuriques sont exclues. Sur 4 mois, 530 ECBU de patients issus de différents services ont été testés. Les antibiogrammes, par la méthode de diffusion de disques, ont été réalisés et interprétés selon les recommandations du CA-SFM 2013. Résultats Le taux d’entérobactéries BLSE (E-BLSE) était de 9,2 % (49/530) dont 57,1 % de Escherichia coli (28/49), 32,7 % de Klebsiella pneumoniae (16/49) et 10,2 % d’entérobactéries produisant naturellement une bétalactamase inductible AmpC (5/49). La sensibilité et la spécificité du test étaient respectivement de 83,7 % et de 99,8 %. Neuf tests sur 530 étaient ininterprétables dont 8 contenaient une E-BLSE, pouvant correspondre (i) à une faible quantité de BGN à l’examen direct, (ii) à la présence de plusieurs espèces de BGN avec un faible taux d’E-BLSE (iii) au type de BLSE (faible hydrolyse des C3G). La caractérisation des souches BLSE est en cours. Conclusion La détection rapide des E-BLSE permettrait (1) une antibiothérapie empirique appropriée, (2) une mise en isolement rapide du patient (3) de restreindre l’utilisation empirique de carbapénèmes aux cas positifs. Les résultats préliminaires montrent que 5 patients sur 8 (62,5 %) ont bénéficié d’un changement de traitement suite au résultat du test. [ABSTRACT FROM AUTHOR]

The article describes the case of a 20-year-old man from Gabon with homozygous SS sickle cell disease and leg pain in the mechanical aortic valve, which was permanent for two months.

Presents an abstract of the article `Rollover Injuries in Residential Driveways: Age-related Patterns of Injury,' by Mark L. Silen, et al., published on the online information service of the `Pediatrics' journal.

Class C β-lactamases or cephalosporinases can be classified into two functional groups (1, 1e) with considerable molecular variability (≤20% sequence identity). These enzymes are mostly encoded by chromosomal and inducible genes and are widespread among bacteria, including Proteobacteria in particular. Molecular identification is based principally on three catalytic motifs ( 64 SXSK, 150 YXN, 315 KTG), but more than 70 conserved amino-acid residues (≥90%) have been identified, many close to these catalytic motifs. Nevertheless, the identification of a tiny, phylogenetically distant cluster (including enzymes from the genera Legionella , Bradyrhizobium , and Parachlamydia ) has raised questions about the possible existence of a C2 subclass of β-lactamases, previously identified as serine hydrolases. In a context of the clinical emergence of extended-spectrum AmpC β-lactamases (ESACs), the genetic modifications observed in vivo and in vitro (point mutations, insertions, or deletions) during the evolution of these enzymes have mostly involved the Ω- and H-10/R2-loops, which vary considerably between genera, and, in some cases, the conserved triplet 150 YXN. Furthermore, the conserved deletion of several amino-acid residues in opportunistic pathogenic species of Acinetobacter, such as A. baumannii, A. calcoaceticus, A. pittii and A. nosocomialis (deletion of residues 304-306), and in Hafnia alvei and H. paralvei (deletion of residues 289-290), provides support for the notion of natural ESACs. The emergence of higher levels of resistance to β-lactams, including carbapenems, and to inhibitors such as avibactam is a reality, as the enzymes responsible are subject to complex regulation encompassing several other genes ( amp R, amp D, amp G, etc.). Combinations of resistance mechanisms may therefore be at work, including overproduction or change in permeability, with the loss of porins and/or activation of efflux systems.

Extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) have been classified in the group of resistant bacteria of highest priority. We determined the prevalence of ESBL-E collected in feces from household and shelter pets in Guadeloupe (French West Indies). A single rectal swab was taken from 125 dogs and 60 cats between June and September 2019. The prevalence of fecal carriage of ESBL-E was 7.6% (14/185, 95% CI: 4.2-12.4), within the range observed worldwide. The only risk factor associated with a higher prevalence of ESBL-E rectal carriage was a stay in a shelter, suggesting that refuges could be hotspots for their acquisition. All but one ( Klebsiella pneumoniae from a cat) were Escherichia coli . We noted the presence of a bla CTX-M -1 /IncI1-Iγ/sequence type (ST3) plasmid in 11 ESBL-producing E. coli isolates belonging to ST328 ( n = 6), ST155 ( n = 4) and ST953 ( n = 1). A bla CTX-M -15 gene was identified in the three remaining ESBL-E isolates. The bla CTX-M -1 and most of the antimicrobial resistance genes were present in a well-conserved large conjugative IncI1-Iγ/ST3 plasmid characterized by two accessory regions containing antibiotic resistance genes. The plasmid has been detected worldwide in E. coli isolates from humans and several animal species, such as food-producing animals, wild birds and pets, and from the environment. This study shows the potential role of pets as a reservoir of antimicrobial-resistant bacteria or genes for humans and underlines the importance of basic hygiene measures by owners of companion animals., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Gruel, Couvin, Guyomard-Rabenirina, Arlet, Bambou, Pot, Roy, Talarmin, Tressieres, Ferdinand and Breurec.)

Objective: The aim of this study was to determine which initial surgical treatment results in the lowest rate of death or neurodevelopmental impairment (NDI) in premature infants with necrotizing enterocolitis (NEC) or isolated intestinal perforation (IP)., Summary Background Data: The impact of initial laparotomy versus peritoneal drainage for NEC or IP on the rate of death or NDI in extremely low birth weight infants is unknown., Methods: We conducted the largest feasible randomized trial in 20 US centers, comparing initial laparotomy versus peritoneal drainage. The primary outcome was a composite of death or NDI at 18 to 22 months corrected age, analyzed using prespecified frequentist and Bayesian approaches., Results: Of 992 eligible infants, 310 were randomized and 96% had primary outcome assessed. Death or NDI occurred in 69% of infants in the laparotomy group versus 70% with drainage [adjusted relative risk (aRR) 1.0; 95% confidence interval (CI): 0.87-1.14]. A preplanned analysis identified an interaction between preoperative diagnosis and treatment group (P = 0.03). With a preoperative diagnosis of NEC, death or NDI occurred in 69% after laparotomy versus 85% with drainage (aRR 0.81; 95% CI: 0.64-1.04). The Bayesian posterior probability that laparotomy was beneficial (risk difference <0) for a preoperative diagnosis of NEC was 97%. For preoperative diagnosis of IP, death or NDI occurred in 69% after laparotomy versus 63% with drainage (aRR, 1.11; 95% CI: 0.95-1.31); Bayesian probability of benefit with laparotomy = 18%., Conclusions: There was no overall difference in death or NDI rates at 18 to 22 months corrected age between initial laparotomy versus drainage. However, the preoperative diagnosis of NEC or IP modified the impact of initial treatment., Competing Interests: The authors report no conflict of interests., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

The increasing incidence of carbapenemase-producing Gram-negative bacilli (C-PGNB) represents a major public health challenge. Rapid detection of digestive colonization with C-PGNB is fundamental to control their spread. We performed the validation of a rapid protocol for C-PGNB detection directly on rectal swabs. We developed a protocol combining enrichment by a rapid selective subculture of the rectal swab medium and realization of a Resist-4 O.K.N.V. K-SeT test on the bacterial pellet obtained. The limit of detection and performances of this protocol were validated in vitro on 52 C-PGNB strains spiked on a calibrated sample suspension and confirmed in clinical settings on 144 rectal swabs sampled from patients with C-PGNB digestive colonization ( n  = 48) and controls (patients with extended-spectrum beta-lactamase [ESBL] colonization [ n  = 48] and without carbapenemase/ESBL [ n  = 48]). The protocol detected, with 100% sensitivity, the presence of the 15 OXA-48-, 14 KPC-, 13 NDM-, and 10 VIM-producing GNB from 10 3 CFU/ml. The limit of detection was 2 × 10 2 CFU/ml. Among the 48 C-PGNB-containing rectal swabs of the validation cohort, 46 were accurately detected. False negative were observed for 1 NDM-producing Acinetobacter baumannii strain and 1 OXA-48-producing Escherichia coli strain. The 96 control swabs were negative. Sensitivity and specificity for C-PGNB detection were 97.7% (95% confidence interval [CI], 87.7 to 100) and 100% (95% CI, 96.2 to 100). The negative likelihood ratio was 0.04 (95% CI, 0.01 to 0.16). Considering a C-PGNB digestive colonization prevalence between 0.01% and 0.1%, positive and negative predictive values were 100%. Our protocol is a rapid and low-cost method detecting accurately the digestive colonization with carbapenemase-producing Enterobacteriaceae in 4 h without any requirement for specific equipment., (Copyright © 2021 American Society for Microbiology.)

We undertook a comprehensive comparative analysis of a collection of 30 small (<25 kb) non-conjugative Escherichia coli plasmids previously classified by the gene sharing approach into 10 families, as well as plasmids found in the National Center for Biotechnology Information (NCBI) nucleotide database sharing similar genomic sequences. In total, 302 mobilizable (belonging to 2 MOB rep and 5 MOB RNA families) and 106 non-transferable/relaxase-negative (belonging to three ReL RNA families) plasmids were explored. The most striking feature was the specialization of the plasmid family types that was not related to their transmission mode and replication system. We observed a range of host strain specificity, from narrow E. coli host specificity to broad host range specificity, including a wide spectrum of Enterobacteriaceae . We found a wide variety of toxin/antitoxin systems and colicin operons in the plasmids, whose numbers and types varied according to the plasmid family type. The plasmids carried genes conferring resistance spanning almost all of the antibiotic classes, from those to which resistance developed early, such as sulphonamides, to those for which resistance has only developed recently, such as colistin. However, the prevalence of the resistance genes varied greatly according to the family type, ranging from 0 to 100 %. The evolutionary history of the plasmids based on the family type core genes showed variability within family nucleotide divergences in the range of E. coli chromosomal housekeeping genes, indicating long-term co-evolution between plasmids and host strains. In rare cases, a low evolutionary divergence suggested the massive spread of an epidemic plasmid. Overall, the importance of these small non-conjugative plasmids in bacterial adaptation varied greatly according to the type of family they belonged to, with each plasmid family having specific hosts and genetic traits.

Objective: To expand existing statistical methods to identify clusters of necrotizing enterocolitis (NEC) and spontaneous intestinal perforation (SIP) cases in the neonatal intensive care unit., Methods: In an academic, tertiary referral center, possible NEC or SIP clusters were identified using a binomial distribution scan test. The incidence-density rate (IDR) was calculated as the number of cases per 1,000 patient-days during each possible cluster and compared with the baseline IDR. A structured chart review compared cluster and noncluster cases. Spatial clustering analyzed the physical distribution of cases using the Grimson Test. Repeat analysis included only SIP cases., Result: The initial scan identified 3 suspected temporal clusters. IDR comparison confirmed only 1 cluster. Analysis of SIP only cases revealed similar results. Physical proximity was not a significant factor. Chart review of the SIP and NEC cases revealed significant increases during the confirmed cluster of small for gestational age infant births and indomethacin treatment. Chart review of the SIP only cases in the confirmed cluster revealed no significant differences., Conclusion: Statistical methods distinguish whether suspected case clusters represent a significant increase in baseline incidence. True clusters warrant detailed investigation including spatial analysis and chart review. This approach may have application in other disease processes and populations.

Objectives: Biofilm production in extended spectrum β-lactamase (ESBL)-producing Enterobacteriaceae provides a favourable environment for the exchange of antibiotic-resistance genes and could facilitate widespread dissemination. We aimed to assess biofilm development in ESBL-producing E. coli and K. pneumoniae isolates and determine how development relates to microbiological characteristics and clinical outcomes., Methods: 147 ESBL-producing E. coli and 82 K. pneumoniae were genetically characterized. Biofilm formation was measured at 1.5, 4, 6, and 24 h during culture in blood heart infusion using a microbead immobilization assay (BioFilm Ring test ® ). Results were given as biofilm formation index (BFI) with lower values indicating increased presence of biofilm (range = 0-21)., Results: In total, 57.1% of strains were strong producers of biofilm (BFI < 2), whereas 13.4% lacked biofilm production (BFI > 18). Standard biofilm production (BFI < 7) was common in E. coli isolates (61.9%). For E. coli, biofilm production was less frequently observed in ST131 clones (p = 0.03) but more frequently in strains harbouring toxin (p = 0.008) or adhesin (p = 0.008) virulence factor genes. Despite almost all K. pneumoniae having standard biofilm production (90.2%), there was a 2.4-times higher odds of observing biofilm in ST29/147/323 versus other ST-types (p = 0.13). Patients with standard biofilm producing isolates were not at increased risk of transfer to intensive-care (odds-ratio=2.80, 95%CI=0.59-13.21) or death within 12-months (odds-ratio=1.61, 95%CI=0.75-3.43)., Conclusion: In these ESBL-producing strains, biofilm production is linked to certain virulence factors in E. coli and is common in K. pneumoniae. Further exploration of whether biofilm production increases dissemination and risk of severe clinical outcomes is needed in larger collections of isolates., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

Objective: To genetically characterize clusters of virulence factors (VFs) among extended spectrum β-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae and assess whether these clusters are associated with genetic determinants or clinical outcomes., Methods: One hundred forty-eight E. coli and 82 K . pneumoniae clinical isolates were obtained from 213 patients in Paris, France. Isolates underwent ESBL characterization, MultiLocus Sequence Typing (MLST) typing and phylogenetic group identification. Detection of ten E. coli and seven K . pneumoniae VF-encoding genes were assessed, from which a k -medians partition algorithm with Jaccard similarity measure was used to construct clusters., Results: CTX-M was the predominant ESBL and susceptibility to trimethoprim-sulfamethoxazole (32%), ciprofloxacin (22%) and aminoglycosides (32%) was low. In E. coli , there were five identified clusters, with significantly different distributions of ESBL-sequence type ( P <0.001), ST131 ( P <0.001) and phylogenetic group ( P =0.001) between clusters. "Siderophore exclusive", "siderophore exclusive with iroN " and "adhesin sfa/papGIII-rich" clusters had higher 12-month mortality rates compared to others (49% vs 22%, respectively, P =0.02). In K. pneumoniae , three different clusters, with significantly different distributions of aminoglycoside-sensitivity ( P <0.004), MLST-type ( P <0.001) and relaxase plasmids ( P =0.001) were described., Conclusion: Distinct clusters of E. coli and K. pneumoniae VFs are observed within ESBL-producing isolates and are strongly associated with several genetic determinants. Their association with overall morbidity and mortality requires further evidence., Competing Interests: Disclosure LS received a grant from the “Fondation pour la Recherche Médicale” (DEA20140630021). AB received post-doctoral funding from SIDACTION. PB received a Martinson-Luepker Student Travel Award from the University of Minnesota for the work presented in this manuscript. The authors report no other conflicts of interest in this work.

Travelers are at high risk of acquiring multi-drug resistant Enterobacteriaceae (MRE) while traveling abroad. Acquisition of extended spectrum beta-lactamase producing Enterobacteriaceae (ESBL-E) while traveling has been extensively described, but not that of plasmid-mediated cephalosporinase producing Enterobacteriaceae (pAmpC-E). Here, we characterized the pAmpC-E acquired in 574 French travelers to tropical areas enrolled in the VOYAG-R study. Among the 526 MRE isolated at return, 57 (10.8%) from 49 travelers were pAmpC-E. The acquisition rate of pAmpC-E was 8.5% (49/574) ranging from 12.8% (25/195) in Asia, 7.6% (14/184) in Latin America to 5.1% (10/195) in Africa. The highest acquisition rates were observed in Peru (21.9%), India (21.4%) and Vietnam (20%). The carriage of pAmpC-E decreased quickly after return with 92.5% of colonized travelers being negative at one month. Most enzymes were CMY types (96.5%, n = 55, only met in Escherichia coli), including 40 CMY-2 (70.2%), 12 CMY-42 (21.1%), 1 CMY-6 and two new CMY-2 variants. The remaining were two DHA observed in Klebsiella pneumoniae. CMY-2 producing strains were acquired worldwide whereas CMY-42, except for one, were all acquired in Asia. BlaCMY-2 genes were associated with different plasmid types, including IncI1 (45. 2%), IncF (10%), IncF-IncI (7.5%), IncA/C (5%) and IncR (2.5%) whereas blaCMY-42 were all associated with IncI1 plasmids. Even though the pAmpC-E acquisition rate was much lower than that of ESBL-E, it was significant, especially in Asia, showing that pAmpC-E, especially CMY-type producing E. coli have spread in the community settings of tropical regions., Competing Interests: The authors have declared that no competing interests exist.

Objectives: To describe clinical and molecular characteristics of an outbreak due to metallo-β-lactamases (MBLs) producing Klebsiella pneumoniae collected at Charles Nicolle Hospital of Tunis and to analyze the impact of outer membrane porin (OMP) loss on carbapenem resistance levels., Methods: Between 2010 and 2015, 178 carbapenem-resistant Enterobacteriaceae were isolated. Screening for MBL production was performed using combined disk diffusion method, with imipenem and ethylene diamine tetraacetic acid (EDTA) as inhibitors. Resistance genes and virulence factors were identified by polymerase chain reaction (PCR) and sequencing. Genotyping was performed by pulsed-field gel electrophoresis and multilocus sequence typing. Genetic environment of carbapenemase genes was determined by PCR mapping. Conjugation assays were performed, and plasmids were assigned to incompatibility groups by PCR-based replicon typing. OMPs were profiled by sodium dodecyl sulfate-polyacrilamide gel electrophoresis, and porin genes were sequenced., Results: Nineteen K. pneumoniae (10.6%) showing MBL activity were isolated from patients hospitalized on four different wards. NDM-1 was the only MBL identified, in association with bla OXA-48 . All strains lacked at least one OMP, and carbapenem resistance levels were remarkably elevated in strains lacking OmpK35 and OmpK36. bla NDM-1 was located in IncFIA-type conjugative plasmid, with the same genetic context in all strains. The epidemiological diffusion of bla NDM-1 was due to two clones, one major clone belonging to sequence type (ST) 147 (n = 16) and the other clone belonging to ST307 (n = 3)., Conclusions: This study describes an outbreak of NDM-1-producing K. pneumoniae strains, isolated from a Tunisian hospital, caused by two clones belonging to ST147 and ST307; and highlights the role of OMPs loss, in combination with β-lactamase expression, in conferring high carbapenem resistance.

To understand the evolutionary dynamics of extended-spectrum β-lactamase (ESBL)-encoding genes in Escherichia coli, we undertook a comparative genomic analysis of 116 whole plasmid sequences of human or animal origin isolated over a period spanning before and after the use of third-generation cephalosporins (3GCs) using a gene-sharing network approach. The plasmids included 82 conjugative, 22 mobilizable and 9 non-transferable plasmids and 3 P-like bacteriophages. ESBL-encoding genes were found on 64 conjugative, 6 mobilizable, 2 non-transferable plasmids and 2 P1-like bacteriophages, indicating that these last three types of mobile elements also play a role, albeit modest, in the diffusion of the ESBLs. The network analysis showed that the plasmids clustered according to their genome backbone type, but not by origin or period of isolation or by antibiotic-resistance type, including type of ESBL-encoding gene. There was no association between the type of plasmid and the phylogenetic history of the parental strains. Finer scale analysis of the more abundant clusters IncF and IncI1 showed that ESBL-encoding plasmids and plasmids isolated before the use of 3GCs had the same diversity and phylogenetic history, and that acquisition of ESBL-encoding genes had occurred during multiple independent events. Moreover, the blaCTX-M-15 gene, unlike other CTX-M genes, was inserted at a hot spot in a blaTEM-1-Tn2 transposon. These findings showed that ESBL-encoding genes have arrived on wide range of pre-existing plasmids and that the successful spread of blaCTX-M-15 seems to be favoured by the presence of well-adapted IncF plasmids that carry a Tn2-blaTEM-1 transposon.

Purpose: Since their emergence at the beginning of the century, OXA-48 carbapenemases have spread in the community and in hospitals. To assess the diversity of OXA-48-producing bacterial strains and plasmids in the hospital setting, we studied the strains isolated from patients in three hospitals in the Paris area., Materials and Methods: All possible OXA-48-like strains were included in the study. OXA-48-like and extended-spectrum beta-lactamase-encoding genes were identified, and fingerprinting analysis was performed for all Escherichia coli and Klebsiella pneumoniae strains. The backbones and close genetic environments of bla OXA-48 were assessed by amplifying genes that were specific to the pOXA-48a plasmid and PCR, encompassing the junctions between bla OXA-48 and its direct genetic environment., Results: Overall, 68 strains from 30 patients were studied. These strains belonged to seven different enterobacterial species. OXA-48, OXA-204, and OXA-401 were identified in 62, 3, and 3 isolates, respectively. Additional broad-spectrum beta-lactamases were identified in 34% (23/68) of the strains. The strain diversity was high between and within patients. Identical patterns were observed only within individual patients or among epidemiologically related patients. Plasmid mapping was performed in the 62 OXA-48-producing strains and the 3 OXA-405-producing strains, resulting in the identification of 5 different patterns., Conclusion: Because of their ability to transfer between strains, OXA-48 carbapenemases have a high risk of dissemination and may become endemic in France.

FosA, a glutathione S-transferase that inactivates fosfomycin, has been reported as the cause of enzymatic resistance to fosfomycin. We show that multiple lineages of FosA-producing extended spectrum β-lactamase Escherichia coli have circulated in France since 2012, potentially reducing the efficacy of fosfomycin in treating infections with antimicrobial drug-resistant gram-negative bacilli.

Background: Rapid diagnostic tests detecting microbial resistance are needed for limiting the duration of inappropriateness of empirical antimicrobial therapy (EAT) in intensive care unit patients, besides reducing the use of broad-spectrum antibiotics. We hypothesized that the betaLACTA® test (BLT) could lead to early increase in the adequacy of antimicrobial therapy., Methods: This was a case-control study. Sixty-one patients with BLT-guided adaptation of EAT were prospectively included, and then matched with 61 "controls" having similar infection characteristics (community or hospital-acquired, and source of infection), in whom EAT was conventionally adapted to antibiogram results. Endpoints were to compare the proportion of appropriate (primary endpoint) and optimal (secondary endpoint) antimicrobial therapies with each of the two strategies, once microbiological sample culture results were available., Results: Characteristics of patients, infections and EAT at inclusion were similar between groups. Nine early escalations of EAT occurred in the BLT-guided adaptation group, reaching 98% appropriateness vs. 77% in the conventional adaptation group (p < 0.01). The BLT reduced the time until escalation of an inappropriate EAT from 50.5 (48-73) to 27 (24-28) hours (p < 0.01). Seventeen early de-escalations occurred in the BLT-guided adaptation group, compared to one in the conventional adaptation group, reducing patients' exposure to broad-spectrum beta-lactam such as carbapenems. In multivariate analysis, use of the BLT was strongly associated with early appropriate (OR = 18 (3.4-333.8), p = 0.006) and optimal (OR = 35.5 (9.6-231.9), p < 0.001) antimicrobial therapies. Safety parameters were similar between groups., Conclusions: Our study suggests that a BLT-guided adaptation strategy may allow early beta-lactam adaptation from the first 24 hours following the beginning of sepsis management.

Objectives: To explore the VagCD toxin-antitoxin (TA) systems encoded on plasmids in multiresistant Klebsiella pneumoniae strains., Methods: Previously sequenced K. pneumoniae plasmids were used for in silico analysis and a collection of 63 resistant K. pneumoniae strains was used for epidemiological study. Functional analysis was done after separate cloning of the toxin gene under the control of the arabinose-inducible promoter of pBAD43 and of the antitoxin gene under the control of the constitutive promoter of pUC19., Results: In silico , two types of VagCD systems, VagCD1 and VagCD2, encoded on K. pneumoniae plasmids could be distinguished, 15% carrying one of these TA systems. Moreover, in a collection of antibiotic-resistant K. pneumoniae strains including ESBL or carbapenemase producers, 17.5% of isolates were found to harbour a VagCD TA system. VagCD1 and VagCD2 were proved functional TA systems, with VagD the toxin and VagC its antitoxin, not only in K. pneumoniae but also in Escherichia coli and other Enterobacteriaceae. Toxin expression was found to induce a significant decrease in a bacterial population resulting from both bactericidal and bacteriostatic effects., Conclusions: The vagCD genes of K. pneumoniae encode a functional broad-spectrum TA system and are conserved on the large multiple antibiotic resistance-conferring plasmids in this species., (© The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

We report two cases of bacteremia due to Clostridium difficile from two French hospitals. The first patient with previously diagnosed rectal carcinoma underwent courses of chemotherapy, and antimicrobial treatment, and survived the C. difficile bacteremia. The second patient with colon perforation and newly diagnosed lung cancer underwent antimicrobial treatment in an ICU but died shortly after the episode of C. difficile bacteremia. A review of the literature allowed the identification of 137 cases of bacteremia between July 1962 and November 2016. Advanced age, gastro-intestinal disruption, severe underlying diseases and antimicrobial exposure were the major risk factors for C. difficile bacteremia. Antimicrobial therapy was primarily based on metronidazole and/or vancomycin. The crude mortality rate was 35% (21/60).

Introduction: Guidelines for the management of Parkinson's disease (PD) patients in the perioperative setting are lacking. Areas covered: Here we review potential problems that may arise when PD patients are undergoing an operation. We also review the literature, where available, and provide our expert opinion and recommendations based on experience. Expert commentary: Elderly patients with PD are especially prone to complications in the perioperative setting. Extreme caution must be used to ensure appropriate medication administration, transition to non-oral agents, if indicated, and early mobilization to achieve rapid recovery after surgery.

Background: Dissemination of multidrug-resistant Escherichia coli is closely associated with the worldwide spread of a single clone ST131, which is the main cause of urinary tract and bloodstream infections in patients from nursing homes and immunocompromised patients. The aim of our study was to determine the prevalence of ST131 clone and the replicons involved in the spread of bla CTX-M genes among O25b-ST131 CTX-M-producing E. coli isolates in Lithuania., Methods: The strains included in this study were screened for CTX-M β-lactamase-encoding genes, phylogenetic groups and ST131 clone by PCR. Bacterial conjugation was performed to identify plasmid replicon types responsible for bla CTX-M genes dissemination., Results: A total of 158 E. coli clinical non-duplicate ESBL isolates were analyzed. Nearly half (n = 67, 42.4%) of the investigated E. coli isolates belonged to phylogenetic group B2. The isolates producing CTX-M-92 β-lactamases were identified to be the ST131 clone more frequently than the non-ST131 clone (11.5% vs. 3.1%, p = .035). The CTX-M-15 isolates were identified as ST131 isolates less frequently than non-ST131 isolates (50.8% vs. 71.1%; p = .015). The ST131 clone isolates contained type L/M and A/C replicons; a fused FII/FIB replicon was found in four isolates (23.5%). Type HI1 replicon was identified in ST131 E. coli isolates producing CTX-M-15 β-lactamases., Conclusions: This study demonstrates the predominance of the ST131 clone among CTX-M β-lactamase-producing E. coli isolates. Dissemination of bla CTX-M genes in ST131 strains can be linked not only to highly adapted IncF plasmids such as FII/FIB and FII, but also to plasmid replicon types A/C, L/M and HI1.