Carbapenemase-producing Enterobacteriaceae in Europe: a survey among national experts from 39 countries, February 2013

Detection of OXA-48-type carbapenemase-producing Enterobacteriaceae in diagnostic laboratories can be enhanced by addition of bicarbonates to cultivation media or reaction buffers

Carbapenemase-mediated resistance to carbapenems in Enterobacteriaceae has become the main challenge in the treatment and prevention of infections recently. The partially unnoticed spread of OXA-48-type carbapenemase producers is usually assigned to low minimum inhibitory concentrations (MICs) of carbapenems that OXA-48-producing isolates often display. Therefore, there is an urgent need of specific and sensitive methods for isolation and detection of OXA-48 producers in clinical microbiology diagnostics. The influence of bicarbonates on carbapenem MICs against carbapenemase-producing Enterobacteriaceae was tested. We also checked whether the addition of bicarbonates to liquid media supplemented with meropenem may facilitate the selective enrichment of various carbapenemase producers in cultures. Furthermore, the sensitivity of carbapenemase confirmation by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) and spectrophotometric hydrolysis assays upon the addition of NH4HCO3 was examined. The addition of NaHCO3 significantly increased MICs of ertapenem and meropenem for OXA-48 producers. Furthermore, liquid media supplemented with NaHCO3 and meropenem were reliable for the selective enrichment of carbapenemase producers. The presence of NH4HCO3 in buffers used in the spectrophotometric and MALDI-TOF MS carbapenemase detection increased the sensitivity of that assay. Our results demonstrate that bicarbonates in media or reaction buffers can enhance the sensitivity of screening methods and diagnostic tests for carbapenemase producers.

Cross-border comparison of the Dutch and German guidelines on multidrug-resistant Gram-negative microorganisms

BACKGROUND

In all European countries, hospital-acquired infections caused by Gram-negative multidrug-resistant microorganisms (GN-MDRO) are a major health threat, as these pathogens cannot be adequately treated anymore, or the start of effective antibiotic treatment is delayed. The efforts to limit the selection and spread of GN-MDRO remains a problem in cross-border healthcare, as the national guidelines on hygiene standards applicable for patients colonized or infected with GN-MDRO in hospitals are not harmonized between European countries.

METHODS

In order to point out the similarities and differences in the national guidelines of Germany and The Netherlands regarding GN-MDRO, guidelines were compared and an expert workshop was organized by the INTERREG IVa project EurSafety Health-net.

RESULTS

Both guidelines divide the Gram-negative organisms into subgroups based on bacterial species and antibiotic susceptibility patterns in order to define multidrug-resistant variants of these bacteria. However, the Dutch guideline defines that GN-MDRO Enterobacteriaceae requires testing for certain mechanisms causing antibiotic resistance, whereas the German guideline makes use of a newly created classification scheme, based on phenotypic characterization. Besides diagnostic issues, the main difference between the Dutch and German guideline is the divergent evaluation of ESBL-producing Enterobacteriaceae. Special hygiene measures are required for all patients with ESBL-producing Enterobacteriaceae in The Netherlands, whereas the German guideline recommends special precautions only for those cases in which patients are colonized or infected with strains showing co-resistance to ciprofloxacin ("3MRGN").

CONCLUSIONS

The usage of consistent terminology and harmonized diagnostic procedures would improve the possibilities for infection prevention, treatment and patient safety. Prevention of severe non-treatable infections and outbreaks due to MDRO, caused by an increased population seeking medical treatment abroad together with an increased number of highly susceptible individuals demands gathering of regional data, and data comparable between the two sides of the Dutch-German border. The necessity to cooperate multidisciplinary and across borders is required to prevent a post-antibiotic era - in which common infections and minor injuries may lead to death.

β-lactam and β-lactamase inhibitor combinations in the treatment of extended-spectrum β-lactamase producing Enterobacteriaceae: time for a reappraisal in the era of few antibiotic options?

The spread of extended-spectrum β-lactamase (ESBL) genes in Enterobacteriaceae such as Escherichia coli or Klebsiella spp is a major challenge to modern medical practice. Carbapenems are the treatment of choice for serious infections caused by ESBL producers; however, carbapenem resistance has increased globally. ESBL producers might be susceptible to β-lactam-β-lactamase inhibitor (BLBLI) combination antibiotics such piperacillin-tazobactam or amoxicillin-clavulanate. These drugs are frequently avoided in serious infections caused by ESBL producers because of the inoculum effect in-vitro (especially for piperacillin-tazobactam), animal data suggesting inferior efficacy when compared with carbapenems, concerns about pharmacokinetic-pharmacodynamic drug target attainment with standard doses, and poor outcomes shown in some observational studies. Prospective cohort data and a meta-analysis suggest that BLBLIs are non-inferior to carbapenems in the treatment of bloodstream infections caused by ESBL producers. We examine why BLBLIs are perceived as inferior in the treatment of infection with ESBL producers, and discuss data that suggest these concerns might not be strongly supported by clinical evidence.

Study of family physicians' practices in case of urinary tract infections caused by enterobacteriaceae secreting extended-spectrum-beta-lactamase

INTRODUCTION

Urinary tract infections caused by enterobacteriaceae secreting extended-spectrum beta-lactamase (EESBL) is an issue for most family physicians. The aim of our study was to evaluate their practice in case of EESBL discovered after urinalysis and culture (U/C).

MATERIAL AND METHODS

This epidemiological and retrospective study was conducted from the January 1, to December 31, 2012, in 5 laboratories of Savoie and Isere. Results of U/C prescribed by family physicians and positive for EESBL were collected. The data collected with questionnaires, concerned characteristics of the infection, antibiotic treatment adequateness, the implementation of specific hygiene measures, and risk factors for EESBL infection.

RESULTS

One hundred and three U/C out of 19,494 were considered, and 56 questionnaires were collected. The rate of EESBL positive U/C was 0.60%. The antibiotic treatment was adequate for 35 patients (62.5%). Specific hygiene measures were implemented for 22 patients (32.3%). Both antibiotic treatment and specific hygiene measures were initiated for 13 patients (23.2%). Fourteen cases of community-acquired infections (25%) were reported. Five patients (8.9%) had traveled to an endemic zone in the previous 6 months.

CONCLUSION

The concomitant initiation of both antibiotic treatment and specific hygiene measures in case of U/C positive for EESBL is insufficient when managed by family physicians. It could be improved by offering tools for the management of these infections, by developing EESBL networks between hospital and family physicians, and epidemiological surveillance in community settings.

Complete nucleotide sequences of two NDM-1-encoding plasmids from the same sequence type 11 Klebsiella pneumoniae strain

The sequence type 11 Klebsiella pneumoniae strain Kpn-3002cz was confirmed to harbor two NDM-1-encoding plasmids, pB-3002cz and pS-3002cz. pB-3002cz (97,649 bp) displayed extensive sequence similarity with the blaNDM-1-carrying plasmid pKPX-1. pS-3002cz (73,581 bp) was found to consist of an IncR-related sequence (13,535 bp) and a mosaic region (60,046 bp). A 40,233-bp sequence of pS-3002cz was identical to the mosaic region of pB-3002cz, indicating the en bloc acquisition of the NDM-1-encoding region from one plasmid by the other.

Colistin resistance superimposed to endemic carbapenem-resistant Klebsiella pneumoniae: a rapidly evolving problem in Italy, November 2013 to April 2014

Consecutive non-replicate clinical isolates (n=191) of carbapenem non-susceptible Enterobacteriaceae were collected from 21 hospital laboratories across Italy from November 2013 to April 2014 as part of the European Survey on Carbapenemase-producing Enterobacteriaceae (EuSCAPE) project. Klebsiella pneumoniae carbapenemase-producing K. pneumoniae (KPC-KP) represented 178 (93%) isolates with 76 (43%) respectively resistant to colistin, a key drug for treating carbapenamase-producing Enterobacteriaceae. KPC-KP colistin-resistant isolates were detected in all participating laboratories. This underscores a concerning evolution of colistin resistance in a setting of high KPC-KP endemicity.

A pseudo-outbreak due to Acinetobacter species (GIM-1) contamination of the pneumatic transport system of a Large University Hospital

OBJECTIVE

To establish the source and contamination routes resulting in positive clinical and surveillance microbiological cultures with carbapenem-resistant, GIM-1 metallo-β-lactamase-positive Acinetobacter pitii and Acinetobacter radioresistens from 21 patients in 8 departments.

DESIGN

Retrospective, descriptive study.

SETTING

A 1,300-bed tertiary care academic medical facility consisting of 90 buildings linked by a pneumatic transport system (PTS).

METHODS

Microbiological workup of the cluster strains included matrix-assisted laser desorption/ionization time-of-flight species identification, phenotypic carbapenemase tests, polymerase chain reaction-based genotyping of carbapenemase, and pulsed-field gel electrophoresis. Outbreak management procedures were employed according to institutional regulations.

RESULTS

The rarity of GIM-1 Acinetobacter species in the hospital and region, the lack of epidemiological links between patients, and the fact that in some patients the apparent colonization was clearly nonnosocomial prompted the suspicion of a pseudo-outbreak. Numerous environmental cultures were positive for GIM-1-positive Acinetobacter (including archived sample requisition forms, PTS capsules, cultures from line-diverter and dispenser stations, and sterilized transport capsules following PTS delivery). Moreover, it was observed that condensation fluid from subterranean PTS tubing resulted in water entry in PTS capsules, possibly conferring specimen contamination. After extensive system disinfection, environmental surveys of the PTS were negative, and no further positive patient specimens were encountered.

CONCLUSIONS

This is the first report of a PTS-associated pseudo-outbreak. The large number of falsely positive patient-related specimens in conjunction with the potential hazard of airborne and contact spread of multidrug-resistant microorganisms (in this case, GIM-1 carbapenem-resistant Acinetobacter species) underscores the need for implementation of infection control-based monitoring and operating procedures in a hospital PTS.

Clinical spectrum of urine cultures positive for ESBL-producing Escherichia coli in hospitalized patients and impact on antibiotic use

OBJECTIVE

We wanted to describe the clinical features associated with urinalysis positive for ESBL-producing Escherichia coli and their impact on antibiotic use.

METHODS

We performed a prospective observational study in 13 French hospitals of the Paris area for 3 consecutive months. We included all patients with urine cultures positive for ESBL-producing E. coli.

RESULTS

One hundred and seventeen of the 218 patients (54%) presented with asymptomatic bacteriuria, 31 (14%) with cystitis, and 70 (32%) with a parenchymal infection. Nineteen patients with asymptomatic bacteriuria (16%) received antibiotics. Forty-one with parenchymal infections (59%) received a carbapenem. A carbapenem alternative could have been used in every patient treated with a carbapenem, according to antibiotic susceptibility testing results.

CONCLUSIONS

Urinary tract infections accounted for 46% of E. coli ESBL positive urinalysis. Fifty percent of parenchymal infections were treated with a carbapenem.

Evaluation of clonality and carbapenem resistance mechanisms among Acinetobacter baumannii-Acinetobacter calcoaceticus complex and Enterobacteriaceae isolates collected in European and Mediterranean countries and detection of two novel β-lactamases, GES-22 and VIM-35

We evaluated doripenem-resistant Acinetobacter baumannii-Acinetobacter calcoaceticus complex (ACB; n = 411) and Enterobacteriaceae (n = 92) isolates collected from patients from 14 European and Mediterranean countries during 2009 to 2011 for the presence of carbapenemase-encoding genes and clonality. Following susceptibility testing, carbapenem-resistant (doripenem MIC, >2 μg/ml) isolates were screened for carbapenemases. New β-lactamase genes were expressed in a common background and susceptibility was tested. Class 1 integrons were sequenced. Clonality was evaluated by pulsed-field gel electrophoresis and multilocus sequence typing (Pasteur scheme). Relative expression of β-lactam intrinsic resistance mechanisms was determined for carbapenemase-negative Enterobacteriaceae. ACB and Enterobacteriaceae displayed 58.9 and 0.9% doripenem resistance, respectively. bla(OXA-23), bla(OXA-58), and bla(OXA-24/OXA-40) were detected among 277, 77, and 29 ACB, respectively (in 8, 6, and 5 countries). Ten Turkish isolates carried bla(GES-11) or bla(GES-22). GES-22 (G243A and M169L mutations in GES-1) had an extended-spectrum β-lactamase profile. A total of 33 clusters of ≥ 2 ACB isolates were observed, and 227 isolates belonged to sequence type 2/international clone II. Other international clones were limited to Turkey and Israel. Doripenem-resistant Enterobacteriaceae increased significantly (0.7 to 1.6%), and 15 blaKPC-2- and 22 blaKPC-3-carrying isolates, mostly belonging to clonal complexes 11 and 258, were observed. Enterobacteriaceae isolates producing OXA-48 (n = 16; in Turkey and Italy), VIM-1 (n = 10; in Greece, Poland, and Spain), VIM-26 (n = 1; in Greece), and IMP-19, VIM-4, and the novel VIM-35 (n = 1 each from Poland) were detected. VIM-35 had one substitution compared to VIM-1 (A235T) and a similar susceptibility profile. One or more resistance mechanisms were identified in 4/6 carbapenemase-negative Enterobacteriaceae. This broad evaluation confirms results from country-specific surveys and shows a highly diverse population of carbapenemase-producing ACB and Enterobacteriaceae in Europe and Mediterranean countries.

Burden of carbapenem-resistant organisms in the Frankfurt/Main Metropolitan Area in Germany 2012/2013 - first results and experiences after the introduction of legally mandated reporting

BACKGROUND

The federal state of Hesse, Germany, introduced a laboratory-based reporting scheme for carbapenem-resistant organisms (CROs).

METHOD

The results of the first year of mandated reporting of CROs from April 2012 through March 2013 to the Public Health Authority of Frankfurt/Main, responsible for a population of 700,000 inhabitants, are described.

RESULTS

Within a period of 12 months 243 CROs were notified to the health authority. Of these 213 isolates had been reported from 16 of the 17 hospitals in Frankfurt/Main, 6 from ambulatory settings and 24 from clinics outside of Frankfurt/Main. Mean incidence rate per 1,000 patient days in hospitals was 0.138 (range 0.02-0.28).

CONCLUSION

In Frankfurt/Main almost all hospitals have reported CROs in the study period though the frequency of isolation varies strongly and many facilities only report CROs sporadically. Molecular data indicate a high diversity of different carbapenemases. Autochthonous transmission must be assumed despite the absence of major outbreaks. Rapid and coordinated efforts by clinicians and health departments are crucial to control the spread of CRO infections. The mandatory reporting scheme provides important data to guide the implementation of preventive measures.

Emergence of carbapenemase-producing Gram-negative bacteria in Saint Petersburg, Russia

The emergence and spread of carbapenemase-producing Gram-negative bacteria represents a serious public health concern. Here we show that of 477 Gram-negative isolates collected from 18 hospitals between November 2011 and February 2013 in Saint Petersburg (Russia), minimum inhibitory concentrations (MICs) were greater than the European Committee on Antimicrobial Susceptibility Testing (EUCAST) epidemiological cut-off value of at least one carbapenem antibiotic in 101 isolates (21.2%). The bla(NDM-1) gene was detected by PCR in 17 Klebsiella pneumoniae and 1 Acinetobacter nosocomialis isolate. Multilocus sequence typing (MLST) revealed that all NDM-1-producing K. pneumoniae isolates belonged to sequence type 340 (ST340) and harboured genes encoding additional β-lactamases; presence of the bla(CTX-M-1-like) gene correlated with aztreonam resistance, whilst its absence correlated with susceptibility. The epidemiological situation in Saint Petersburg can be assessed as regional spread of NDM-1-producers. The bla(KPC-2) gene was detected in two K. pneumoniae isolates (ST258 and ST273) and one Enterobacter cloacae isolate. Two E. cloacae isolates harboured the bla(VIM-4) gene, and one K. pneumoniae (ST395) isolate harboured the bla(OXA-48) gene. In NDM-1-producers, MICs of biapenem were the lowest compared with those of other carbapenems. Most isolates were susceptible to tigecycline and polymyxin, except for one K. pneumoniae isolate that was found to be polymyxin-resistant and one E. cloacae isolate that was tigecycline-resistant. Only one patient with a urinary tract infection caused by KPC-2-producing K. pneumoniae had a history of travel abroad (Southeast Asia). Thus, there is an actual threat of the emergence of an alarming endemic situation with NDM-1-producers in Saint Petersburg.

Comparison of phenotypic methods for the detection of carbapenem non-susceptible Enterobacteriaceae

Background

Multidrug resistance and, in particular, carbapenem resistance is spreading worldwide at an alarming rate, comprehending a variety of bacterial species and causing both nosocomial and community acquired outbursts. Early and efficient detection of infected patients or colonized carriers are mandatory steps in infection control and prevention of multidrug resistance diffusion. The latest EUCAST guidelines for detection of carbapenemase-producing Enterobacteriaceae have set low clinical breakpoints to ensure the maximum detection sensitivity of positive samples. Current workflows involve an initial screening step for species and resistance pattern detection, followed by phenotypic and/or genotypic confirmation. The aim of the present study was to assess the efficiency of six widely used and validated phenotypic assays for the detection of carbapenemases/AmpC in Enterobacteriaceae, to estimate the best workflow in the routine characterization of Enterobacteriaceae isolates.

Methods

A panel of 108 non-repetitive Enterobacteriaceae isolates with reduced susceptibility to carbapenems was analyzed by means of 1) Modified Hodge Test, 2) Metallo Beta Lactamase Etest, 3) Double disk test with EDTA, 4) Rosco Diagnostica KPC and MBL confirm kit (RDCK™), 5) AmpC Etest and 6) Cloxacillin inhibition test. Confirmation and validation of results was achieved by genotypic analysis.

Results

The most accurate identification of resistance determinants was obtained with the combined disc test (Rosco Diagnostica KPC and MBL confirm kit) which had to be coupled with the cloxacillin inhibition test for correct detection of AmpC enzymes. However, in general, phenotypic tests failed to characterize isolates harboring multiple carbapenem resistance determinants, which were successfully assessed only by PCR-based analysis.

Conclusions

To detect and control the spread of pathogens with complicated resistance patterns, both optimized phenotypic analysis (i.e. Rosco Diagnostica KPC and MBL confirm kit coupled with the cloxacillin inhibition test) and genotypic assays are recommended in the routine diagnostic of clinical laboratories.

[The threat of the carbapenemase-producing enterobacteriaceae in Spain: positioning report of the SEIMC study groups, GEIH and GEMARA]

The emergence and spread of carbapenemase-producing Enterobacteriaceae (CPE), as the current paradigm of extensive drug-resistance and multi-drug resistance to antibiotics, is a serious threat to patient health and public health. The increase in OXA-48- and VIM-1-producing Klebsiella pneumoniae isolates represents the greatest impact of CPE in Spain. This evidence has lead the members of a representative panel of the Spanish Study Groups of Nosocomial Infections and Mechanisms of Action and Resistance to Antimicrobials of the Spanish Society of Clinical Microbiology and Infectious Diseases (GEIH/GEMARA-SEIMC) to make a position statement expressing the need for: (i) definitive and coordinated action by all health professionals and authorities involved, and (ii) an adaptation of health systems to facilitate their early control and minimize their impact.

Introduction of highly resistant bacteria into a hospital via patients repatriated or recently hospitalized in a foreign country

We describe the prevalence of carriage and variables associated with introduction of highly drug-resistant microorganisms (HDRMO) into a French hospital via patients repatriated or recently hospitalized in a foreign country. The prevalence of HDRMO was 11% (15/132), with nine carbapenamase-producing Enterobacteriaceae, nine carbapenem-resistant Acinetobacter baumannii and six glycopeptide-resistant enterococci. Half of the admitted patients (63/132, 48%) were colonized with extended spectrum beta-lactamase-producing Enterobacteriaceae (ESBLPE). Among the four episodes with secondary cases, three involved A. baumannii.

Detection of carbapenemase-producing enterobacteriaceae in the baltic countries and st. Petersburg area

The spread of carbapenemase-producing Enterobacteriaceae is a global problem; however, no exact data on the epidemiology of carbapenemase in the Baltic countries and St. Petersburg area is available. We aimed to evaluate the epidemiology of carbapenemase-producing Escherichia coli and Klebsiella pneumoniae in the Baltic States and St. Petersburg, Russia, and to compare the different methods for carbapenemase detection. From January to May 2012, all K. pneumoniae (n = 1983) and E. coli (n = 7774) clinical isolates from 20 institutions in Estonia, Latvia, Lithuania, and St. Petersburg, Russia were screened for carbapenem susceptibility. The IMP, VIM, GIM, NDM, KPC, and OXA-48 genes were detected using real-time PCR and the ability to hydrolyze ertapenem was determined using MALDI-TOF MS. Seventy-seven strains were found to be carbapenem nonsusceptible. From these, 15 K. pneumoniae strains hydrolyzed ertapenem and carried the bla_NDM gene. All of these strains carried integron 1 and most carried integron 3 as well as genes of the CTX-M-1 group. No carbapenemase-producing E. coli or K. pneumoniae strains were found in Estonia, Latvia, or Lithuania; however, NDM-positive K. pneumoniae was present in the hospital in St. Petersburg, Russia. A MALDI-TOF MS-based assay is a suitable and cost-effective method for the initial confirmation of carbapenemase production.

Spread of NDM-1-producing Enterobacteriaceae in a neonatal intensive care unit in Istanbul, Turkey

Twenty-two consecutive carbapenem-resistant enterobacterial isolates were recovered from patients hospitalized between January and April 2013 in different units at a university hospital in Istanbul, Turkey. These were Klebsiella pneumoniae isolates producing the carbapenemases OXA-48, NDM-1, and KPC-2, Enterobacter cloacae isolates producing NDM-1, and Escherichia coli isolates producing OXA-48. Most of the OXA-48-producing K. pneumoniae and all the NDM-1-producing E. cloacae were clonally related. The NDM-1-producing E. cloacae isolates recovered from a single neonatal intensive care unit corresponded to a single cluster, highlighting the spread of that clone in that setting.

An emerging public health problem: acquired carbapenemase-producing microorganisms are present in food-producing animals, their environment, companion animals and wild birds

Worldwide, the emergence and global spread of microorganisms with acquired carbapenemases is of great concern. The reservoirs for such organisms are increasing, not only in hospitals, but also in the community and environment. A new and important development is the presence of such organisms in livestock, companion animals and wildlife. During the last three years, carbapenemase-producing Escherichia coli, Salmonella spp. (VIM-1 producers) and Acinetobacter spp. (producing OXA-23 and NDM-1) in livestock animals (poultry, cattle and swine) and their environment have been reported. In addition, the isolation of NDM-1-producing E. coli, OXA-48 in E. coli and Klebsiella pneumoniae or OXA-23 in Acinetobacter spp. from companion animals (cats, dogs or horses) has also been observed. Other reports have described the presence of NDM-1-producing Salmonella isolated from wild birds, as well as OXA-23-like-producing Acinetobacter baumannii in ectoparasites. However, until now carbapenemase producers from foods have not been detected. For humans in contrast carbapenem-producing Salmonella isolates are increasingly reported. The real prevalence of carbapenemase-encoding genes in zoonotic bacteria or commensals from animals is unknown. Consequently, there is a need for intensified surveillance on the occurrence of carbapenemase-producing bacteria in the food chain and other animal sources in order to assist in the formulation of measures to prevent their potential spread.

Outbreak caused by NDM-1- and RmtB-producing Escherichia coli in Bulgaria

Twelve consecutive carbapenem-resistant Escherichia coli isolates were recovered from patients (infection or colonization) hospitalized between March and September 2012 in different units at a hospital in Bulgaria. They all produced the carbapenemase NDM-1 and the extended-spectrum-β-lactamase CTX-M-15, together with the 16S rRNA methylase RmtB, conferring high-level resistance to all aminoglycosides. All those isolates were clonally related and belonged to the same sequence type, ST101. In addition to being the first to identify NDM-producing isolates in Bulgaria, this is the very first study reporting an outbreak of NDM-1-producing E. coli in the world.

OXA-48 carbapenemase-producing Salmonella enterica serovar Kentucky isolate of sequence type 198 in a patient transferred from Libya to Switzerland

Here, we report a case of OXA-48-producing Salmonella enterica serovar Kentucky of sequence type 198 (ST198) from perianal screening cultures of a patient transferred from Libya to Switzerland. The blaOXA-48 gene was carried by Tn1999.2 and located on an ∼60-kb IncL/M plasmid. This Salmonella strain also possessed the blaVEB-8, aac(6)-Ib, tet(A), sul1, and mphA resistance genes and substitutions in GyrA (Ser83Phe and Asp87Asn) and ParC (Ser80Ile). This finding emphasizes that prompt screening strategies are essential to prevent the dissemination of carbapenemase producers imported from countries where they are endemic.

The global challenge of carbapenem-resistant Enterobacteriaceae in transplant recipients and patients with hematologic malignancies

Carbapenem-resistant Enterobacteriaceae (CRE) are emerging global pathogens. The spread of CRE to transplant recipients and patients with hematologic malignancies has ominous implications. These patients rely on timely, active antibacterial therapy to combat gram-negative infections; however, recommended empirical regimens are not active against CRE. Approximately 3%-10% of solid organ transplant (SOT) recipients in CRE-endemic areas develop CRE infection, and the infection site correlates with the transplanted organ. Mortality rates associated with CRE infections approach 40% in SOT recipients and 65% in patients with hematologic malignancies. Given that the current antimicrobial armamentarium to combat CRE is extremely limited, a multifaceted approach that includes antimicrobial stewardship and active surveillance is needed to prevent CRE infections in immunocompromised hosts. Improving outcomes of established infections will require the use of risk factor-based prediction tools and molecular assays to more rapidly administer CRE-active therapy and the development of new antimicrobial agents with activity against CRE.

Escherichia coli in Europe: an overview

Escherichia coli remains one of the most frequent causes of several common bacterial infections in humans and animals. E. coli is the prominent cause of enteritis, urinary tract infection, septicaemia and other clinical infections, such as neonatal meningitis. E. coli is also prominently associated with diarrhoea in pet and farm animals. The therapeutic treatment of E. coli infections is threatened by the emergence of antimicrobial resistance. The prevalence of multidrug-resistant E. coli strains is increasing worldwide principally due to the spread of mobile genetic elements, such as plasmids. The rise of multidrug-resistant strains of E. coli also occurs in Europe. Therefore, the spread of resistance in E. coli is an increasing public health concern in European countries. This paper summarizes the current status of E. coli strains clinically relevant in European countries. Furthermore, therapeutic interventions and strategies to prevent and control infections are presented and discussed. The article also provides an overview of the current knowledge concerning promising alternative therapies against E. coli diseases.

Carbapenem-Resistant Enterobacteriaceae: Laboratory Detection and Infection Control Practices

Over the past decade, carbapenem-resistant Enterobacteriaceae (CRE) have become one of the most challenging problems in infectious diseases. Fast and accurate detection of carbapenem resistance is crucial for guiding the treatment of the individual patient as well as for instituting proper infection control measures to limit the spread of the organism. Currently there are no consensus recommendations for screening, detection and confirmation of CRE either on the clinical or the laboratory side. In infection control, data from controlled intervention studies is largely missing and most recommendations have been deduced from outbreak situations. From the available limited evidence, infection control guidelines have been developed in most countries at national, regional and hospital levels. The aim of this review is to summarize the currently available laboratory methods and infection control options.