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The article explores the genetic diversity and taxonomic position of Oophaga vicentei, a poison frog species found in Panama. The study focuses on a unique color morph of O. vicentei characterized by pale yellow dots on a dark brown background. DNA sequencing was used to determine the relationships and genetic diversity of this population. The results show that the unique color morph forms a distinct group within the species. The article emphasizes the need for further research to fully understand the phylogeny of this species complex and suggests potential investigations into color polymorphism and microhabitat preferences. The study was conducted with proper ethical approval and funding. [Extracted from the article]

Abstract: Objective: The Greek Public Servants’ Health Care Organization aiming to organize, monitor, and enhance the health care services provided to 1,500,000 public servants decided to respond to the national alert of the economic crisis through the reduction of costs caused by diagnostic tests (€300,000,000 claims for 2008), to improve working conditions of contracted physicians and laboratories, and to enhance services provided to insured members. In September 2010, the Greek Public Servants’ Health Care Organization initiated a pilot project that electronically records the prescription process of the diagnostic tests, which is Web-based, is open source, and was provided for free to the contracted physicians and diagnostic centers. Methods: In this article, we present some interesting findings resulting from the implementation of the pilot electronic referral project by examining a 9-month period. Results: Fifty-eight percent of the physicians had the necessary equipment for the operation of the system, more than 3600 physicians used it, 17,495 public servants had been served through the system, and 178,456 paraclinical examinations had been prescribed with a cost of €1,394,980. In addition, the analysis revealed that the implementation of an electronic referral system could provide significant benefits, such as a faster referral process, valid and coherent information, minimization of the risk of misinterpreting the electronic referral due to illegibility of handwriting, and improvement in quality of services. Conclusions: The Greek electronic referral system was one of the first attempts toward creating the basis of a society of transparency and cost control. The lessons learnt from this article should not be ignored in the process of redesigning and improving the electronic referral system for Greece. [Copyright &y& Elsevier]

The demands of health system are set to evolve based on patients needs and thus, healthcare managers and clinicians require decision making tools that will support them in providing better services to patients. Currently, the non-integrated nature of healthcare Information Systems (IS) is strongly associated with both a reduction in the outcome of care as well as the many medical errors that occur. Recent reports show that around 23,360 people per annum die in UK due to problems related to the medical errors and mainly caused by the non-integrated nature of the healthcare information systems. Development of an integrated JT infrastructure across the healthcare sector will result in enhanced services provided to all actors and will protect and improve human lives. During the last years, much emphasis has been given on Enterprise Application Integration (EAT) technology to bridge together disparate and autonomous systems. EAI is underutilised in the healthcare sector, with many studies showing that resistance to change and lack of awareness are among the main reasons associated with this phenomenon. Although the benefits of EAI are well analysed in literature, there is a need to understand and explain these benefits in the area of healthcare. This is of high importance since it will be easier to address the resistance to change and speed up the adoption of EAI. This paper proposes an actor-oriented approach to identify, analyse and classify benefits associated with the application of EAI in healthcare. The authors introduce a novel taxonomy to classify the EAT benefits and combine the proposed actor-oriented approach with an existing classification for EAT benefits. In doing so, they enhance the level of analysis and allow researchers and managers to better realise the benefits derived from the use of EAI in healthcare. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the performance of the BCID2 FilmArray panel in relation to blood culture. 162 positive blood cultures were subjected to both classical microbiology methods and the FilmArray nested multiplex PCR. The BCID2 panel showed 96.7% sensitivity, 99% specificity and 99% accuracy., Competing Interests: Declaration of competing interest There is no any conflict of interest, (Copyright © 2024 Elsevier Inc. All rights reserved.)

The present study aimed to determine the resistance mechanisms and clonal relationships among vancomycin-resistant Enterococci (VRE) isolated in AHEPA University Hospital during the pandemic year 2021. Overall, 140 clinical VRE were isolated during the study period and 44 were randomly selected for molecular analysis. A multiplex PCR was employed to detect vancomycin resistance genes (vanA, vanB, vanC, vanD, vanE, vanG) using specific primers. Additionally, pulsed-field gel electrophoresis (PFGE) was performed to assess the clonal relatedness of the selected isolates. The multiplex PCR showed that 36 of the 44 studied strains (81.9%) harbored the vanA gene whereas, 7 of 44 (15.9%) co-harbored the vanA and vanB resistance genes; one isolate had a negative PCR result. PFGE analysis unveiled 37 distinct electrophoretic patterns among the 44 VRE isolates with a similarity threshold of 75%. These patterns were clustered into 4 distinct branches. Our findings indicate a polyclonal distribution of vanA genes among the studied isolates and the notable concomitant presence of vanA/vanB genotypes. Furthermore, these results highlight the worsening that took place during the COVID-19 pandemic period regarding antibiotic resistance rates, underscoring the imperative need for stringent infection control measures and active surveillance.

Carbapenemase-producing Pseudomonas aeruginosa strains present a specific geographical distribution regarding the type of carbapenemase-encoding genes that they harbor. For more than twenty years, VIM-type enzymes were the only major carbapenemases that were detected among P. aeruginosa isolates in Greece until the emergence of NDM-1-encoding P. aeruginosa in early 2023. In the present study, we present the rapid reversal of the carbapenemase-producing P. aeruginosa epidemiology from bla VIM - to bla NDM -harbouring isolates that occurred in our hospital since then. Between January 2023 and February 2024, 139 isolates tested positive for carbapenemase production with the NG-Test CARBA 5 immunochromatographic assay. Eight isolates were processed with the Hybrispot antimicrobial resistance direct flow chip molecular assay, and the first NDM-producing isolate was further analyzed through whole genome sequencing and bioinformatics analysis. Multiple resistance genes were detected by molecular techniques in accordance with the extensively drug-resistant phenotype. The isolate that was subjected to whole-genome sequencing belonged to the P. aeruginosa high-risk clone ST308, and the bla NDM was located in the chromosome in accordance with previously reported data. During the study period, NDM-producing isolates were increasingly detected, and only five months after their emergence, they overcame VIM producers. Our results indicate the potential of this new clone to spread rapidly and predominate within healthcare institutions, further restricting the already limited treatment options.

Objectives: This study aims to detect the prevalence and specific characteristics of Clostridioides difficile infection (CDI) during the COVID-19 pandemic., Methods: In this retrospective observational study, conducted in a tertiary hospital in Greece between May 2021 and October 2022, patients with CDI from COVID-19 and Internal Medicine wards were enrolled and compared based on epidemiological and disease-associated data., Results: In total, 4322 patients were admitted, and 435 samples for CDI were analyzed, with 104/435 (23.9 %) sample positivity and 2.4 % prevalence. We observed an increased prevalence of CDI compared to the beginning of the COVID-19 pandemic (prevalence = 1.7 %, p = 0.003). 35.6 % of the CDI patients were hospitalized in the COVID-19 ward and 64.4 % in the Internal Medicine ward. COVID-19 patients were younger (p = 0.02) with a lower Charlson Comorbidity Index (CCI) compared to the Internal Medicine ward patients (p < 0.001). With regards to the origin of CDI cases, in the Internal Medicine ward, 68.7 % presented with Hospital-Onset CDI, 17.9 % with Community Onset-Healthcare Associated CDI and 13.4 % with Community Associated CDI, while in the COVID-19 ward, the respective percentages were 86.5 %, 5.4 % and 8.1 %. Finally, there was an increased CDI-related CFR (Case Fatality Ratio) in the Internal Medicine ward compared to the COVID-19 ward (28.4 % vs. 5.4 %, p = 0.001)., Conclusions: Increased CDI prevalence and testing were observed compared to the beginning of the COVID-19 pandemic. Lower CDI-related CFR was observed in patients with COVID-19, which may be credited to the patients' significantly lower median age and CCI, as well as to the majority of deaths being due to respiratory failure., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Ochrobactrum intermedium is recognized as a rare emerging opportunistic pathogen mostly related with bloodstream infections. In this report, we describe the first clinical case of pneumonia due to O. intermedium. The case involved a 71-year old tetraplegic man hospitalized for vertebral fractures after falling from a ladder., Competing Interests: All authors report no conflicts of interest relevant to this article., (© 2024 The Authors.)

NDM carbapenemase-encoding genes disseminate commonly among Enterobacterales through transferable plasmids carrying additional resistance determinants. Apart from the intra-species dissemination, the inter-species exchange of plasmids seems to play an additional important role in the spread of bla NDM . We here present the genetics related to the isolation of three species ( Klebsiella pneumoniae , Proteus mirabilis , and Morganella morganii ) harboring the bla NDM-1 gene from a single patient in Greece. Bacterial identification and antimicrobial susceptibility testing were performed using the Vitek2. Whole genome sequencing and bioinformatic tools were used to identify resistance genes and plasmids. Bla NDM-1 harboring plasmids were found in all three isolates. Moreover, the plasmid constructs of the respective incomplete or circular contigs showed that the bla NDM-1 and its neighboring genes form a cluster that was found in all isolates. Our microbiological findings, together with the patient's history, suggest the in vivo transfer of the bla NDM-1 -containing cluster through three different species in a single patient.

The incidence of multidrug-resistant (MDR) bloodstream infections (BSIs) is associated with high morbidity and mortality. Little evidence exists regarding the epidemiology of BSIs and the use of appropriate empirical antimicrobial therapy in endemic regions. Novel diagnostic tests (RDTs) may facilitate and improve patient management. Data were assessed from patients with MDR Gram-negative bacteremia at a university tertiary hospital over a 12-month period. In total, 157 episodes of MDR Gram-negative BSI were included in the study. The overall mortality rate was 50.3%. Rapid molecular diagnostic tests were used in 94% of BSI episodes. In univariate analysis, age (OR 1.05 (95% CI 1.03, 1.08) p < 0.001), Charlson Comorbidity Index (OR 1.51 (95% CI 1.25, 1.83) p < 0.001), procalcitonin ≥ 1(OR 3.67 (CI 95% 1.73, 7.79) p < 0.001), and monotherapy with tigecycline (OR 3.64 (95% CI 1.13, 11.73) p = 0.030) were the only factors associated with increased overall mortality. Surprisingly, time to appropriate antimicrobial treatment had no impact on mortality. MDR pathogen isolation, other than Klebsiella pneumoniae and Acinetobacter baumanii , was associated with decreased mortality (OR 0.35 (95% CI 0.16, 0.79) p = 0.011). In multivariate analysis, the only significant factor for mortality was procalcitonin ≥ 1 (OR 2.84 (95% CI 1.13, 7.11) p = 0.025). In conclusion, in an endemic area, mortality rates in MDR BSI remain notable. High procalcitonin was the only variable that predicted death. The use of rapid diagnostics did not improve mortality rate.

The prompt detection of carbapenemases among Gram-negative bacteria isolated from patients' clinical infection samples and surveillance cultures is important for the implementation of infection control measures. In this context, we evaluated the effectiveness of replacing phenotypic tests for the detection of carbapenemase producers with the immunochromatographic Carbapenem-Resistant K.N.I.V.O. Detection K-Set lateral flow assay (LFA). In total, 178 carbapenem-resistant Enterobacterales and 32 carbapenem-resistant Pseudomonas aeruginosa isolated in our hospital were tested with both our established phenotypic and molecular testing procedures and the LFA. The Kappa coefficient of agreement for Enterobacterales was 0.85 ( p < 0.001) and 0.6 ( p < 0.001) for P. aeruginosa . No major disagreements were observed and notably, in many cases, the LFA detected more carbapenemases than the double meropenem disc test, especially regarding OXA-48 in Enterobacterales and VIM in P. aeruginosa . Overall, the Carbapenem-Resistant K.N.I.V.O. Detection K-Set was very effective and at least equivalent to the standard procedures used in our lab. However, it was much faster as it provided results in 15 min compared to a minimum of 18-24 h for the phenotypic tests.

Mucormycosis has emerged as a group of severe infections mainly in immunocompromised patients. We analysed the epidemiology of mucormycosis in Greece in a multicentre, nationwide prospective survey of patients of all ages, during 2005-2022. A total of 108 cases were recorded. The annual incidence declined after 2009 and appeared stable thereafter, at 0.54 cases/million population. The most common forms were rhinocerebral (51.8%), cutaneous (32.4%), and pulmonary (11.1%). Main underlying conditions were haematologic malignancy/neutropenia (29.9%), haematopoietic stem cell transplantation (4.7%), diabetes mellitus (DM) (15.9%), other immunodeficiencies (23.4%), while 22.4% of cases involved immunocompetent individuals with cutaneous/soft-tissue infections after motor vehicle accident, surgical/iatrogenic trauma, burns, and injuries associated with natural disasters. Additionally, DM or steroid-induced DM was reported as a comorbidity in 21.5% of cases with various main conditions. Rhizopus (mostly R. arrhizus ) predominated (67.1%), followed by Lichtheimia (8.5%) and Mucor (6.1%). Antifungal treatment consisted mainly of liposomal amphotericin B (86.3%), median dose 7 mg/kg/day, range 3-10 mg/kg/day, with or without posaconazole. Crude mortality was 62.8% during 2005-2008 but decreased significantly after 2009, at 34.9% ( p = 0.02), with four times fewer haematological cases, fewer iatrogenic infections, and fewer cases with advanced rhinocerebral form. The increased DM prevalence should alert clinicians for timely diagnosis of mucormycosis in this patient population.

Streptococcus pyogenes is responsible for various clinical manifestations in patients of all ages worldwide. Worryingly, an increase in antibiotic resistance rates of S. pyogenes has been observed in many countries. In the present study, 6-year data are presented regarding the antibiotic resistance rates of S. pyogenes in our hospital. During this period, a total of 52 S. pyogenes isolates were recovered from 52 patients and antimicrobial susceptibility testing was performed for 49 isolates. All were susceptible to penicillin, ampicillin, cefotaxime, ceftriaxone, linezolid, moxifloxacin, rifampicin, vancomycin, teicoplanin, and tigecycline. Erythromycin and clindamycin resistance rates were 20.4% and 18.8% respectively. Resistance rates to tetracycline were 40.8%, to chloramphenicol 6.9%, and to levofloxacin 2%. Since macrolides are recommended as an alternative treatment in case of allergy to β-lactams, the high macrolide resistance rates are causing concern. Because different phenotypic antimicrobial patterns for S. pyogenes have been observed in different geographic areas, epidemiological data is of considerable value for the appropriate treatment choices.

Polymyxins are commonly used as the last resort for the treatment of MDR Acinetobacter baumannii and Klebsiella pneumoniae nosocomial infections; however, apart from the already known toxicity issues, resistance to these agents is emerging. In the present study, we assessed the in vitro synergistic activity of antimicrobial combinations against carbapenem-resistant and colistin-resistant A. baumannii and K. pneumoniae in an effort to provide more options for their treatment. Two hundred A. baumannii and one hundred and six K. pneumoniae single clinical isolates with resistance to carbapenems and colistin, recovered between 1 January 2021 and 31 July 2022,were included. A. baumannii were tested by the MIC test strip fixed-ratio method for combinations of colistin with either meropenem or rifampicin or daptomycin. K. pneumoniae were tested for the combinations of colistin with meropenem and ceftazidime/avibactam with aztreonam. Synergy was observed at: 98.99% for colistin and meropenem against A. baumannii ; 91.52% for colistin and rifampicin; and 100% for colistin and daptomycin. Synergy was also observed at: 73.56% for colistin and meropenem against K. pneumoniae and; and 93% for ceftazidime/avibactam with aztreonam. The tested antimicrobial combinations presented high synergy rates, rendering them valuable options against A. baumannii and K. pneumoniae infections.

Aspergillus spp. isolated from non-BAL cultures of coronavirus disease 2019 (COVID-19)-associated pulmonary aspergillosis (CAPA) patients may reflect colonization rather than infection. Sera (n = 181) from 49 adult ICU CAPA patients (24 probable and 25 possible CAPA) with bronchial secretions (BS) culture positive for Aspergillus spp. were collected and tested for Aspergillus DNA detection by species-specific real-time PCR. Overall, 30/49 (61%) patients were PCR positive. BS culture/serum PCR agreement was moderate (21/30; 70%). Based on serum PCR positive patients, all CAPAs were due to A. fumigatus (80%), A. flavus (10%), and A. terreus (10%). No A. niger/A. nidulans or mixed infections were found despite positive BS cultures., (© The Author(s) 2022. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

Objectives: In this communication, we describe the emergence of the mcr-1 colistin resistance gene in a blaCTX-M-32 extended-spectrum-β-lactamase-producing Escherichia coli isolate recovered from a pediatric patient in Greece., Methods: Bacterial identification and antimicrobial susceptibility testing were performed with the VITEK2 automated system and broth microdilution. Detection of resistance genes, assignment to sequence type, in silico plasmid detection, and virulence factors were carried out using ResFinder, MLST 2.0, PlasmidFinder 2.1., and VirulenceFinder 2.0, respectively. PlasmidSPAdes v3.11.1 was used to assemble the plasmid contigs. The mcr-1.1-containing plasmid was analyzed for insertion sequence elements using ISfinder. Phylogenetically relevant sequences of the plasmid were identified using the Microbe BLASTN suite., Results: The microorganism was assigned to sequence type 48 and carried four plasmids of different incompatibility groups. The specific mcr-1.1 allele was located in a 32.722 bp plasmid belonging to the IncX4 group with no additional resistance genes., Conclusion: To the best of our knowledge, this is the first detection of mcr-1 in a human specimen in our country. A potential spread of mcr-1 in Greece is concerning because of the existing high rates of carbapenem resistance and colistin usage as a last resort regimen., Competing Interests: Competing interests None declared., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

We evaluated the in vitro activity of eravacycline and cefoperazone/sulbactam against 42 XDR and 58 PDR Acinetobacter baumannii isolates from blood and bronchoalveolar infections. The minimum and maximum MICs for eravacycline were 0.125 and 4 mg/L, respectively. The MIC50 was 2 mg/L and the MIC90 was 3 mg/L. The minimum and maximum MICs for cefoperazone/sulbactam were 24 and >256 mg/L, respectively. The MIC50 and MIC90 were both >256 mg/L. These novel agents were not adequate for the treatment of A. baumannii infections in our hospital and we recommend that mi- crobiology laboratories perform their own evaluations before including them in clinical practice.

Carbapenemase-producing Klebsiella pneumoniae (CPKP) emerged in Greece in 2002 and became endemic thereafter. Driven by a notable variability in the phenotypic testing results for carbapenemase production in K. pneumoniae isolates from the intensive care units (ICUs) of our hospital, we performed a study to assess the molecular epidemiology of CPKP isolated between 2016 and 2019 using pulse-field gel electrophoresis (PFGE) including isolates recovered from 165 single patients. We investigated the molecular relatedness among strains recovered from rectal surveillance cultures and from respective subsequent infections due to CPKP in the same individual (48/165 cases). For the optimal interpretation of our findings, we carried out a systematic review regarding the clonality of CPKP isolated from clinical samples in ICUs in Europe. In our study, we identified 128 distinguishable pulsotypes and 17 clusters that indicated extended dissemination of CPKP within the hospital ICU setting throughout the study period. Among the clinical isolates, 122 harbored KPC genes (74%), 2 harbored KPC+NDM (1.2%), 38 harbored NDM (23%), 1 harbored NDM+OXA-48 (0.6%), 1 harbored NDM+VIM (0.6%) and 1 harbored the VIM (0.6%) gene. Multiple CPKP strains in our hospital have achieved sustained transmission. The polyclonal endemicity of CPKP presents a further threat for the selection of pathogens resistant to last-resort antimicrobial agents.

Northern Greece was struck by an intense second COVID-19 (coronavirus disease 2019) epidemic wave during the fall of 2020. Because of the coinciding silent epidemic of multidrug-resistant organisms, the handling of COVID-19 patients became even more challenging. In the present study, the microbiological characteristics of bacteremias in confirmed cases of hospitalized COVID-19 patients were determined. Data from 1165 patients hospitalized between September and December 2020 were reviewed regarding the frequency of bloodstream infections, the epidemiology and the antibiotic susceptibility profiles of the causative bacteria. The hospital's antibiotic susceptibility data for all major nosocomial pathogens isolated from bacteremias of COVID-19 patients between September and December 2020 versus those between September and December 2019 were also compared. Overall, 122 patients developed bacteremia (10.47%). The average of time interval between hospitalization date and development of bacteremia was 13.98 days. Admission to ICU occurred in 98 out of 122 patients with an average stay time of 15.85 days and 90.81% in-hospital mortality. In total, 166 pathogens were recovered including 114 Gram-negative bacteria and 52 Gram-positive cocci. Acinetobacter baumannii was the most frequent ( n = 51) followed by Klebsiella pneumoniae ( n = 45) and Enterococcus faecium ( n = 31). Bacteremias in hospitalized COVID-19 patients were related with prolonged time of hospitalization and higher in-hospital mortality, and the isolated microorganisms represented the bacterial species that were present in our hospital before the COVID-19 pandemic. Worryingly, the antibiotic resistance rates were increased compared with the pre-pandemic era for all major opportunistic bacterial pathogens. The pandemic highlighted the need for continuous surveillance of patients with prolonged hospitalization., (© The Author(s) 2021. Published by Oxford University Press on behalf of FEMS.)

Changes in hospitals' daily practice due to COVID-19 pandemic may have an impact on antimicrobial resistance (AMR). We aimed to assess this possible impact as captured by the Greek Electronic System for the Surveillance of Antimicrobial Resistance (WHONET-Greece). Routine susceptibility data of 17,837 Gram-negative and Gram-positive bacterial isolates from blood and respiratory specimens of hospitalized patients in nine COVID-19 tertiary hospitals were used in order to identify potential differences in AMR trends in the last three years, divided into two periods, January 2018-March 2020 and April 2020-March 2021. Interrupted time-series analysis was used to evaluate differences in the trends of non-susceptibility before and after the changes due to COVID-19. We found significant differences in the slope of non-susceptibility trends of Acinetobacter baumannii blood and respiratory isolates to amikacin, tigecycline and colistin; of Klebsiella pneumoniae blood and respiratory isolates to meropenem and tigecycline; and of Pseudomonas aeruginosa respiratory isolates to imipenem, meropenem and levofloxacin. Additionally, we found significant differences in the slope of non-susceptibility trends of Staphylococcus aureus isolates to oxacillin and of Enterococcus faecium isolates to glycopeptides. Assessing in this early stage, through surveillance of routine laboratory data, the way a new global threat like COVID-19 could affect an already ongoing pandemic like AMR provides useful information for prompt action.

Ceftaroline is a novel cephalosporin able to bind to and inhibit PBP2a, and thus active against methicillin-resistant Staphylococcus aureus. In the present study we assessed the in vitro activity of ceftaroline and comparators against a large sample of methicillin-resistant and methicillin-susceptible S. aureus isolates collected at our hospital. Overall, both MRSA and MSSA isolates in our study were sensitive to ceftaroline, even though the MIC range was higher for MRSAs (0.12-2 mg/L against ≤0.06-0.5 mg/L for MSSAs). Our results indicate that ceftaroline may be considered a reliable alternative for the treatment of MRSA.

Co-infections have an unknown impact on the morbidity and mortality of the new clinical syndrome called coronavirus disease 2019 (COVID-19). The syndrome is caused by the new pandemic coronavirus SARS-CoV-2 and it is probably connected with severe traces in the elements of the immune system. Apart from possible Aspergillus infections, particularly in patients with acute respiratory distress syndrome (ARDS), other fungal infections could occur, probably more easily, due to the immunological dysregulation and the critical condition of these patients. Probiotic preparations of Saccharomyces are broadly used for the prevention of antibiotic-associated complications, especially in the intensive care units (ICU). On the other hand, Saccharomyces organisms are reported as agents of invasive infection in immunocompromised or critically ill patients. We report two cases of bloodstream infection by Saccharomyces in two patients hospitalised in the ICU, due to severe COVID-19, after Saccharomyces supplementation.

Objectives: A Pseudomonas aeruginosa clinical isolate that exhibited high-level carbapenem resistance and produced metallo-beta-lactamase (MBL) was recovered from a Greek patient. This study was conducted to determine the underlying mechanisms that conferred the carbapenem resistance phenotype., Methods: MICs were determined by Etest and Etest MBL. PCR assays were performed for identification of bla(VIM-type), other antibiotic resistance and efflux pump genes and mapping of class 1 integrons. Expression of efflux pump genes was quantified by real-time PCR. Nucleotide sequencing was used to determine the bla(VIM) allele. The location of the MBL allele was investigated by mating experiments, plasmid analysis and hybridization studies., Results: The isolate was highly carbapenem-resistant (MICs of imipenem and meropenem were 512 and 128 mg/L, respectively) and multidrug-resistant. It harboured the beta-lactamase genes bla(VIM-4) and bla(P1b) in a novel class 1 integron named InV4P1, and a second integron with aac(6')-Ib and bla(OXA-35) gene cassettes. The isolate was deficient in porin OprD and overexpressed efflux pumps MexAB-OprM and MexXY-OprM. Conjugation experiments failed to detect transferable MBL determinants, plasmids were not visualized and bla(VIM) was detected by PCR in the chromosomal band., Conclusions: Multiple carbapenem resistance mechanisms are demonstrated to coexist in a single P. aeruginosa isolate and might confer the high-level carbapenem resistance.

From December 2004 to March 2005, 27 Klebsiella pneumoniae clinical isolates that were positive by the imipenem-EDTA double-disk synergy test and that exhibited a single macro-restriction pattern were recovered in two distinct Greek hospitals. The isolates carried a transferable bla(VIM-1) metallo-beta-lactamase gene in a class 1 integron. Reverse transcriptase PCR showed that the gene was similarly expressed in low- and high-level carbapenem-resistant isolates, indicating the existence of additional resistance mechanisms. The clonal spread of VIM-1-producing K. pneumoniae strains in distinct regions where up to now bla(VIM-2) and bla(VIM-4) alleles were common is worrisome.