Pathogenic characterization of Klebsiella pneumoniae resistant to carbapenems and polymyxin / 中华预防医学杂志

Objective: Analysis and investigation of pathogenic characteristics of polymyxin-and carbapenem-resistant Klebsiella pneumoniae (PR-CRKP). Methods: A total of 23 PR-CRKP strains isolated from clinical specimens from the General Hospital of Southern Theater Command from March 2019 to July 2021 were retrospectively collected, Whole-genome sequencing was performed on 23 PR-CRKP strains, resistance genes were identified by comparison of the CARD and the ResFinder database, high-resolution typing of PR-CRKP strains was analyzed by core genomic multilocus sequencing (cgMLST) and single nucleotide polymorphism (SNP); polymyxin resistance genes were determined by PCR and sequencing. Results: All PR-CRKP strains were KPC-2 producing ST11 types. cgMLST results showed that the evolutionary distance between the PR-CRKP strains and Klebsiella pneumoniae in mainland China was 66.44 on average, which is more closely related than foreign strains; the 23 PR-CRKP strains were divided into 3 main subclusters based on SNP phylogenetic trees, with some aggregation among Clade 2-1 in the isolation department and date. The two-component negative regulatory gene mgrB has seven mutation types including point mutations, different insertion fragments and different insertion positions. Conclusion: The close affinity of PR-CRKP strains indicate the possibility of nosocomial clonal transmission and the need to strengthen surveillance of PR-CRKP strains to prevent epidemic transmission of PR-CRKP.

Clinical distribution and drug resistance characteristics of carbapenem-resistant Klebsiella pneumoniae / 中华预防医学杂志

To explore the clinical distribution and drug resistance characteristics of carbapenem-resistant Klebsiella pneumoniae (CRKP), in order to provide reference for the prevention and treatment of CRKP infection. Retrospective analysis was performed on 510 clinical isolates of CRKP from January 2017 to December 2021, and strain identification and drug sensitivity tests were conducted by MALDI-TOF mass spectrometer and VITEK-2 Compact microbial drug sensitivity analyzer. The carbapenemase phenotype of CRKP strain was detected by carbapenemase inhibitor enhancement test. The CRKP strain was further categorized by immunochromogenic method and polymerase chain reaction (PCR) was used for gene detection. The results showed that 302 strains (59.2%) were derived from sputum, 127 strains (24.9%) from urine and 47 strains (9.2%) from blood. 231 (45.3%) were mainly distributed in intensive care, followed by 108 (21.2%) in respiratory medicine and 79 (15.5%) in neurosurgery. Drug susceptibility test result shows that the resistant rate of tigecycline increased from 1.0% in 2017 to 10.1% in 2021, the difference was statistically significant (χ2=14.444,P<0.05). The results of carbapenemase inhibitor enhancement test showed that 461 carbapenemase strains (90.4%) of 510 CRKP strains, including 450 serinase strains (88.2%), 9 metalloenzyme strains (1.8%), and 2 strains (0.4%) produced both serine and metalloenzyme. 49 strains (9.6%) did not produce enzymes. Further typing by immunochromogenic assay showed that 461 CRKP strains were KPC 450 (97.6%) and IMP 2 (0.4%). 7 NDM (1.5%); 2 strains of KPC+NDM (0.4%); PCR results were as follows: 450 strains of blaKPC (97.6%), 2 strains of blaIMP (0.4%), 7 strains of blaNDM (1.5%), and 2 strains of blaKPC+NDM (0.4%). In conclusion, CRKP strains mainly originated from sputum specimens and distributed in intensive care department, and the drug resistance characteristics were mainly KPC type in carbapenemase production. Clinical microbiology laboratory should strengthen the monitoring of CRKP strains, so as to provide reference for preventing CRKP infection and reducing the production of bacterial drug resistance.

Resistencia a colistina en aislados de Klebsiella pneumoniae resistente a carbapenémicos en un hospital pediátrico de Corrientes / Colistin resistance in carbapenem-resistant Klebsiella pneumoniae isolates from a pediatric hospital from Corrientes, Argentina

INTRODUCCIÓN: Existe un incremento de las infecciones por Klebsiella pneumoniae resistente a carbapenémicos (KPRC) en la población pediátrica y los datos epidemiológicos son limitados. OBJETIVOS: Conocer la frecuencia de KPRC en pacientes pediátricos, determinar la actividad in vitro de colistina y detectar el gen mcr-1 en dichos aislados. MATERIALES Y MÉTODOS: Se estudiaron 220 aislados de K. pneumoniae en un hospital pediátrico durante los años 2018 y 2019. La susceptibilidad antimicrobiana se determinó por microdilución en caldo según CLSI y EUCAST. Los genes blaKPC, blaNDM, blaIMP, blaVIM, blaOXA-48 y mcr-1 se analizaron mediante reacción de polimerasa en cadena (RPC). RESULTADOS: El 9,5% (n: 21) de los aislados fueron caracterizados como KPRC, donde se observó una resistencia a colistina de 47,6% (10/21) con valores de CIM50 de 2 μg/mL y CIM90 de > 4 μg/mL. En todos los aislados de KPRC se caracterizó el gen blaKPC y no se detectó el gen mcr-1. El perfil de resistencia observado en otros antimicrobianos fue el siguiente: gentamicina 100% (n: 21), ciprofloxacina 100% (n: 21), cotrimoxazol 100% (n: 21) y amikacina 19% (n: 4). Se observó 100% de sensibilidad a tigeciclina y ceftazidima/avibactam. CONCLUSIÓN: Este estudio demuestra un valor significativo de la resistencia a colistina en comparación a ceftazidima/avibactam y tigeciclina.

BACKGROUND: There is an increase of carbapenem-resistant Klebsiella pneumoniae (CRKP) infections in the pediatric population and epidemiological data are limited. Aim: To calculate the frequency of CRKP in pediatric patients, to determine the in vitro activity of colistin and to detect the presence of mcr-1 gene in said isolates. METHODS: 220 isolates of K. pneumoniae were studied in a pediatric hospital between January 2018 and December 2019. Antimicrobial susceptibility was determined by microdilution in broth according to guidelines of CLSI and EUCAST. The genes blaKPC, blaNDM, blaIMP, blaVIM, blaOXA-48 and mcr-1 were detected by polymerase chain reaction (PCR). RESULTS: 9.5% (n: 21) of the isolates were characterized as CRKP, where was observed a resistance to colistin of 47.6% (10/21) with values of MIC50 of 2 μg/mL and MIC90 of ≥ 4 μg/mL. In 100% of CRKP strains the blaKPC gene was detected and the mcr-1 gene was not found. The resistance profile to other antimicrobials was as follow: gentamicin 100% (n: 21), trimethoprim/sulfamethoxazole 100% (n: 21), ciprofloxacin 100% (n: 21), amikacin 19% (n: 4). All of the isolates were sensitive to ceftazidime/avibactam and tigecycline. CONCLUSION: This study demonstrates a significant value of resistance to colistin in pediatric patients compared to other last line antimicrobial such as ceftazidime/avibactam and tigecycline.

Riesgo de infección en pacientes oncológicos colonizados por bacterias productoras de p-lactamasas de espectro extendido y enterobacterias productoras de carbapenemasas / Risk of infection in cancer patients colonized by extended expectrum p-lactamases and carbapenem producing Enterobacteriaceae

INTRODUCCIÓN: La prevalencia de microorganismos multirresistentes es un problema de salud pública que continúa creciendo a lo largo del mundo. Existe una población principalmente susceptible de ser colonizada y posteriormente infectarse, son los pacientes oncológicos. OBJETIVO: Identificar las características clínicas y patológicas de los pacientes oncológicos y su relación con la infección con microorganismos productores de BLEE y EPC. PACIENTES Y MÉTODOS: Se condujo un estudio retrospectivo y de carácter analítico entre el primero de enero de 2019 y el 30 de junio de 2020 en tres unidades hemato-oncológicas. RESULTADOS: Incluyó a 3.315 pacientes, de los cuales 217 (6,5%) se encontraban colonizados por microorganismos productores de BLEE y EPC; de éstos, 106/217 (48,8%) presentaron al menos un episodio de infección. El microorganismo más frecuentemente aislado fue Klebsiella pneumoniae, en 29/106 (27,4%). De los infectados, 18/106 (17%) presentaron infección por el mismo microorganismo colonizador. La mucositis (p = 0,002), edad mayor a 65 años (p = 0,041), hipoalbuminemia (p < 0,01), neutropenia (p < 0,01) y la presencia dispositivos invasivos (p < 0,01) demostraron una relación con el desarrollo de infección. CONCLUSIÓN: La presencia de hipoalbuminemia (OR 3,3, IC 1,5-7,1, p < 0,01), dispositivos invasivos (OR 5,8, IC 3.0-11,4, p < 0,01) y neutropenia (OR 4,1, IC 1,5-11,4, p < 0,01) predicen el desarrollo de infecciones.

BACKGROUND: The prevalence of multi-resistant microorganisms is a public health problem that continues to grow globally. There is a population that is mainly susceptible to being colonized and subsequently infected, and these are cancer patients. AIM: To identify the clinical and pathological characteristics of cancer patients and their relationship with infection with ESBL and CPE producing microorganisms. METHODS: A retrospective and analytical study was conducted between January 1, 2019 and June 30, 2020 in three hematooncological units. RESULTS: We included 3315 patients of which 217 (6.5%) were colonized by microorganisms producing ESBL and CPE. Of these, 106/217 (48.8%) had at least one episode of infection. The most frequently isolated microorganism was Klebsiella pneumoniae 29/106 (27.4%). Of those infected, 18/106 (17%) presented infection by the same colonizing microorganism. Mucositis (p = 0.002), age over 65 years (p = 0.041), hypoalbuminemia (p < 0.01), neutropenia (p < 0.01) and the presence of invasive devices (p < 0.01) demonstrated a relationship with development of infection. The presence of hypoalbuminemia (OR 3.3, CI 1.5-7.1, P < 0.01), invasive devices (OR 5.8, CI 3.0-11.4, p < 0.01) and neutropenia (OR 4.1, CI 1.5-11.4, p < 0.01) predict the development of infections.

Analysis of molecular and clinical characteristics of carbapenem-resistant hypervirulent Klebsiella pneumoniae in the intensive care unit / 中华预防医学杂志

To investigate the carbapenemases distribution of carbapenem-resistant Klebsiella pneumoniae (CRKP) in the intensive care unit, and the clinical characteristics between carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP) and carbapenem-resistant non-hypervirulent Klebsiella pneumoniae (CR-non-hvKP) were compared. A total of 53 non-repetitive CRKP strains isolated from 49 patients in the intensive care unit of the Second Affiliated Hospital of Xi'an Jiaotong University from May 2020 to March 2021 were retrospectively studied. The carbapenemase inhibitor enhancement test was used for screening carbapenemase-producing strains, and the string test was carried out to screen the hypermucoviscosity phenotype. Using PCR to detect five main carbapenemase genes (blaKPC-2, blaNDM, blaIMP , blaVIM and blaOXA-48-like), common serotype (K1 and K2) and virulence gene (rmpA and iutA). Treated the strains with both rmpA and iutA genes as hypervirulent Klebsiella pneumonia (hvKP), and the whole genome sequencing of CR-hvKP was completed. At the same time, the clinical data of 49 patients were sorted out, and the differences in clinical characteristics of CR-hvKP and CR-non-hvKP infected patients were compared using the independent sample t test, Mann-Whitney U test, chi-square test or Fisher's exact probability test. CRKP isolated from the intensive care unit were extensively drug resistance and still had a good sensitivity to polymyxin B and tigecycline. Producing carbapenemases were the main resistance mechanism of CRKP (52/53, 98.1%). Of the 53 CRKP strains, except for 1strain that did not detect carbapenemase, at least one carbapenemase resistance gene was detected in the remaining 52 CRKP strains, of which 45 strains carried an enzyme, including 36 blaKPC-2 (36/53, 67.9%), 8 blaNDM (8/53, 15.1%), 1 blaIMP (1/53, 1.9%), and 7 strains carried with both blaKPC-2 and blaNDM (7/53, 13.2%). String test and virulence gene showed that 7 CR-hvKP strains (13.2%) were detected in 53 CRKP strains, and two of which were hypermucoviscosity phenotype. Sequencing results revealed that CR-hvKP were mainly ST11 type. Almost all patients with CR-hvKP infection were over 60 years old (7/7), with invasive treatment (7/7), pulmonary infection with hypermucoviscosity phenotype (2/7) and high mortality (5/7); and the percentage of neutrophils in patients with CR-hvKP infection (86.44±4.70) % was higher than those patients with CR-non-hvKP infection (78.90±19.15) %, the difference was statistically significant (t=-2.225, P=0.032). The CR-hvKP strains in the intensive care unit mainly produced KPC-2 enzyme, with K2 capsular serotype and ST11 type. It is necessary to strengthen the monitoring and control of the CR-hvKP strain to prevent the co-evolution of drug-resistant and hypervirulent strains.

Risk factors for the colonization or infection of carbapenem-resistant Enterobacteriaceae in children: a Meta analysis / 中国当代儿科杂志

OBJECTIVES@#To systematically assess the risk factors for the colonization or infection of carbapenem-resistant Enterobacteriaceae in children.@*METHODS@#PubMed, Web of Science, China National Knowledge Infrastructure Database, Wanfang Data, China Biology Medicine disc were searched to obtain the articles on risk factors for the colonization or infection of carbapenem-resistant Enterobacteriaceae in children published up to May 31, 2021. RevMan 5.3 software was used to perform the Meta analysis.@*RESULTS@#A total of 13 articles were included, with 1 501 samples in total. The Meta analysis showed that indwelling gastric tube (OR=4.91), tracheal intubation (OR=5.03), central venous catheterization (OR=3.75), indwelling urinary catheterization (OR=4.11), mechanical ventilation (OR=3.09), history of hospitalization in the intensive care unit (OR=2.39), history of surgical operation (OR=3.22), previous use of third-generation cephalosporins (OR=2.62), previous use of carbapenem antibiotics (OR=3.82), previous use of glycopeptide antibiotics (OR=3.48), previous use of β-lactamase inhibitors (OR=2.87), previous use of antifungal drugs (OR=2.48), previous use of aminoglycoside antibiotics (OR=2.54), and Apgar score ≤7 at 1 minute after birth (OR=2.10) were risk factors for the colonization or infection of carbapenem-resistant Enterobacteriaceae in children (P<0.05).@*CONCLUSIONS@#Invasive operations, history of hospitalization in the intensive care unit, previous use of antibiotics such as carbapenem antibiotics, and Apgar score ≤7 at 1 minute after birth are risk factors for the colonization or infection of carbapenem-resistant Enterobacteriaceae in children.

Tipos de carbapenemasas expresadas en Klebsiella spp, y Pseudomonas aeruginosa resistente a carbapenémicos en seis hospitales de alta complejidad de la Ciudad de Bogotá - Colombia / Carbapenemases produced in Klebsiella spp, and Pseudomonas aeruginosa in six hospitals in Bogotá - Colombia

INTRODUCCIÓN: En las últimas décadas, se ha incrementado la prevalencia de infecciones por bacilos gramnegativos resistentes a carbapenémicos. OBJETIVO: Determinar los tipos y la frecuencia de las distintas carbapenemasas en aislados de Klebsiella spp. y Pseudomonas aeruginosa, en seis hospitales de alta complejidad de Bogotá-Colombia. MÉTODOS: Estudio observacional descriptivo en seis hospitales de la ciudad de Bogotá, en el período de enero de 2017 a agosto de 2018. Se realizaron RPC para genes de KPC, GES, VIM, NDM, IMP y OXA-48 en cepas de Klebsiella spp y P aeruginosa resistentes a carbapenémicos. RESULTADOS: 52 aislados de P aeruginosa amplificaron para una carbapenemasa, de los cuales 39 (75%) fueron positivos para KPC, 11 (21%) para VIM y 2 co-producciones de KPC y VIM. En cuanto a Klebsiella spp., 165 cepas amplificaron al menos para una carbapenemasa, 98% expresaron KPC y 4 aislados tuvieron co-producciones de metalo-beta-lactamasas y KPC. DISCUSIÓN: Este estudio aporta información valiosa, como el incremento de producción de KPC en P. aeruginosa y la co-producción de KPC y metalo-beta-lactamasas, locual tiene una implicancia tanto en la selección del tratamiento, las medidas de aislamiento de contacto y el pronóstico de los pacientes.

BACKGROUND: In the last decades, the prevalence of infections by carbapenem resistant gram-negative bacilli has been increased. OBJECTIVE: To determine types and frequency of the different carbapenemases in Klebsiella spp. and Pseudomonas aeruginosa, in six hospitals in Bogotá-Colombia. METHODS: Descriptive and observational study, in six hospitals in the city of Bogotá, in the period ftom January 2017 to August 2018. PCR were performed for KPC, GES, VIM, NDM, IMP and OXA-48 genes, in carbapenem resistant Klebsiella spp. and P aeruginosa. RESULTS: 52 P aeruginosa isolates amplified a carbapenemase gene, of which 39 (75%) were positive for KPC, 11 (21%) for VIM and two co-productions of KPC and VIM. Regarding Klebsiella spp. 165 strains amplified at least one carbapenemase gene, 98% expressed KPC and four isolates had co-productions of metallo-P-lactamases and KPC. DISCUSSION: This study provides valuable information, such as the increased production of KPC in P. aeruginosa información valiosa, como el incremento de producción de KPC en P. aeruginosa and the co-production of KPC plus metallobetalactamases, which has an implication both in treatment selection, isolation precautions and patient prognosisy.

Carbapenemasas en aislamientos de Pseudomonas aeruginosa resistentes a carbapenémicos aisladas en hospitales de Chile

Resumen Introducción: La resistencia a carbapenémicos mediada por carbapenemasas en Pseudomonas aeruginosa es un mecanismo importante; sin embargo, la pérdida de la porina OprD continúa siendo el mecanismo más frecuente. Objetivo: Determinar la proporción de aislados de P. aeruginosa, resistentes a imipenem y/o meropenem, productores de carbapenemasas, el tipo de enzima producida y la relación genética entre los aislados. Material y Métodos: Se incluyó 113 aislados resistentes al menos a un carbapenémico, provenientes de 12 hospitales de 9 ciudades de Chile. Adicionalmente se determinó la susceptibilidad a ceftazidima, amikacina, gentamicina, piperacilina/tazobactam, ciprofloxacina y colistina. Se realizó Carba NP y en los aislados positivos (n: 61) se detectó genes de carbapenemasas por RPC. Los aislados fueron tipificados por restricción con SpeI y PFGE. Resultados: No todos los aislados presentan carbapenemasas, y sólo en 61/113 de ellos (54%) se amplificó blaKPC (32) o blaVIM (29). En ninguno de los aislados se encontró co-portación de ambos genes. Los pulsotipos indican que no hay diseminación clonal de los aislados, evidenciando una importante diversidad genética. Conclusiones: Los aislados de P. aeruginosa productores de carbapenemasas, obtenidos en hospitales de Chile, portan genes blaKPC y blaVIM y, en su mayoría, son policlonales. Estos resultados ponen énfasis en la importancia de realizar estudios epidemiológicos con mayor número de aislados que permitan conocer mejor la epidemiología de P. aeruginosa productoras de carbapenemasas en Chile.

Abstract Background: Carbapenem resistance mediated by carbapenemases in Pseudomonas aeruginosa is an important mechanism; however, loss of porin OprD remains as the most frequent. Aim: To determine the proportion of P. aeruginosa isolates, resistant to imipenem and/or meropenem, producing carbapenemases, the type of enzyme produced and the genetic relationship between the isolates. Methods: One hundred and thirteen resistant to at least one carbapenem isolates, obtained in 12 hospitals and 9 cities in Chile were studied. Additionally, susceptibility to ceftazidime, amikacin, gentamicin, piperacillin/tazobactam, ciprofloxacin and colistin was determined. Carba NP was performed and in the positive isolates carbapenemase genes were detected by PCR. The isolates were typified by restriction with SpeI and PFGE. Results: Not all isolates produce carbapenemases, and only in 61/113 of them (54%) the blaKPC (32) or blaVIM (29) was amplified. In none of the isolates was found the coharboring of both genes. The pulsotypes indicated no clonal dissemination of the isolates, evidencing an important genetic diversity. Conclusions: P. aeruginosa isolates producing carbapenemases, obtained in Chilean hospitals carry blaKPC and blaVIM genes and, mostly, are polyclonal. These results emphasize the importance of carrying out epidemiological studies with a greater number of isolates to allow a better understanding of the epidemiology of carbapenemase-producing P. aeruginosa in Chile.

What Are the Roles of Carbapenems in an Institution-specific Epidemiological Antibiogram in East Trinidad?

ABSTRACT Objective: To provide an overview of the development of an institution-specific epidemiological antibiogram. Emphasis was on last-line antibiotics, such as carbapenems. Methods: In 2013, the antibiograms of various organisms were retrieved from the computerized database of the Microscan (Siemens Healthcare) at the Microbiology Laboratory of the Sangre Grande Hospital in East Trinidad, West Indies. These were divided into blood and urine specimen antibiograms. All the wards and hospital clinics were included. A 20% cut-off was used to determine that a particular antibiotic or antibiotic class could be used for empiric therapy. All the organisms were not chosen. Only the most common and clinically relevant organisms were chosen. Results: Blood: Escherichia coli, Klebsiella pneumonia, Proteus mirabilis: Imipenem, mero- penem, ertapenem showed greater than 80% sensitivity, respectively. Pseudomonas aeruginosa: ceftazidime, ciprofloxacin, gentamicin, levofloxacin and tazobactam/piperacillin showed 100%, 80%, 80%, 100% and 100% sensitivity, respectively. Urines: E. coli, Klebsiella pneumonia, Proteus mirabilis: Imipenem, meropenem, ertapenem, were greater than 80% sensitive. Enterobacter cloacae: Imipenem, meropenem were 92%, 100% sensitive. Pseudomonas aeruginosa: tazobactam-piperacillin and amikacin were both 85% susceptible. Acinetobacter baumanii/haemolyticus: All the antibiotics were above the 20% resistance threshold. Conclusion: Patient-specific antibiograms and unit-specific trends (eg, ICU, surgical wards and outpatient clinic) can be used as a guide in patients with less severe infections. Carbapenems can still be used empirically, in East Trinidad, for sepsis.

Active surveillance of carbapenem-resistant Gram-negative healthcare-associated infections in a low-middle-income country city

ABSTRACT Background: Carbapenem-resistance in healthcare-associated infections (HCAIs) is of great concern, and it is urgent to improve surveillance. We aimed to describe and analyze HCAIs trends on Gram-negative antimicrobial susceptibility in a city from a developing country, following the implementation of an active surveillance program. Methods: This is an aggregated study describing data from 24 hospitals with intensive care units, including a trend analysis by Joinpoint regression between January 2012 and December 2017. Results: There were 23,578 pathogens in 39,832 HCAIs, from which 16,225 were Gram-negatives (68.8%). Carbapenem susceptibility was lowest in A. baumannii (15.4-25.9%), K. pneumoniae (51.0-55.9%), and P. aeruginosa (64.9-84.1%) and highest in E. coli (96.5-99.2%). Only K. pneumoniae showed a significant Joinpoint at 95% confidence interval: −10.71% (−18.02; −2.75) from 2012 to 2014, p = 0.02, and 6.54% (−2.00; 15.83) from 2015 to 2017, p = 0.12, which was most influenced by urinary tract infections: −9.98% (−16.02; −3.48) from 2012 to 2014, p = 0.01, and 9.66% (−1.75; 22.39) from 2015 to 2017, p = 0.09. Conclusion: Although we found a significant change toward an improvement in carbapenem susceptibility in K. pneumoniae, resistance is high for most pathogens. These data should encourage health institutions to improve their prevention and control strategies.

Caracterización clínica, epidemiológica y microbiológica de bacteriemias producidas por enterobacterias resistentes a carbapenems en un hospital universitario de Córdoba, Argentina / Clinical, epidemiological and microbiological characterization of bacteremia produced by carbapenem-resistant enterobacteria in a university hospital in Córdoba, Argentina

Resumen Introducción: Las enterobacterias son una causa principal de infecciones del torrente sanguíneo y su resistencia antimicrobiana se encuentra en aumento. Esto lleva a un incremento de la morbilidad-mortalidad y de los costos en la salud pública. Las enterobacterias resistentes a carbapenems representan un grave desafío a nivel global ya que existen escasas opciones terapéuticas disponibles. Objetivo: Caracterización clínico/microbiológica de las bacteriemias resistentes a carbapenémicos observadas en un período de 4 años. Material y Método: Estudio retrospectivo, observacional y descriptivo, sobre las bacteriemias por enterobacterias resistentes y sensibles a carbapenems. Resultados: Se analizó un total de 84 pacientes con bacteriemia por enterobacterias resistentes y sensibles a carbapenems. Entre las resistentes, observamos una mayor proporción de: tratamiento antimicrobiano previo, hospitalización en unidad de terapia intensiva (UTI), inicio de la bacteriemia en UTI y antecedentes de β-lactamasas de espectro extendido. Además, se detectó un amplio predominio de Klebsiella pneumoniae productor de KPC y una mortalidad atribuible de 52,4%. Discusión: El estudio posibilitó profundizar el conocimiento de una enfermedad emergente de elevada mortalidad, en vistas al diseño y aplicación de estrategias de control de infecciones y de esquemas de tratamiento efectivos adaptados a la epidemiologia local.

Abstract Background: Enterobacteriaceae are a major cause of bloodstream infections and their antimicrobial resistance continues to increase. This leads to higher morbidity-mortality rates and public health costs. Carbapenem-resistant Enterobacteriaceae represent a serious challenge globally, since there are few therapeutic options available. Aim: Clinical/microbiological characterization of the carbapenem-resistant bacteremia observed over a period of 4 years. Methods: Retrospective, observational and descriptive study about bacteremia caused by carbapenem-resistant and susceptible Enterobacteriaceae. Results: A total of 84 patients with bacteremia including carbapenem-resistant and susceptible Enterobacteriaceae were analyzed. We found that patients infected with carbapenem-resistant strains presented a higher proportion of: previous antibiotic treatment, hospitalization in intensive care unit (ICU), onset of the bacteremia during hospitalization in ICU and previous infection with extended-spectrum-beta-lactamase producing Enterobacteriaceae. Additionally, we observed a predominance of KPC-producing Klebsiella pneumoniae and an attributable mortality rate of 52.4%. Discussion: This study allowed for a better understanding of an emerging problem with high mortality, which in turn is useful for the design and adoption of infection control strategies and effective treatment regimens adapted to our local epidemiology.

Carbapenemasas en Pseudomonas aeruginosa con susceptibilidad disminuida a los carbapenémicos después de una década, desde VIM a KPC / Carbapenemases in Pseudomonas aeruginosa with decreased susceptibility to carbapenems after a decade: from VIM to KPC

Resumen Introducción: Pseudomonas aeruginosa es relevante en infecciones asociadas a la atención de salud, principalmente cuando presenta resistencia a carbapenémicos. Objetivos: Estudiar la producción de carbapenemasas en P. aeruginosa, con susceptibilidad disminuida a carbapenémicos procesadas en el Laboratorio de Microbiología de la Red de Salud UC-CHRISTUS entre 2014-2015, y compararlas con las cepas estudiadas en 2004-2005. Métodos: Entre enero de 2014 y junio de 2015, se aislaron 459 cepas de P. aeruginosa provenientes de muestras clínicas. La susceptibilidad fue determinada por dilución en agar y a las cepas con susceptibilidad disminuida a carbapenémicos se les realizó test de carbaNP. Las cepas positivas fueron estudiadas por RPC para genes blaVIM, blaVIM-1, blaVIM-2, blaIMP, blaNDM, blaKPC, blaOXA y blaIMI. Se realizó en cepas seleccionadas electroforesis de campo pulsado. Resultados: De las 459 cepas estudiadas, 300 presentaban susceptibilidad disminuida a carbapenémicos (65,3%). De éstas, 183 fueron viables para estudio, correspondientes a 164 pacientes. El test de carbaNP fue positivo en 44 cepas de las 183 cepas (24%). Los genes de resistencia encontrados fueron: blaVIM-2 en 35 cepas, blaKPC-2+VIM-2 en 7 cepas y blaKPC-2 en 2 cepas. En las cepas blaKPC-2 se encontró relación clonal entre ellas. Conclusiones: Un 65,3% de P. aeruginosa presentó susceptibilidad disminuida a carbapenémicos, observándose que la presencia de carbapenemasas no es el principal mecanismo de resistencia. Además, se describe la emergencia en Chile de cepas de P. aeruginosa con carbapenemasas del tipo KPC-2 sola o en combinación con VIM-2.

Abstract Background: Pseudomonas aeruginosa is a relevant infectious agent affecting patients within health care setting; this situation is worsening with the appearance of strains resistance to carbapenems. Aims: To study carbapenemase production in P. aeruginosa with decreased susceptibility to carbapenems processed in the microbiology laboratory of the Health Network UC-CHRISTUS in 2014-2015 and compare them with the strains studied in 2004-2005. Methods: Between January 2014 and June 2015, 459 strains of P. aeruginosa from clinical samples were isolated. Susceptibility was determined by dilution in agar and strains with reduced susceptibility to carbapenems were tested for carbaNP. Positive strains were studied by PCR for blaVIM, blaVIM-1, blaVIM-2, blaIMP, blaNDM, blaKPC, blaOXA and blaIMI genes. Pulsed field electrophoresis was performed on selected strains. Results: From 459 strains studied, 300 had reduced susceptibility to carbapenems (65.3%). Of these, 183 were viable for study, corresponding to 164 patients. The carbaNP test was positive in 44 strains of the 183 strains (24%). The resistance genes found were: blaVIM-2 in 35 strains, blaKPC-2+VIM-2 in 7 strains and blaKPC-2 in 2 strains. In the blaKPC-2 strains clonal relation between them was found. Conclusions: A 65.3% of P. aeruginosa presented decreased susceptibility to carbapenems being the presence of carbapenemases not the main resistance mechanism. In addition, the emergence in Chile of P. aeruginosa strains with bla of the KPC-2 type alone or in combination with VIM-2 is described.

Carbapenem stewardship with ertapenem and antimicrobial resistance-a scoping review

Abstract Consumption of carbapenem has increased due to extended-spectrum beta-lactamase-producing bacteria spreading. Ertapenem has been suggested as a not carbapenem-resistance inducer. We performed a scoping review of carbapenem-sparing stewardship with ertapenem and its impact on the antibiotic resistance of Gram-negative bacilli. We searched PubMed for studies that used ertapenem as a strategy to reduce resistance to carbapenems and included epidemiologic studies with this strategy to evaluate susceptibility patterns to cephalosporins, quinolones, and carbapenems in Gram-negative-bacilli. The search period included only studies in English, up to February 2018. From 1294 articles, 12 studies were included, mostly from the Americas. Enterobacteriaceae resistance to quinolones and cephalosporins was evaluated in 6 studies and carbapenem resistance in 4 studies. Group 2 carbapenem (imipenem/meropenem/doripenem) resistance on A. baumannii was evaluated in 6 studies. All studies evaluated P. aeruginosa resistance to Group 2 carbapenem. Resistance profiles of Enterobacteriaceae and P. aeruginosa to Group 2 carbapenems were not associated with ertapenem consumption. The resistance rate of A. baumannii to Group 2 carbapenems after ertapenem introduction was not clear due to a lack of studies without bias. In summary, ertapenem as a strategy to spare use of Group 2 carbapenems may be an option to stewardship programs without increasing resistance of Enterobacteriaceae and P. aeruginosa. More studies are needed to evaluate the influence of ertapenem on A. baumannii.

Epidemiología molecular de aislados de Acinetobacter baumannii resistentes a carbapenems en Argentina / Molecular epidemiology of carbapenem-resistant isolates of Acinetobacter baumannii in Argentina

Se estudiaron 100 aislados consecutivos y no epidemiológicamente relacionados de Acinetobacter baumannii resistentes a los carbapenems, recuperados entre enero y agosto de 2016 de muestras clínicas en 11 hospitales de 10 provincias de la Argentina, ubicadas en distintas regiones del país. Los genes que codifican las carbapenemasas de Ambler clase D y clase B se investigaron mediante la técnica de PCR utilizando cebadores específicos. Todos los aislados se agruparon mediante las técnicas de 3-locus sequence typing y la secuenciación del gen blaOXA-51-like. El gen blaOXA-23 se recuperó en todos los aislados estudiados. La población de A. baumannii resistente a carbapenems en Argentina estuvo asociada, principalmente, con ST1 (45%), ST25 (34%) y ST79 (15%). ST25 se recuperó en todas las regiones estudiadas y no se detectó CC2.

One hundred sequential, epidemiologically unrelated carbapenem-resistant- Acinetobacter baumannii isolates from 11 hospitals in 10 Argentine provinces were collected between January and August 2016. Genes coding for Ambler class D and B carbapenemases were investigated by PCR using specific primers. All isolates were typed using the 3-locus sequence typing and b/aOXA-51-like sequence-based typing techniques. The blaOXA-23 gene was recovered in all isolates studied. The population of carbapenem-resistant- A. baumannii in Argentina was principally associated with ST1 (45%), ST25 (34%) and ST79 (15%). ST25 was recovered in all the regions studied and CC2 was not detected.

Costos médicos directos de las infecciones del tracto urinario por bacilos Gram negativos resistentes a betalactámicos en un hospital de alta complejidad de Medellín, Colombia / Direct medical costs of urinary tract infections by Gram-negative bacilli resistant to beta-lactams in a tertiary care hospital in Medellín, Colombia

Resumen Introducción. Las infecciones del tracto urinario son muy frecuentes en el ámbito hospitalario. Debido a la aparición de la resistencia antimicrobiana, la complejidad de los procesos de atención ha aumentado y, con ello, la demanda de recursos. Objetivo. Describir y comparar el exceso de los costos médicos directos de las infecciones del tracto urinario por Klebsiella pneumoniae, Enterobacter cloacae y Pseudomonas aeruginosa resistentes a betalactámicos. Materiales y métodos. Se llevó a cabo un estudio de cohorte en una institución de tercer nivel de Medellín, Colombia, entre octubre del 2014 y septiembre del 2015. Se incluyeron los pacientes con infección urinaria, unos por bacterias sensibles a los antibióticos betalactámicos, y otros por bacterias resistentes a las cefalosporinas de tercera y cuarta generación y a los antibióticos carbapenémicos. Los costos se analizaron desde la perspectiva del sistema de salud. La información clínico-epidemiológica se obtuvo de las historias clínicas y los costos se calcularon utilizando los manuales tarifarios estándar. El exceso de costos se estimó mediante análisis multivariados. Resultados. Se incluyeron 141 pacientes con infección urinaria: 55 (39 %) por bacterias sensibles a los betalactámicos, 54 (38,3 %) por bacterias resistentes a las cefalosporinas y 32 (22,7 %) por bacterias resistentes a los carbapenémicos. El exceso de costos totales ajustado de los 86 pacientes con infecciones del tracto urinario por bacterias resistentes a las cefalosporinas y a los carbapenémicos, fue de USD$ 193 (IC95% -347 a 734) y USD$ 633 (IC95% -50 a 1.316), respectivamente comparados con el grupo de 55 pacientes por bacterias sensibles a los betalactámicos. Las diferencias se presentaron principalmente en el uso de antibióticos de amplio espectro, como el meropenem, la colistina y la fosfomicina. Conclusión. Los resultados evidenciaron un incremento sustancial de los costos médicos directos de los pacientes con infecciones del tracto urinario por bacterias resistentes a las cefalosporinas o a los carbapenémicos. Esta situación genera especial preocupación en los países endémicos como Colombia, donde la alta frecuencia de infecciones del tracto urinario y de resistencia a los betalactámicos puede causar un mayor impacto económico en el sector de la salud.

Abstract Introduction: Urinary tract infections are very frequent in the hospital environment and given the emergence of antimicrobial resistance, they have made care processes more complex and have placed additional pressure on available healthcare resources. Objective: To describe and compare excess direct medical costs of urinary tract infections due to Klebsiella pneumoniae, Enterobacter cloacae and Pseudomonas aeruginosa resistant to beta-lactams. Materials and methods: A cohort study was conducted in a third level hospital in Medellín, Colombia, from October, 2014, to September, 2015. It included patients with urinary tract infections caused by beta-lactam-susceptible bacteria, third and fourth generation cephalosporin-resistant, as well as carbapenem-resistant. Costs were analyzed from the perspective of the health system. Clinical-epidemiological information was obtained from medical records and the costs were calculated using standard tariff manuals. Excess costs were estimated with multivariate analyses. Results: We included 141 patients: 55 (39%) were sensitive to beta-lactams, 54 (38.3%) were resistant to cephalosporins and 32 (22.7%) to carbapenems. The excess total adjusted costs of patients with urinary tract infections due to cephalosporin- and carbapenem-resistant bacteria were US$ 193 (95% confidence interval (CI): US$ -347-734) and US$ 633 (95% CI: US$ -50-1316), respectively, compared to the group of patients with beta-lactam sensitive urinary tract infections. The differences were mainly found in the use of broad-spectrum antibiotics such as meropenem, colistin, and fosfomycin. Conclusion: Our results show a substantial increase in the direct medical costs of patients with urinary tract infections caused by beta-lactam-resistant Gram-negative bacilli (cephalosporins and carbapenems). This situation is of particular concern in endemic countries such as Colombia, where the high frequencies of urinary tract infections and the resistance to beta-lactam antibiotics can generate a greater economic impact on the health sector.

Carbapenemases novas ou emergentes em Pseudomonas aeruginosa / New or emerging carbapenemases in Pseudomonas aeruginosa

Pseudomonas aeruginosa é um importante agente de infecções relacionadas à assistência à saúde em todo o mundo. O tratamento empírico de infecções graves causadas por esta espécie usualmente inclui os carbapenêmicos. Essa terapia, se inadequada, está relacionada a um aumento significativo da mortalidade. Os principais mecanismos de resistência aos carbapenêmicos em bacilos Gram-negativos são a redução da permeabilidade da membrana externa, hiperexpressão de bombas de efluxo e produção de betalactamases, sendo este último, o mais eficiente. O objetivo deste trabalho consistiu na caracterização de carbapenemases novas ou emergentes e seu contexto genético em P. aeruginosa. Foram utilizados 11 isolados de P. aeruginosa capazes de hidrolisar o imipenem em ensaio espectrofotométrico e negativos para genes de carbapenemases conhecidos e uma cepa produtora de KPC-2. Tais isolados foram submetidos à confirmação do perfil de resistência aos carbapenêmicos pelos métodos de disco-difusão e microdiluição em caldo (CIM), bloqueio enzimático com EDTA e Blue-Carba. O perfil plasmidial foi avaliado utilizando-se os métodos de lise alcalina e eletroforese em campos pulsados (PFGE). Os genomas foram sequenciados utilizando-se o sistema MiSeq. O perfil clonal dos isolados foi avaliado por PFGE e Multilocus Sequence Typing (MLST). Dez isolados apresentaram Blue-Carba negativo, compatível com a presença de carbapenemases fracas. Quatro isolados apresentaram plasmídeos, visualizados em gel de agarose após PFGE. Os plasmídeos do isolado D5303023 foram eletroporados em E. coli TOP 10 e selecionados em meio LB contendo 1µg/mL imipenem, contudo não foram obtidos transformantes. A análise por PFGE identificou sete grupos clonais distintos. Quanto à tipagem por MLST, foi detectado um novo tipo ST3187 e os ST277 e ST1560 foram os predominantes. O isolado D9203039 apresentou uma carbapenemase GES-20 associada a uma betalactamase de espectro estendido GES-19, sendo os genes que as codificam localizados no integron In724. Esse isolado pertence ao ST309, clone de potencial alto risco, associado ao fenótipo de resistência a múltiplos antimicrobianos no México. O genoma da cepa positiva para KPC-2 foi digerido com a S1 nuclease e submetido à PFGE, evidenciando um plasmídeo de aproximadamente 453 kb. Após análise do sequenciamento confirmou-se que a cepa pertence ao ST446 e foi observada a presença do gene blaKPC-2 em um contig de 128.487 bp. Este contig apresentou 99,9% de similaridade com o plasmídeo 1 da cepa P. aeruginosa RW109; no entanto, ensaios de conjugação bacteriana falharam em obter colônias de transconjugantes. O gene blaKPC-2 foi encontrado flanqueado à montante por uma estrutura truncada de um transpóson da família Tn3 e à jusante por uma ISKpn6 truncada. As análises das sequências de DNA das demais cepas evidenciaram a presença de sequências gênicas, que traduzidas, apresentavam similaridade para sete metalobetalactamases (MBL), indicando a potencial presença de novos genes de carbapenemases. Foi caracterizada pela primeira vez no Brasil cepa produtora da carbapenemase GES-20 e o novo ST3187. Foram detectados potenciais novos genes de carbapenemases. O gene blaKPC-2 no isolado J5083553 tem provável localização plasmidial

Pseudomonas aeruginosa is a major agent of healthcare-related infections worldwide. Empirical treatment of serious infections caused by this species usually includes carbapenems. This therapy, if inadequate, is related to a significant increase in mortality. The main mechanisms of carbapenem resistance in Gram-negative bacteria are the reduction of outer membrane permeability, overexpression of efflux pumps and beta-lactamase production, the latter being the most efficient. The aim of this work was the characterization of new or emerging carbapenemases and their genetic context in P. aeruginosa. Eleven P. aeruginosa isolates capable of hydrolyzing imipenem in spectrophotometric assay and negative for known carbapenemases genes were used, as well as a KPC-2 producing strain. These isolates were subjected to confirmation of carbapenem resistance profile by disk diffusion, broth microdilution (MIC) and enzyme inhibition by EDTA and Blue-Carba methods. Plasmid profile was evaluated using alkaline lysis and pulsed field electrophoresis (PFGE) methods. Genomes were sequenced using the MiSeq system. The clonal profile of the isolates was evaluated by PFGE and Multilocus Sequence Typing (MLST). Ten isolates presented negative Blue-Carba, compatible with the presence of weak carbapenemases. Four isolates presented plasmids visualized on agarose gel after PFGE. The plasmids of isolate D5303023 were electroporated into E. coli TOP 10 and selected in LB medium containing 1 µg/mL imipenem, however no transformants were obtained. The PFGE analysis identified 7 distinct clonal groups. As for MLST typing, a new type ST3187 was detected and the ST277 and ST1560 were the predominant types. The genome of the KPC-2 positive strain was digested with S1 nuclease and subjected to PFGE, evidencing a plasmid of approximately 453 kb. Isolate D9203039 presented a GES-20 carbapenemase associated with a GES-19 extended spectrum beta-lactamase. The genes encoding them were located in the In724 integron. This isolate belonged to ST309, a potential high risk clone, associated with the multidrug resistant strain in Mexico. After sequencing it was confirmed that the strain belongs to ST446 and it was observed the presence of the blaKPC-2 gene in a contig of 128,487 bp. This contig was 99.9% similar to plasmid 1 of the P. aeruginosa RW103 strain. However, bacterial conjugation assays failed to obtain transconjugant colonies. The blaKPC-2 gene was found flanked upstream by a truncated structure of a Tn3 family transposon and downstream by a truncated ISKpn6. DNA sequence analysis of the other strains showed the presence of gene sequences, which translated, showed similarity to seven metallo-beta-lactamases (MBL), indicating the potential presence of new carbapenemase genes. It was characterized for the first time in Brazil carbapenemase producing strain GES-20 and the new ST3187. Potential new carbapenemase genes were detected. The blaKPC-2 gene in isolate J5083553 has plasmid localization

Origanum vulgare L. essential oil inhibits the growth of carbapenem-resistant gram-negative bacteria

Abstract INTRODUCTION: Plant products are sources for drug development against multidrug resistant bacteria. METHODS The antimicrobial activity of Origanum vulgare L. essential oil (OVeo) against carbapenem-resistant strains was assessed by disk-diffusion, microdilution (REMA-Resazurin Microtiter Assay), and time kill assays. RESULTS Carbapenemase production was confirmed for all strains. OVeo exhibited a minimum inhibitory concentration of 0.059% v/v for Klebsiella pneumoniae and Serratia marcescens, and of 0.015 % v/v for Acinetobacter baumannii. A decrease in cell count was observed after a 4 h treatment. CONCLUSIONS OVeo antimicrobial effect was rapid and consistent, making it a candidate for developing alternative therapeutic options against carbapenem-resistant strains.

Bacteriemia por Pseudomonas aeruginosa (PAE) en niños / Pseudomonas aeruginosa-associated bacteremia en children

Introducción. La bacteriemia por Pseudomonas aeruginosa (PAE) en niños es infrecuente. Objetivo.Describir las características epidemiológicas, clínicas, microbiológicas y evolutivas en niños con bacteriemia por PAE. Métodos. Estudio de cohorte retrospectivo. Resultados. Se incluyeron 100 pacientes (p). La mediana de edad fue de 27 meses (RIC 6-88).Tenían enfermedad de base: 93 p (93%) y 36 de ellos estaban neutropénicos. Ochenta y cinco p (85%) habían recibido antibióticos en el último mes, 60 (60%) tuvieron procedimientos invasivos previos y 81 (81%) tuvieron internaciones previas. Ingresaron con shock séptico 42 p (42%), 56 p (56%) fueron admitidos en unidad de cuidados intensivos (UCI) y 49 (49%) requirieron ventilación mecánica (VM). La bacteriemia fue primaria en 17 p (17%); asociada a catéter en 15 p (15%) y secundaria en 68 p (68%). El foco más frecuente fue mucocutáneo, 21 p, seguido por el pulmonar, 20 p. El tratamiento empírico fue adecuado en 84 p (84%). La resistencia a uno o más grupos de antibióticos se dio en el 38% de los casos, 11% fueron multirresistentes y 15% fueron resistentes sólo a carbapenemes. Fallecieron 31 p (31%). Pseudomonas aeruginosa resistente a carbapenemes en forma exclusiva o combinada con otros antibióticos se relacionó en esta serie a exposición previa a antibióticos, (p≤0,03), tratamiento empírico inicial inadecuado (p≤0,006) y mayor mortalidad (p≤0,01), prolongación de la internación y del tiempo de tratamiento (p≤0,001)

Introduction. Pseudomonas aeruginosa (PAE) associated bacteremia is uncommon in children. Objective. To describe the epidemiological, clinical, and microbiological features and outcome in children with PAE-associated bacteremia. Methods. A retrospective cohort study. Results. 100 patients (p) were included. Median age was 27 months (IQR 6-88). Overall 93 p (93%) had an underlying disease, 36 of whom had neutropenia. Eighty-five p (85%) had received antibiotics over the previous month, 60 (60%) had undergone previous invasive procedures, and 81 (81%) had been previously admitted. Forty-two p (42%) were admitted because of septic shock, 56 p (56%) were admitted to the intensive care unit (ICU), and 49 (49%) required mechanical ventilation (MV). Seventeen p (17%) had primary bacteremia, 15 p (15%) had catheter-related bacteremia, and 68 p (68%) had secondary bacteremia. The most common focus was mucocutaneous (21 p), followed by pulmonary (20 p). Emperical treatment was adequate in 84 p (84%). Resistance to one or more groups of antibiotics was observed in 38% of the cases; 11% were multiresistant and 15% were only resistant to carbapenems. Thirty-one p (31%) died. In our series, Pseudomonas aeruginosa resistant to carbapenems only or combined with other antibiotics was associated with previous exposition to antibiotics (p≤0.03), inadequate initial emperical treatment (p≤0.006), and higher mortality (p≤0.01), and longer hospital stay and treatment duration (p≤0.001)

Performance of rapid tests for carbapenemase detection among Brazilian Enterobacteriaceae isolates

ABSTRACT The global emergence of carbapenemases led to the need of developing new methods for their rapid detection. The aim of this study was to evaluate the performance of the rapid tests for carbapenemase-producing and non-producing Enterobacteriaceae. Carbapenem non-susceptible Enterobacteriaceae from a surveillance study submitted to a multiplex real time PCR for carbapenemase detection were included in this study. The isolates were subjected to the rapid phenotypic tests Carba NP, Blue-Carba and Carbapenem Inactivation Method (CIM). A total of 83 carbapenemase-producing (43) and non-producing (40) isolates were included in the study. The sensitivity/specificity were 62.7%/97.5%, 95.3%/100%, and 74.4%/97.5% for Carba NP, Blue-Carba and CIM, respectively. Both Carba NP and Blue-Carba presented their final results after 75 min of incubation; the final results for CIM were obtained only after 8 h. Failure to detect OXA-370 carbapenemase was the main problem for Carba NP and CIM assays. As the Blue-Carba presented the highest sensitivity, it can be considered the best screening test. Conversely, CIM might be the easiest to perform, as it does not require special reagents. The early detection of carbapenemases aids to establish infection control measures and prevent carbapenemases to spread reducing the risk of healthcare associated infections and therapeutic failure.

Performance of "RESIST-3 O.K.N. K-SeT" immunochromatographic assay for the detection of OXA-48 like, KPC, and NDM carbapenemases in Klebsiella pneumoniae in Turkey

ABSTRACT In this study, the performance of the "RESIST-3 O.K.N. K-SeT" (Coris BioConcept, Gembloux, Belgium) immunochromatographic assay was evaluated in 132 Klebsiella pneumoniae comprising 102 carbapenem resistant and 30 carbapenem susceptible isolates. Genotypically known isolates of Gram negative bacteria (n = 22) including various species were also tested by the assay as controls. The isolates tested by the immunochromatographic assay and also were run PCR for bla KPC, bla IMP, bla VIM, bla NDM, and bla OXA-48. The rates of bla NDM, bla OXA-48, and bla KPC in carbapenem resistant isolates were found at 52.9%, 39.2%, and 2.0%, respectively. Both bla NDM and bla OXA-48 were found in six (5.9%) isolates. The results of the assay showed 100% concordance with those obtained by PCR in 132 K. pneumoniae. The agreement between the two methods was found to be identical at the isolate level. The assay also correctly detected all genotypically known isolates of Escherichia coli, Serratia marcescens, Citrobacter freundii, Enterobacter cloacae, K. pneumoniae carrying bla KPC, bla NDM, and/or bla OXA-48. On the other hand, the assay did not exhibit any cross-reaction in control isolates harboring bla IMP and bla VIM. We conclude that the RESIST-3 O.K.N. K-SeT is a reliable, rapid, and user friendly test and we recommend it for routine diagnostic laboratories.