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This work aims to evaluate a rapid detection method of carbapenem resistance genes in blood cultures based on Xpert Carba-R and preliminarily evaluate its clinical application.Methods:Sixteen strains of Enterobacterales carrying different carbapenem resistance genes were selected to prepare simulated positive blood culture samples and Xpert Carba-R was used to directly detect carbapenem resistance genes in the simulated positive blood culture. From January 2022 to June, a prospective study was conducted on a total of 117 Enterobacteriaceae-positive blood culture samples in the First Affiliated Hospital of Nanjing Medical University. Xpert Carba-R, detecting five kinds of carbapenem resistance genes in these samples, was evaluated in sensitivity and specificity compared to polymerase chain reaction sequencing. Meanwhile clinical data of positive patients was collected for prognostic analysis. Results:Of the 16 simulated specimens, 14 strains had carbapenem resistance genes detected by Xpert Carba-R, including 8 bla KPC, 5 bla NDM and 1 bla IMP, showing 100% agreement with the known results. As of the 117 clinical specimens, 28 cases were determined to be Enterobacterales harboring carbapenem resistance genes, including 24 bla KPC, 2 bla NDM and 2 bla KPC+ bla NDM. In comparison to the PCR sequencing, the sensitivity and specificity of Xpert Carba-R were both 100% for blood culture samples, and furthermore, the detection time was significantly reduced. Of the 25 positive patients, 9 cases were treated with monotherapy and 5 cases were effective, other 16 cases received combined treatment and 12 cases were effective. A total of 17 cases were effective, 8 cases were ineffective and 3 of them died, the mortality rate was 12% (3/25). Conclusion:Xpert Carba-R can rapidly and accurately detect carbapenem resistance genes in blood culture, which can provide evidence for rational drug therapy in early clinical stage.
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Estudio cuasi-experimental desarrollado para disminuir el impacto de la resistencia a los antimicrobianos a través de un programa de prevención de infecciones y optimización del uso de antimicrobianos construido "a medida" según las posibilidades de la institución. Se implementó: vigilan-cia de colonización e infección por enterobacterias pro-ductoras de carbapenemasas (EPC); vigilancia y medidas preventivas para infecciones urinarias asociadas a sonda vesical (ITU); vigilancia e intervenciones para mejorar la higiene de manos; guías locales de tratamiento de enfer-medades infecciosas con evaluación de adherencia a las mismas y consumo de antibióticos (ATB). Resultados: Comparando periodo pre y postintervención: tasa de EPC en muestras clínicas: 1,1 a 0/días paciente; razón de tasas de incidencia (IRR: 0.00, p: 0.033); tasa de colonización: 3,3 a 0,61/días paciente (IRR: 0.18, p: 0.5). Tasa de ITU 8,9 a 7,2/1000 días catéter urinario (IRR: 0.81, p 0.5). Adherencia a higiene de manos: 77,5% a 70,38% (p 0.0067). Consumo de ATB: 376,24 a 176,82 DDD, (disminu-ción 53%). Adherencia a guías en elección de ATB: 57,1% a 95,4% (p 0.00031); duración de ATB: 92,8% a 98,4% (p 0.16); adecuación según rescate microbiológico: 57,1% a 100% (p <0.01). Conclusión: Un programa con medidas simples, a medida, con supervisión externa, redujo en un tiempo relativamente corto las infecciones por EPC, el consumo y uso apropiado de ATB en un hospital público de medianos/bajos recursos
This quasi-experimental study was developed in a public hospital with the goal of reducing the impact of antimicrobial resistance through an infection prevention and antimicrobial stewardship program. The following measures were implemented: surveillance of colonization and infection by carbapenemase-producing Enterobacteriaceae (CPE); surveillance and preventive measures for urinary catheter-associated infections (UTIs); surveillance and interventions for hand hygiene; local guidelines for treatment of infectious diseases with compliance and antibiotic (ATB) consumption metrics.Results: comparing the pre-intervention and post-intervention period, CPE rate in clinical samples 1.1 to 0/patient days, incidence rate ratio (IRR): 0.00, p: 0.033 and colonization of 3.3 to 0.61/days patient, IRR: 0.18, p-value: 0.5. UTI rate 8.9 to 7.2/1000 days urinary catheter IRR: 0.81, p 0.5. Hand Hygiene compliance: 77.5% to 70.38%, p 0.0067. ATB consumption: 376.24 to 176.82 DDD, 53% decrease. Compliance to guidelines in ATB selection: 57.1% to 95.4% p 0.00031, duration of ATB from 92.8% to 98.4% p 0.16, and adequacy to microbiological rescue of 57.1% at 100%, p <0.01. Conclusion: it is possible to reduce CPE infections, the consumption of antimicrobials and optimize their use in a public hospital in a country with medium/low resources through a program with basic and tailored measures
Subject(s)
Humans , Male , Female , Drug Resistance, Microbial , Infection Control , Carbapenem-Resistant Enterobacteriaceae , Antimicrobial StewardshipABSTRACT
Objective:To analyze the risk factors of carbapenem-resistant Klebsiella pneumoniae (CRKP) infection in intensive care unit (ICU) patients and to construct a prediction model for infection. Methods:The clinical data of 204 patients with Klebsiella pneumoniae infection admitted in ICU of Jining First Hospital during January 2020 to December 2022 were retrospectively analyzed. Patients admitted during January 2020 to December 2021 were selected as model set ( n=150), and patients admitted during January to December 2022 were selected as validation set ( n=54). In model set, there were 59 cases infected with CRKP (CRKP group) and 91 cases infected with carbapenem-sensitive Klebsiella pneumonia (CSKP group). The risk factor of CRKP infection in ICU patients were analyzed with multivariate Logistic regression, based on which an infection prediction model was constructed. The predictive value of the model was evaluated by ROC, and verified in the validation group. Results:Multivariate Logistic regression analysis showed that empirical use of beta-lactam antibiotics( OR=6.985, 95 % CI 1.658-29.423, P=0.008), central vein catheterization( OR=7.486, 95 % CI 2.776-20.186, P<0.001)and tracheal intubation/incision( OR=10.695, 95 % CI 2.701-42.351, P=0.001)were risk factors for CRKP infection in ICU patients. The regression equation for predicting the risk of infection was -4.851+ empirical use of beta-lactam antibiotics×1.944+ central vein catheterization×2.013+ tracheal intubation/incision×2.370. The area under the ROC curve (AUC) of the model for predicting infection in the model group was 0.905, with sensitivity and specificity of 79.7% and 90.1%, respectively. The AUC of the model for predicting infection in validation group was 0.881, with sensitivity and specificity of 84.2% and 85.7%, respectively. Conclusion:The constructed infection prediction model in the study can effectively predict CRKP infection in ICU patients.
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Objective:To investigate the clinical manifestations and related risk factors of patients with Pseudomonas aeruginosa (PAE) bloodstream infection, and to provide references for clinical diagnosis and treatment of PAE bloodstream infection after combining with bacterial resistance condition. Methods:The clinical data and biological data of all patients with PAE bloodstream infection who received treatment in the Third Affiliated Hospital of Wenzhou Medical University from January 2019 to December 2020 were analyzed retrospectively. The independent influential factors of PAE bloodstream infection were analyzed using binary logistic regression. Results:Eighty-three patients had PAE bloodstream infection. Among them, 71 patients were included in the final analysis. Among the 71 patients, 36 patients (50.70%) had carbapenem-resistant Pseudomonas aeruginosa ( CRPA). Univariate analysis showed that the history of hospitalization within 90 days ( χ2 = 3.90, P = 0.048), indwelling catheterization ( χ2 = 5.08, P = 0.024), septic shock ( χ2 = 4.00, P = 0.046), mechanical ventilation ( χ2= 12.35, P < 0.001), deep venous catheter ( χ2 = 4.08, P = 0.043), acute physiology and chronic health evaluation score II ≥ 10 points ( χ2 = 4.06, P = 0.044), and multi-drug resistance ( χ2 = 11.75, P = 0.001) were the suspicious influential factors of CRPA bloodstream infection. Multivariate logistic regression analysis showed that mechanical ventilation was an independent risk factor for CRPA bloodstream infection ( OR = 7.43, 95% CI 1.182-46.674, P = 0.032). Multi-drug resistance was an independent risk factor for CRPA bloodstream infection ( OR = 5.842, 95% CI 1.520-22.450, P = 0.010). Conclusion:Mechanical ventilation and multi-drug resistance are the independent influential factors of CRPA bloodstream infection. Invasive operations such as mechanical ventilation should be avoided in the clinic.
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Objective:To analyze the risk factors of carbapenem-resistant Klebsiella pneumoniae(CRKP)infection in tumor patients. Methods:The clinical data of hospitalized tumor patients with Klebsiella pneumoniae(KP)infection admitted in Hangzhou Cancer Hospital during January 2021 to December 2022 were retrospectively analyzed. Patients were divided into CRKP group( n=37)and carbapenem-sensitive Klebsiella pneumoniae(CSKP)group( n=142)according to drug sensitivity. The risk factors of CRKP infection were analyzed by univariate and multivariate Logistic regression. Results:Univariate analysis showed that cardiovascular disease( χ2=4.554, P=0.033),carbapenem use ≥7 days( χ2=53.483, P<0.001)and hospital stay >7 days( χ2=3.871, P=0.049)were significantly associated with CRKP infection in tumor patients. Multivariate Logistic analysis showed that carbapenem therapy for ≥7 days( OR=18.280,95% CI 6.533-51.147, P<0.001)was an independent risk factor for CRKP infection in tumor patients. Conclusion:Tumor patients with long-term use of carbapenems are prone to CRKP infection.
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Rising antimicrobial resistance (AMR) is causing therapeutic failures with antibiotics. Inappropriate use is a contributing factor. One such antibiotic on the radar is faropenem, a broad spectrum antibiotic approved in 2005 in India. Recently, faropenem sodium suspension was approved for use in children. There is a potential danger of overuse due to the convenience of oral administration. Other carbapenems such as meropenem are used parenterally. Overuse of faropenem may promote cross-resistance with other carbapenems making them ineffective.
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Resumen Introducción: La problemática de las enterobacterias productoras de carbapenemasas (EPC) se exacerbó con la pandemia por COVID-19 en países con una incidencia previa elevada, como la Argentina. Este estudio describe el desarrollo y resultados de un programa de prevención de EPC, fundamental mente Klebsiellas productoras de carbapenemasas (KPC), en tres unidades críticas de dos hospitales públicos durante 6 meses de la pandemia. Métodos: El objetivo fue reducir la incidencia de KPC en muestras clínicas y de colonización. Este estudio, quasi experimental, se basó en un ciclo de mejora e implementación de tres me didas: higiene de manos, higiene ambiental y vigilancia periódica con hisopados rectales. Resultados: Respecto a las medidas, todas las unidades mejoraron la vigilancia activa y dos de estas tuvieron además mejoría en la higiene de manos e higiene ambiental. Comparando los períodos pre y post intervención en las tres unidades no se observaron cambios significativos en la tasa de muestras clínicas KPC positivas. Se logró disminuir en forma significativa la colonización por KPC en dos unidades (unidad 2: 51.6-18.5 p 0.0004, unidad 3: 62.5-5.2 p < 0.0000001). Todas las unidades mostraron hacia el final del estudio una tendencia al descenso en ambas tasas. Conclusión: Contener o reducir el avance de KPC en nuestra región es posible incluso en escenarios difíciles como el de la pandemia. Se necesitan más estudios en países de ingresos bajos y medianos, para demostrar el impacto de los programas de prevención de KPC en estas situaciones.
Abstract Introduction: The problem of carbapenemase-producing Enterobacteriaceae (CPE) was exacerbated by the COVID-19 pandemic in countries with a previous high incidence, such as Argentina. This study describes the development and results of a CPE prevention program, mainly carbapenemase-producing Klebsiellas (KPC), in three critical units of two public hospitals during 6 months of the pandemic. Methods: The objective was to reduce the incidence of KPC in clinical and colonization samples. This quasi-experimental study was based on a cycle of improvement and implementation of three measures: hand hygiene, environmental hygiene, and periodic surveillance with rectal swabs. Results: Regarding the measures, all the units optimized active surveillance, and two of these also improved hand and environmental hygiene. Comparing the pre- and post-intervention periods in the three units, no significant change was observed in the rate of KPC positive clinical samples. KPC coloni zation was significantly reduced in two units (unit 2: 51.6-18.5 p 0.0004, unit 3: 62.5-5.2 p < 0.0000001). All units showed a downtrend in both rates towards the end of the study. Conclusion: Containing or reducing the advance of the KPC in our region is possible even in difficult scenarios such as the pandemic. More studies are needed in low- and middle-income countries to demonstrate the impact of KPC prevention programs in these situations.
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Resumen Las infecciones hospitalarias causadas por bacilos gram negativos resistentes a carbapenems (BGNCR) están asociadas al aumento de morbimortalidad y gasto sanitario. La identificación mediante cultivos de vigilancia y las medidas de control de infecciones permiten reducir su diseminación. El objetivo del estudio fue evaluar el impacto de un programa de vigilancia integrado a protocolos de control de infecciones sobre la incidencia de BGNCR y conocer su epidemiología molecular en una unidad de cuidados intensivos. Se realizaron auditorías seguidas de un programa de cultivo de vigilancia activa y caracterización molecular de BGNCR, antes y después de la implementación de programas de prevención y control de infecciones. El screening microbiológico se realizó en medios cromogénicos; la caracterización molecular de p-lactamasas (blaKPC, bla0XA-48-like, blaVIM, blaiMP, blaNDM, blaSHV y blaCTx-M) por PCR y la tipificación molecular por PFGE y MLST para Klebsiella pneumoniae. El protocolo desarrollado permitió reducir la colonización global de 16,92% al 9,67%. La diseminación de K. pneumoniae fue a expensas de diversos clones portadores de KPC-2 asociada a BLEE SHV-2 y CTX-M-15, y distribuidos en varios secuenciotipos (ST17, ST13, ST2256, ST353); no se observó persistencia de un clon particular y ningún aislamiento presentó factores de virulencia asociados a hipervi-rulencia. Los aislamientos de Acinetobacter baumannii fueron mayoritariamente productores de IMP-1. El análisis PFGE individualizó 3 clusters, asumiendo que la diseminación fue clonal.
Abstract Hospital-acquired infections caused by carbapenem-resistant Gram-negative bacteria (CRGNB) have been increasingly reported worldwide and are associated with high rates of mortality especially in intensive care units(ICUs). Early identification through rectal surveillance cultures and implementation of infection control measures(ICM) including contact precautions, staff education on cleaning and hand hygiene may reduce the spread of these microorganisms. The aim of this work was to assess the impact of enhanced ICM on CRGNB colonization and to describe the molecular epidemiology of these bacteria in a polyvalent ICU in a tertiary level hospital. A prospective study including audits and active surveillance culture program, with molecular characterization, was conducted before and after the implementation of prevention programs and infection control measures. Microbiological screening was performed in chromogenic media; PCR targeting p-lactamases genes (ó/qkpc, óíQndm, blaviM and blaoxA-48, blasHv and ó/qctx-m), molecular typing by PFGE; and MLST in K. pneumoniae were performed. CRGNB colonization was reduced from 16.92% to 9.67% upon implementing the infection control measures. In K. pneumoniae the most frequent carbapenemase type was KPC-2 associated with SHV-2 and CTX-M-15, and was disseminated in various STs (ST17, ST13, ST2256, ST353); there was no persistence of particular clones and virulence factors showed no association with hypervirulence. IMP-1 carbapenemase predominated in A. baumannii and the PFGE analysis individualized 3 clusters, assuming that the dissemination in the ICU was clonal. The early detection of patients colo-nized with CRBGN by using epidemiological surveillance cultures and the implementation of prophylactic measures are key to reducing the incidence of these microorganisms.
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Objective:This work aims to investigate the phenotype-characteristics of drug resistance and the possible mechanisms of extensively drug-resistance Klebsiella pneumoniae(XDRKP). Methods:Screened by the previous drug susceptibility results, 116 clinical Klebsiella pneumoniae isolates were collected from Shanxi Bethune Hospital from January 2018 to December 2020. Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) rapid microbial identification system and VITEK-compact 2 were used. The modified carbapenem inactivation method (mCIM) combining with EDTA carbapenem inactivation method (eCIM) was used to identify the strains′ carbapenemase phenotypes, which were compared with subsequent qPCR results. The qPCR amplification combining with agarose gel electrophoresis were carried out to detect various drug-resistant related genes, including: carbapenemase genes: blaKPC, blaNDM, blaVIM, blaIMP, blaOXA; aminoglycosides resistance genes: ① 16S rRNA methylase genes: rmtA, rmtC, rmtD, rmtG, rmtH, armA, npmA, rmtB, rmtE, rmtF, ② variant of aminoglycosides acetyltransferase gene: aac(6′)-Ib-cr; quinolone resistance genes: DNA gyrase protection protein qnr family: qnrA, qnrB, qnrC, qnrD, qnrS, efflux pump protein gene: oqxAB, qepA, variant of aminoglycoside acetyltransferase gene: aac(6′)-Ib-cr; and tigecycline-resistant Tet protein genes: efflux pump protein gene: tet (A), tet (L), ribosome protection protein gene: tet (M), tigecycline modified enzyme gene: tet (X). Each isolate′s phenotype and resistance gene result were compared and analyzed correspondingly. Results:A total number of 116 XDRKP isolates were collected in 3 years, 115 of which are identified as carbapenem resistant. Both cephalosporins and quinolones resistant rate were 100%, while the resistant rate of aminoglycosides antibiotic gentamicin, tobramycin and amikacin was 95.69% (111/116), 94.83% (110/116), or 88.79% (103/116) respectively. Sulfonamide antibiotics and tigecycline showed a relatively lower resistant rate. Compared with PCR amplification results, mCIM combining with eCIM phenotype testing had a high conformity, up to 95.65% (110/115). Positive rate of each resistance related gene was: blaKPC 90.52% (105/116), blaNDM 10.34% (12/116), rmtB 81.90% (95/116), armA 2.59% (3/116), oqxAB 65.52% (76/116), qnrB 6.03% (7/116), qnrS 12.93% (15/116), aac(6′)-Ib-cr 7.76% (9/116), or tet(A) 21.55% (25/116), respectively. Other resistance related genes were not detected. Corresponding analysis between the resistant phenotypes and resistance related genes indicated that a total of 65 XDRKP didn′t have a matched pairs, i.e. bacteria′s resistance to specific antibiotic could not be interpreted by carrying some associated resistant genes.Conclusions:The wide distribution of resistant genes and multiple-antibiotic-inactivated trait of some genes(such as aac(6′)-Ib-cr and oqxAB) in XDRKP are potential causes of the generation of extensively drug resistant phenotype. Different XDRKP isolates may carry one or more resistant genes in responding to specific antibiotic. In addition, there are some bacteria with an unmatched phenotype-gene feature indicating that both resistance genes′ regulation and some other mechanisms also play a role in development of XDR.
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Resumen Introducción: La resistencia a carbapenémicos en bacilos gramnegativos es un problema de salud pública mundial, debido a que se asocia con altas tasas de mortalidad, aumento en los niveles de resistencia a otros antimicrobianos, elevación en el potencial de diseminación e incremento en los costos de atención en salud. Objetivo: Caracterizar bacilos gramnegativos multirresistentes, aislados en pacientes hospitalizados en instituciones de salud de Barranquilla (Colombia). Material y Métodos: Estudio descriptivo acerca de la caracterización fenotípica y genotípica de la resistencia bacteriana en las infecciones asociadas a la atención en salud, mediada por carbapenemasas en aislados bacterianos enviados por los laboratorios pertenecientes a la red de laboratorios del Departamento del Atlántico. Resultados: La KPC fue la carbapenemasa más frecuente en las Enterobacterales (27,6%), predominando en Klebsiella pneumoniae (13,1%) sola y asociada a otras carbapenemasas. En Pseudomonas aeruginosa predominó la carbapenemasa VIM (32,8%) y la OXA en Acinetobacter baumannii (17,1%). Conclusión: Se encontró una amplia distribución de cepas multi-resistentes productoras de carbapenemasas en instituciones de salud de Barranquilla, las cuales expresaron los siguientes mecanismos de resistencia: KPC, VIM, NDM, OXA.
Abstract Background: The emergence of carbapenem resistant gramnegative bacilli has become a problem of public health worldwide, because it is associated with high mortality rates, increased levels of resistance to other antimicrobials, increased potential for dissemination transition and increase in health care costs. Aim: To characterize multiresistant gram-negative bacilli, isolated in patients hospitalized in health institutions of Barranquilla (Colombia). Methods: A descriptive study was conducted on the phenotypic and genotypic characterization of bacterial resistance in infections associated with health care, mediated by carbapenemases in bacterial isolates sent by laboratories belonging to the laboratory network of the Department of Atlántico. Results: KPC was the most frequent carbapenemase in Enterobacterales (27.6%), predominantly in Klebsiella pneumoniae (13.1%) alone and associated with other carbapenemases. In Pseudomonas aeruginosa, VIM carbapenemase (32.8%) predominated and OXA in Acinetobacter baumannii (17.1%). Conclusion: A wide distribution of multi-resistant strains producing carbapenemases in Atlantic health institutions was found, which expressed the following resistance mechanisms: KPC, VIM, NDM, OXA.
Subject(s)
Humans , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Young Adult , beta-Lactamases/genetics , Acinetobacter baumannii , Bacterial Proteins , Carbapenems , Colombia , Drug Resistance, Multiple, Bacterial , Gram-Negative Bacteria , Klebsiella pneumoniae , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/pharmacologyABSTRACT
Background and Objectives: carbapenem resistance in Acinetobacter baumannii has reached extremely high levels worldwide, and class D OXA-type carbapenemases are the main associated mechanism. This study aimed to assess the phenotypic and molecular profile of clinical carbapenem-resistant A. baumannii (CRAb) isolates from a southern Brazilian border region. Methods: A. baumannii species was identified by the presence of the blaOXA-51 gene, and the susceptibility profile was determined by broth microdilution. The main carbapenemases were investigated by PCR and the molecular typing was performed by PFGE. Results: during the study, a total of 36 CRAb were recovered, of which 85.7% were from respiratory tract samples from ICU patients. High level resistance to were found in contrast to 100% of susceptibility for polymyxin B. The blaOXA-23 gene was present in 34 isolates and was the only one detected other than blaOXA-51. Molecular typing revealed the presence of four clonal strains, two of them endemic during the period of the study. Conclusion: to the best of our knowledge, our study brings the first data about resistance profile in Acinetobacter in the western border of southern Brazil and make aware of endemic clones of CRAb-producing-OXA-23 in this region of state, contributing for the construction of the national epidemiologic scenario of CRAb.(AU)
Justificativa e Objetivos: a resistência aos carbapenêmicos em Acinetobacter baumannii atingiu níveis extremamente altos em todo o mundo, e as carbapenemases do tipo OXA classe D são o principal mecanismo associado. O objetivo deste estudo foi avaliar o perfil fenotípico e molecular de isolados clínicos de A. baumannii resistentes aos carbapenêmicos (CRAb) de uma região de fronteira do sul do Brasil. Métodos: a espécie A. baumannii foi identificada através da presença do gene blaOXA-51, e o perfil de sensibilidade foi determinado por microdiluição em caldo. As principais carbapenemases foram investigadas por PCR, e a tipagem dos isolados de CRAb foi realizada por PFGE. Resultados: durante o período do estudo, 36 CRAb foram recuperados, dos quais 85,7% foram provenientes de amostras do trato respiratório de pacientes de UTI. Uma elevada resistência a aminoglicosídeos e fluoroquinolonas foi encontrada em contraste com 100% de sensibilidade a polimixina B. O gene blaOXA-23 foi encontrado em 34 isolados e foi o único detectado além do blaOXA-51. A tipagem molecular revelou a presença de quatro linhagens clonais, duas delas endêmicas ao longo do período do estudo. Conclusão: nosso estudo traz os primeiros dados sobre o perfil de resistência em Acinetobacter na fronteira oeste do sul do Brasil e alerta para a presença de clones endêmicos de CRAb produtores de OXA-23 nessa região, contribuindo para a construção do cenário epidemiológico nacional de CRAb.(AU)
Justificación y Objetivos: la resistencia a carbapenémicos en Acinetobacter baumannii ha alcanzado niveles extremadamente altos en todo el mundo y las carbapenemases OXA de clase D son el principal mecanismo asociado. El objetivo de este estudio fue evaluar el perfil fenotípico y molecular de los aislados clínicos de A. baumannii resistentes a carbapenémicos (CRAb) de una región fronteriza en el sur de Brasil. Métodos: la especie A. baumannii se identificó a través de la presencia del gen blaOXA-51 y el perfil de sensibilidad se determinó por microdilución en caldo. Las principales carbapenemasas fueron investigadas por PCR y la tipificación se hizo con PFGE. Resultados: durante el período de estudio, se recuperaron 36 CRAb, 85,7% de muestras del tracto respiratorio de pacientes de la UCI. Se encontró una alta resistencia a los aminoglucósidos y las fluoroquinolonas en contraste con 100% de sensibilidad a polimixina B. El gen blaOXA-23 se encontró en 34 aislamientos y fue el único detectado además de blaOXA-51. La tipificación molecular reveló la presencia de cuatro cepas clonales, dos de ellas endémicas durante el período de estudio. Conclusiones: hasta donde sabemos, nuestro estudio trae los primeros datos sobre el perfil de resistencia en Acinetobacter en la frontera oeste del sur de Brasil y reconoce los clones endémicos de CRAb productores de OXA.(AU)
Subject(s)
Acinetobacter Infections/epidemiology , Drug Resistance, Microbial , Carbapenem-Resistant Enterobacteriaceae , Carbapenems , Acinetobacter baumanniiABSTRACT
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.
Subject(s)
Humans , Pseudomonas aeruginosa , Pseudomonas Infections , Pseudomonas aeruginosa/genetics , Bacterial Proteins/genetics , beta-Lactamases/genetics , Microbial Sensitivity Tests , Carbapenems/pharmacology , Chile , Hospitals , Anti-Bacterial Agents/pharmacologyABSTRACT
Resumen Introducción: Acinetobacter baumannii es la bacteria Gram negativa asociada a infecciones intrahospitalarias por su gran facilidad de supervivencia en condiciones adversas y el desarrollo de multirresistencia a diversos antimicrobianos. Durante años se han registrado brotes hospitalarios en diferentes países asociados a esta bacteria, lo que aumentó el interés de estudio de las biopelículas y los genes involucrados en su producción, debido a que se demostró una asociación a la resistencia antibiótica. Objetivos: Establecer relacion entre la multirresistencis a los diferentes antibioticos y la formacion de biopeliculas en aislamientos de Acinetobacter baumannii. Métodos: Se estudió cepas de Acinetobacter baumannii utilizando reacción en cadena de la polimerasa (PCR) en tiempo real para la detección de genes bap, csuE, ompA, oxa-51 de 191 muestras, de igual manera se realizó la cuantificación de la biopelícula formada siguiendo la técnica descrita por Badmasti y Azizi. Resultados: Se realizó este estudio sobre 191 cepas de Acinetobacter baumannii provenientes de dos centros hospitalarios para la identificación de genes asociados a las biopelículas y posterior cuantificación de acuerdo a la técnica descrita por Badmasti y Azizi. Demostrando una asociación entre las biopelículas y la resistencia bacteriana de Acinetobacter baumannii. Conclusiones: Los resultados demostraron una asociación positiva entre la cantidad de biopelícula formada y la resistencia antibiótica, bacterias formadoras fuertes de biopelículas presentan mayor resistencia a los carbapenems. En cuanto a los genes, el gen ompA demostró una asociación con la cantidad de biofilm producido, bap y csuE son genes involucrados en el primer paso de formación de biofilm, pero no se asocian con la cantidad formada por la bacteria.
Abstract Introduction: Acinetobacter baumannii is the Gram-negative bacterium associated with hospital infections due to its great ease of survival in adverse conditions and the development of multi-resistance to various antimicrobials. For years, hospital outbreaks have been registered in different countries associated with this bacterium, which increased the interest in studying biofilms and the genes involved in their production, since an association with antibiotic resistance was demonstrated. Objectives: To establish a relationship between multiresistance to different antibiotics and biofilm formation in Acinetobacter baumannii isolates. Methods: acinetobacter baumannii strains were studied using real-time polymerase chain reaction (PCR) for the detection of bap, csuE, ompA, oxa-51 genes from 191 samples, in addition to the quantification of the biofilm formed following the technique described by Badmasti and Azizi. Results: this study was carried out on 191 Acinetobacter baumannii strains from two hospital centers for the identification of genes associated with biofilms and subsequent quantification according to the technique described by Badmasti and Azizi. Demonstrating an association between biofilms and Acinetobacter baumannii bacterial resistance. Conclusions: the results demonstrated a positive association between the amount of biofilm formed and antibiotic resistance. Strong biofilm-forming bacteria show greater resistance to carbapenems. Regarding the genes, the ompA gene showed an association with the amount of biofilm produced, bap and csuE are genes involved in the first step of biofilm formation, but they are not associated with the amount formed by the bacteria
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Objective:Evaluate the application of Fourier transform infrared spectroscopy in the identification of homology of carbapenem-resistant Escherichia coli(CREC). Methods:A total of 26 carbapenem-resistant Escherichia coli strains were isolated from 9 provinces in China in 2018. The 900-1 200 cm -1 was selected as a spectral region for the Euclidean distance calculating and average linkage clustering between all isolates.The single nucleotide polymorphism (SNP) was analyzed by whole genome sequencing (WGS). Results:Twenty-six CREC strains were divided into 14 infrared spectros copy(IR) types by FTIR. The same IR type belonged to the same sequence type type.Compared with cluster analysis based on WGS, the consistency of FTIR cluster analysis was 92.3% (24/26).Conclusions:FTIR presented excellent performance in identification of homology of CREC.Besides, with the advantages of simple operation and rapid acquisition of results, FTIR may be a useful tool in clinical labs.
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OBJECTIVE:To esta blish a special management system of carbapenems ,and to standardize the clinical and rational application of carbapenem antibacterial drugs. METHODS :According to the requirements of the relevant documents of National Health Commission of the People ’s Republic of China ,the special management system of carbapenems in the First Affiliated Hospital of University of Science and Technology of China (called“our hospital ”in short )was constructed. The use intensity,reasonable rate of prescription and the detection rate of carbapenem resistant Enterobacteriaceae were analyzed before and after management. RESULTS :The special management system of carbapenems in our hospital included organization construction,information construction of special management ,prescription review of special management drugs ,prescription comment intervention and so on. After the implementation of the special management system ,the intensity of carbapenems use decreased from 2.78 to 2.03,the reasonable rate of prescription increased from 62.8% to 98.3%(P<0.05). The detection rates of Acinetobacter baumannii ,Escherichia coli and Pseudomonas aeruginosa resistance to carbapenems decreased from 91.4%,2.4%, 49.5% to 79.7%,1.6%,39.7%,respectively. However ,the detection rate of Klebsiella pneumoniae resistance to imipenem increased from 34.4% to 50.0%. CONCLUSIONS :The special management system of carbapenems in our hospital has achieved some results in practice ,which helps to reduce the abuse of these drugs and improve the reasonable level of drug use and reduce the detection rate of drug-resistant bacteria. At the same time ,hospital infection control of K. pneumoniae resistance to imipenem should be strengthened.
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OBJECTIVE:To provide reference for the ra tional use of carbap enems in tuberculosis patients. METHODS :Totally 12 576 tuberculosis inpatients were collected from our hospital. Multi-disciplinary team (MDT) model was adopted for carbapenems management in aspects of policy intervention ,technical support and staff training. Average hospitalization duration , mortality,nosocomial infective rate ,use and drug resistance of carbapenems were compared before (Mar. 2016-Mar. 2017)and after management (Apr. 2017 to Mar. 2019). Interrupted time series (ITS)analysis was used to analyze the utilization rate of carbapenems,DDDs,the proportion of carbapenems ’DDDs in the total antibiotics ’DDDs,the proportion of carbapenems ’cost in the total antibiotics ’cost before and after management. Pearson correlation analysis was conducted for DDDs of carbapenems with medical quality indicators and detection rate of carbapenems-resistant bacteria. RESULTS :After the management ,average hospitalization stay ,the cost of antibiotics ,DDDs of carbapenems ,the proportion of carbapenems ’DDDs in the total antibiotics ’ DDDs,the proportion of carbapenems ’cost in the total antibiotics ’cost,the utilization rate of carbapenems ’,and the drug resistance rate of some bacteria to carbapenems were significantly lower than those before the management (P<0.05). ITS analysis results showed that after management ,the utilization rate of carbapenems ,DDDs,the proportion of com carbapenems’DDDs in the total antibiotics ’DDDs and the proportion of carbapenems ’cost in the total antibiotics ’cost hhyyzj@126.com were decrease d by 4.491% ,220.276,6.535% ,11.747% , with statistical significance (P<0.05). Co mpared with before management ,above indexes were decreased by 0.330%,17.625, 0.308%,0.304% monthly,among which the utilization rate and DDDs of carbapenems were decreased significantly (P<0.05). Before management ,drug resistance rate of Pseudomonas aeruginosa to carbapenems was 21.80%,and those of Acinetobacter baumannii to meropenem and imipenem were both 4.60%;after management ,drug resistance rate of P. aeruginosa to imipenem was 13.00%,and those of A. baumannii to meropenem and imipenem were both 16.30%,with statistical significance before and after management (P<0.05). There was no statistical significance in drug resistance rate of Enterobacteriaceae (P>0.05). Pearson correlation analysis showed that carbapenems ’DDDs was significantly positively correlated with average hospitalization duration and antibiotics ’cost(P<0.05);imipenem’s DDDs was positively correlated with drug resistance rate of P. aeruginosa (P<0.05). CONCLUSIONS: MDT management can effectively standardize the use of carbapenem in tuberculosis patients , shorten hospitalization duration ,and reduce drug cost ,DDDs and drug resistance rate of some bacteria.
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Objective:To investigate the in vitro antibacterial effects of imipenem combined with common antibiotics on bla KPC-2 type carbapenem resistant klebsiella pneumoniae (CRKP) targeting bla KPC-2 gene. Methods:Six strains of unrepeated bla KPC-2 type confirmed by polymerase chain reaction and DNA sequence were isolated in Yueqing People's Hospital, China between January 2018 and January 2019 were included in this study. The susceptibility rate of imipenem against nine conventionally used antibiotics was determined. The sensitivity test of imipenem combined with eight antibiotics was performed with the checkerboard method. Fractional inhibitory concentration was calculated to assess the efficacy of imipenem combined with common antibiotics. The in vitro treatment time-antibacterial effect curve was drawn to evaluate the antibacterial effects. Results:The resistance rate of six strains of bla KPC-2 type was 100.00% (6/6) for imipenem, meropenem, ceftazidime, ciprofloxacin, rifampicin and cefotaxime, and it was 66.67% (4/6) for minocycline and clavulanic acid and 33.33% (2/6) for tigecycline. Imipenem combined with tigecycline had a better antibacterial effect and exhibited a synergistic effect on four strains of bla KPC-2 type CRKP and an additive effect on two strains of Bla KPC-2 type CRKP. The curve of time for in vitro treatment of KPN2 with imipenem combined with tigecycline against bactericidal effect revealed that the antibacterial rate of imipenem at the 1/2 minimum inhibitory concentration combined with tigecycline at the 1/4 minimum inhibitory concentration was > 95% at (t+2) and the antibacterial effect could maintain (t+10) hours to (t+12) hours. The antibacterial rate of imipenem combined with tigecycline against strain 002 was gradually decreased with time, and the growth curve of strain 002 rised gradually. Conclusion:In vitro drug sensitivity test revealed that imipenem combined with tigecycline exhibits a good synergistic effect on bla KPC-2 type CRKP. Findings from this study provide a reference for clinical treatment of bla KPC-2 type CRKP.
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RESUMEN Con el objetivo de determinar la utilidad de la citometría de flujo para la detección de Pseudomonas aeruginosa productoras de metalobetalactamasas (MBL), se estudiaron aislamientos de P. aeruginosa genotípicamente caracterizados del cepario del laboratorio de Epidemiología Molecular y Genética de la Universidad Nacional Mayor de San Marcos. Se analizaron 29 aislamientos (17 productoras de MBL y 12 no productoras de MBL) con el kit de viabilidad celular FACSCalibur (Becton Dickinson). Se utilizaron dos tratamientos, uno con meropenem y el otro con meropenem-EDTA. Usando la razón de aumento de fluorescencia en las células no vivas, se demostró una diferencia significativa entre las productoras de MBL y las no MBL, considerando como punto de corte una razón >1,6. Se determinó una sensibilidad de 94,1% y una especificidad del 100%. La citometría de flujo constituye una alternativa para la detección de P. aeruginosa productora de MBL.
ABSTRACT In order to determine the utility of flow cytometry for detecting metallo-beta-lactamase (MBL)-producing Pseudomonas aeruginosa, we used genotypically characterized P. aeruginosa isolates from the Molecular Epidemiology and Genetics Laboratory of the Universidad Nacional Mayor de San Marcos. A total of 29 isolates (17 MBL-producing and 12 non-MBL-producing) were analyzed with the FACSCalibur (Becton Dickinson) cell viability kit. Two treatments were used, one with meropenem and the other with meropenem-EDTA. A significant difference between MBL and non-MBL-producing P. aeruginosa was demonstrated using the fluorescence ratio in non-living cells, considering a cut-off point of >1.6. We determined a sensitivity of 94.1% and a specificity of 100%. Flow cytometry represents an alternative for the detection of MBL-producing P. aeruginosa.
Subject(s)
Pseudomonas aeruginosa , Molecular Epidemiology , Flow Cytometry , beta-Lactamases , Carbapenems , beta-Lactam ResistanceABSTRACT
Resumen La cinética de la procalcitonina es útil para reducir la duración de la antibioticoterapia en pacientes críticos, pero no se analizó su rol en infecciones por gérmenes multirresistentes. Se realizó un estudio observacional retrospectivo, analizando las curvas de procalcitonina de pacientes con neumonías asociadas a ventilación mecánica (NAVM) y bacteriemias asociadas a catéter (BAC) con rescate bacteriano durante el período 1/11/16 a 1/7/19. Se estudiaron 16 pacientes con infección por gérmenes sensibles (10 BAC y 6 NAVM) y 10 por gérmenes multirresistentes (10 BAC y 10 NAVM). Los pacientes con BAC generadas por gérmenes multirresistentes presentaron valores de procalcitonina mayores que los pacientes con BAC por gérmenes sensibles: (39 ± 30 μg/l vs. 10.7 ± 11 μg/l, p = 0.02). Los pacientes con NAVM generada por gérmenes sensibles y multirresistentes presentaron valores de procalcitonina similares. El descenso de procalcitonina a niveles 80% menores al valor máximo o menores a 0.5 μg/l (con tratamiento antibiótico efectivo) fue más veloz en pacientes con infección por gérmenes sensibles (5 ± 1.8 días vs. 7.2 ± 2.9 días, p = 0.03). En las infecciones por gérmenes multirresistentes, la respuesta inflamatoria medida por procalcitonina fue más intensa y prolongada, aun con un tratamiento antibiótico efectivo. Sin embargo, el descenso se produjo antes de que finalizaran los esquemas antibióticos convencionales. Por este motivo, se considera necesario estudiar la potencial utilidad de protocolos antibióticos guiados por procalcitonina en pacientes con infecciones por gérmenes multirresistentes para reducir la exposición a antibióticos.
Abstract Procalcitonin guidance stimulates a reduction in the duration of antibiotic treatment in critically ill patients with a presumed bacterial infection, but its role in infections caused by multidrug-resistant bacteria has not been sufficiently explored. In this retrospective observational study, we analyzed procalcitonin curves of 32 patients with culture-confirmed ventilation-associated pneumonia (VAP) and catheter-related bloodstream infections (CRBSI) occurred during the period 11/1/2016 to 7/1/2019. Sixteen infections were caused by multidrug-resistant bacteria (10 CRBSI and 6 VAP) and other 16 by sensitive bacteria (10 CRBSI and 6 VAP). CRBSI generated by multidrug-resistant bacteria elicited significantly higher procalcitonin levels than CRBSI infections caused by sensitive bacteria (39 ± 30 μg/l vs. 10.7 ± 11 μg/l, p = 0.02). Patients with VAP caused by sensitive and multidrug-resistant bacteria elicited similar procalcitonin levels. The time to a decrease in procalcitonin level to less than 80% of the peak value or less than 0.5 μg/l upon effective antibiotic treatment was 7.2 ± 2.9 days in multidrug-resistant bacteria vs. 5 ± 1.8 days in sensitive bacteria (p = 0.03). In multidrug-resistant bacteria, the inflammatory response measured by procalcitonin is stronger and longer, even with an effective antibiotic treatment. However, the decline occurs before the conventional antibiotic scheme is completed. The potential application of antibiotic protocols guided by procalcitonin to these groups of patients grants further studies aimed to reduce exposure to antibiotics in critical multidrug-resistant infections.
Subject(s)
Humans , Bacterial Infections/drug therapy , Procalcitonin , Kinetics , Intensive Care Units , Anti-Bacterial Agents/therapeutic useABSTRACT
Abstract Background Gram-negative bacilli (GNB), notably Acinetobacter spp., Pseudomonas spp., and Klebsiella spp., are becoming increasingly resistant to carbapenems and are associated with high health care costs and mortality, becoming a global concern. Objective To determine the prevalence rates of carbapenem resistance among Acinetobacter spp., Pseudomonas spp., and Klebsiella spp. in the main sites of nosocomial infection at a tertiary care hospital in southern Brazil and the consequent therapeutic implications. Methods Cultures processed at the institution's laboratory in 2017 were analyzed, and those positive for Acinetobacter spp., Pseudomonas spp., and Klebsiella spp. were identified. Antibiograms were evaluated for meropenem sensitivity following the Clinical Laboratory Standards Institute guidelines. Results Acinetobacter spp. had the lowest prevalence among the three GNB, and resistance of this pathogen to meropenem at different sites of infection ranged from 36% (blood) to 82% (respiratory tract). Pseudomonas spp. was highly prevalent at the respiratory tract (31%) and had a high resistance rate to meropenem in rectal swab samples (71%), but a relatively low frequency at infection sites (skin/soft tissue, 13%; blood, 25%). Klebsiella spp. was identified in 7.5% of the blood cultures and 15% of the urine cultures and was the chief colonizer among all pathogens, representing 54% of all rectal swab samples, of which 53% were meropenem resistant. At sites of infection, rates of Klebsiella spp. resistant to meropenem ranged from 19% (skin) to 55% (vascular catheter). Conclusions The prevalence of carbapenem-resistant GNB at our hospital was relatively low compared to national and international data; thus, meropenem remains a good therapeutic option against these bacteria. Other antibiotics effective against GNB, such as ceftazidime, cefepime, and piperacillin-tazobactam, can be used in most cases, while meropenem should be reserved for patients with sepsis. Strict contact precaution measures are still needed, given the high resistance rate observed at the colonizing site.