Rapid antibiotic susceptibility testing (RAST) of blood cultures in enterobacteria with inducible chromosomal AmpC-type ß-lactamase.

INTRODUCTION: Early and adequate treatment of bloodstream infections decreases patient morbidity and mortality. The objective is to develop a preliminary method for rapid antibiotic susceptibility testing (RAST) in enterobacteria with inducible chromosomal AmpC. METHODS: RAST was performed directly on spiked blood cultures of 49 enterobacteria with inducible chromosomal AmpC. Results were read at 4, 6 and 8h of incubation. Commercial broth microdilution was considered the reference method. Disks of 10 antibiotics were evaluated. RESULTS: The proportion of readable tests at 4h was 85%. All RAST could be read at 6 and 8h. For most antibiotics, the S or R result at 4, 6 and 8h was greater than 80% after tentative breakpoints were established and Area of Technical Uncertainty was defined. CONCLUSIONS: This preliminary method seems to be of practical use, although it should be extended to adjust the breakpoints and differentiate them by species.

Rapid antibiotic susceptibility testing (RAST) of blood cultures in enterobacteria with inducible chromosomal AmpC-type B-lactamase / Pruebas rápidas de sensibilidad antibiótica de hemocultivos con enterobacterias portadoras de B-lactamasa tipo AmpC cromosómica inducible

Introduction: Early and adequate treatment of bloodstream infections decreases patient morbidity and mortality. The objective is to develop a preliminary method for rapid antibiotic susceptibility testing (RAST) in enterobacteria with inducible chromosomal AmpC. Methods: RAST was performed directly on spiked blood cultures of 49 enterobacteria with inducible chromosomal AmpC. Results were read at 4, 6 and 8h of incubation. Commercial broth microdilution was considered the reference method. Disks of 10 antibiotics were evaluated. Results: The proportion of readable tests at 4h was 85%. All RAST could be read at 6 and 8h. For most antibiotics, the S or R result at 4, 6 and 8h was greater than 80% after tentative breakpoints were established and Area of Technical Uncertainty was defined. Conclusions: This preliminary method seems to be of practical use, although it should be extended to adjust the breakpoints and differentiate them by species.(AU)

Introducción: El tratamiento precoz y adecuado de las bacteriemias disminuye la morbilidad y mortalidad de los pacientes. El objetivo es desarrollar un método preliminar de pruebas rápidas de sensibilidad antibiótica (PRSA) en enterobacterias con AmpC cromosómica inducible. Métodos: Las PRSA se realizaron directamente de hemocultivos simulados positivos para 49 enterobacterias con AmpC cromosómica inducible. Los resultados se leyeron a las 4, 6 y 8 horas de incubación. La microdilución en caldo comercial se consideró el método de referencia. Se evaluaron discos de 10 antibióticos. Resultados: La proporción de pruebas legibles a las 4 horas fue del 85%. Todas las PRSA pudieron leerse a las 6 y 8 horas. Para la mayoría de los antibióticos, el resultado S o R a las 4, 6 y 8 horas fue superior al 80%, después de que se establecieran puntos de corte provisionales y se definiera el área de incertidumbre técnica. Conclusiones: Este método preliminar parece ser de utilidad práctica, aunque debería ampliarse para ajustar los puntos de corte y diferenciar por especies.(AU)

Aplicación de la PCR múltiple ALLPLEX TM ENTERO-DR en un protocolo de aislamiento por enterobacterias multirresistentes en el Complejo Hospitalario Universitario de Albacete / Multiple PCR ALLPLEX TM ENTERO-DR for multidrug- resistant Enterobacteriaceae management at Albacete University Hospita

Fundamentos: Las enterobacterias multirresistentes (EBMR) suponen una amenaza para la Salud Pública, siendo el cribado y aislamiento de pacientes colonizados importante para evitar su diseminación. La PCR múltiple es una técnica novedosa, capaz de proporcionar un diagnóstico rápido con sensibilidad y especificidad altas. El objetivo de este trabajo fue evaluar la aplicación de PCR múltiple en el protocolo de aislamiento por EBMR desde su implantación en nuestro centro. Métodos: Se realizó un estudio observacional descriptivo y retrospectivo. Se analizaron los resultados del estudio de colonización por EBMR a pacientes hospitalizados, mediante PCR múltiple ALLPLEX TM ENTERO-DR, entre noviembre de 2019 y mayo de2021. Se calcularon las frecuencias de resultado positivo, negativo, no interpretable o inválido, de microorganismos identificados, el motivo de petición y actuación posterior. Se calcularon la mediana y Rango Intercuartílico (R.I.) del tiempo desde el cribado hasta el resultado parcial y final. También se calcularon la mediana y R.I. desde el antecedente de colonización/infección según resultado de la prueba rápida. Resultados: Se detectó mecanismo de resistencia en el 31,47% de las pruebas, siendo más frecuentemente aislado E. coli BLEE (68,99%). La mediana de tiempo hasta el resultado parcial fue de 5,75 horas (R.I.: 2,67), existiendo diferencias estadísticamente significativas con el tiempo de cultivo teórico. El motivo principal de petición fue cribado por antecedente (80,12%) y la actuación más frecuente fue no aislar (41,70%). El 14,81% de las pruebas fue positivo si el antecedente de infección/colonización era mayor a cuarenta y nueve meses. Conclusiones: La PCR múltiple es una prueba útil para el control de la colonización por EBMR, que disminuye el tiempo hasta resultado y facilita la toma de decisiones rápidas, pudiendo contribuir a la adecuada gestión de recursos y comodidad de pacientes.(AU)

Background: Multi-resistant Enterobacteriaceae (MRE) are a public health threat, with screening and isolation strategies beingimportant to stop its dissemination. Multiplex PCR is a novel method capable of rapid diagnosis with high sensitivity and specificity. In this study, our objective was to evaluate its application to multidrug-resistant Enterobacteriaceae management since its implementation in our hospital. Methods: An observational retrospective descriptive study of multiplex PCR ALLPLEX TM ENTERO-DR results to screen inpatients colonized by MRE took place from November 2019 to May 2021. We calculated the percentage of positive, negative, non-identifiable or invalid results, identified microorganisms, reason for requesting it and subsequent actions. Median and I.R. from sampling time to partial and theoretical culture time, and since last colonization/infection depending on test results were calculated. Results: Resistance mechanisms were detected in 31.47% of tests, being E. coli ESBL (68.99%) the most frequently isolated microorganism. Median time to partial result was 5.75 hours (I.R.: 2.67), having statistically significant differences with theoretical time. The most important reason to request the test was screening (80.12%) and the most frequent action taken was not to isolate (41.70 %). Whenever forty-nine months or more since last colonization/infection have passed, only 14.81% of the samples tested positive. Conclusions: Multiplex PCR is a useful test to manage colonized patients, capable of giving a rapid result and allowing for quicker decision-making, contributing to a good use of resources and patient comfort.(AU)

Treatment of severe infections caused by ESBL or carbapenemases-producing Enterobacteriaceae / Tratamiento de las infecciones severas causadas por enterobacterias productoras de beta lactamasas de espectro extendido (BLEE) y carbapenemasas

Enterobacteriaceae are the most frequent pathogens in the Intensive Care Unit. Due to their safety and activity, β-Lactams (BL) and carbapenems represented the most common strategy adopted against these germs. The increasing exposure to these molecules led to the development of several types of antimicrobial resistance as the expression of extended-spectrum β-lactamases (ESBLs) and carbapenemases. Great molecular variability exists among these enzymes, with significant clinical impact. To limit morbidity and mortality, old antibiotics were tested and represent viable alternatives for specific types of infections, or once the spectrum of susceptibility of each germ has been determined. Alongside, new molecules have been specifically designed but enzyme molecular variability prevents the existence of one single antibiotic which fits for all. Therefore, a quicker identification of the molecular identity of each germ, together with the knowledge of the activity spectrum of each antibiotic is crucial to tailor the therapy and make it effective. (AU)

Las enterobacterias son patógenos cada vez más frecuentes en las unidades de cuidados intensivos. Los antibióticos beta lactámicos y carbapenémicos representan las estrategias más comunes contra estos gérmenes, debido a sus mecanismos de acción y seguridad clínica. La exposición cada vez mayor de los patógenos a dichas moléculas ha llevado al desarrollo de nuevas diferentes resistencias a los antibióticos, representadas por la expresión de las beta lactamasas de espectro extendido y de las carbapenemasas. Esas enzimas manifiestan mucha variabilidad molecular, que resulta en un sustancial impacto clínico. Una opción disponible y válida para limitar la morbilidad y la mortalidad de estas infecciones es volver a utilizar los viejos antibióticos, una vez que se haya averiguado el espectro de sensibilidad de los gérmenes. Además, nuevos antibióticos han sido específicamente diseñados para solucionar el problema de las resistencias. Sin embargo, la variabilidad molecular de las enzimas hace que sea muy difícil encontrar una única molécula que funcione para todas. Por lo tanto, una rápida identificación de la identidad molecular de los gérmenes, junto a la comprensión detallada del espectro de actividad de cada antibiótico, es de vital importancia para adaptar el tratamiento y hacerlo más efectivo (AU)

Treatment of severe infections caused by ESBL or carbapenemases-producing Enterobacteriaceae.

Enterobacteriaceae are the most frequent pathogens in the Intensive Care Unit. Due to their safety and activity, ß-Lactams (BL) and carbapenems represented the most common strategy adopted against these germs. The increasing exposure to these molecules led to the development of several types of antimicrobial resistance as the expression of extended-spectrum ß-lactamases (ESBLs) and carbapenemases. Great molecular variability exists among these enzymes, with significant clinical impact. To limit morbidity and mortality, old antibiotics were tested and represent viable alternatives for specific types of infections, or once the spectrum of susceptibility of each germ has been determined. Alongside, new molecules have been specifically designed but enzyme molecular variability prevents the existence of one single antibiotic which fits for all. Therefore, a quicker identification of the molecular identity of each germ, together with the knowledge of the activity spectrum of each antibiotic is crucial to tailor the therapy and make it effective.

Impact of infections and extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae on graft and patient survival in a kidney transplantation program in Mexico.

INTRODUCTION: Immunosuppressive treatments have improved graft and patient survival rates, but can increase the incidence of post-transplant infections. OBJECTIVES: To analyze data from kidney transplant patients and describe the pathogens responsible for the infections they experience. METHODS: Longitudinal, analytical, observational study of 103 patients who underwent kidney transplantation. The follow-up period was 5.07 ± 1.28 years. RESULTS: Overall mortality rate was 10.68% and graft loss rate was 14.56%. Regarding recipient risk of death, the Cox regression model showed a hazard ratio (HR) of 5.66 for positive bacterial cultures and 2.22 for positive extended-spectrum beta-lactamase (ESBL)-producing strains; as for graft loss, HR was 4.59 in those with positive bacterial cultures and 4.25 in those who were positive for ESBL-producing strains. CONCLUSIONS: Significant death risk was found in kidney transplant recipients with positive bacterial cultures and an increased risk of graft loss in those with positive bacterial cultures and in those who were positive for ESBL-producing Enterobacteriaceae isolates. The rate of ESBL-producing Enterobacteriaceae is high, and stricter strategies are therefore necessary to control the use of antibiotics.

INTRODUCCIÓN: Los tratamientos inmunosupresores han mejorado las tasas de supervivencia del injerto y del paciente, pero pueden incrementar las infecciones postrasplante. OBJETIVOS: Analizar los datos de pacientes con trasplante renal y describir las bacterias responsables de las infecciones que presentan. MÉTODOS: Estudio observacional, longitudinal y analítico de 103 pacientes sometidos a trasplante renal. El periodo de seguimiento fue de 5.07 ± 1.28 años. RESULTADOS: La tasa de mortalidad fue de 10.68 % y la de pérdida del injerto de 14.56 %. Respecto al riesgo de muerte del receptor, el modelo de regresión de Cox mostró un cociente de riesgo (HR, hazard ratio) de 5.66 en los pacientes con cultivo bacteriano positivo y de 2.22 en aquellos con cepas productoras de betalactamasas de espectro extendido (BLEE); en cuanto a la pérdida del injerto, el HR fue de 4.59 en quienes tuvieron cultivo bacteriano positivo y de 4.25 en aquellos con cepas productoras de BLEE. CONCLUSIONES: Se encontró riesgo significativo de muerte en receptores de trasplante renal con cultivo bacteriano positivo y mayor riesgo de pérdida del injerto en aquellos con cultivo bacteriano positivo y aislamiento de cepas productoras de BLEE. La tasa de enterobacterias productoras de BLEE es alta, por ello son necesarias estrategias más estrictas para controlar del uso de antibióticos.

Efecto del extracto hexánico de Tagetes lucida sobre la inhibición del crecimiento de enterobacterias Shigella flexneri y Salmonella typhi / Effect of the hexanic extract of Tagetes lucida on the inhibition of the growth of enterobacteria Shigella flexneri and Salmonella typhi

La resistencia a los antibióticos aumenta la búsqueda de nuevas estrategias para combatir las enfermedades que causan, y el uso de plantas medicinales representa una estrategia altamente efectiva y valiosa, como el uso de Tagetes lucida con diferentes bacterias gram positivas y gram negativas.Objetivo: Evaluar la actividad biológica que tiene el extracto hexanico de la planta Tagetes lucida a diferentes concentraciones sobre la inhibición del crecimiento en placa y tubo de dos enterobacterias, Shigella flexneri y Salmonella typhiMétodos: En el siguiente trabajo, se evaluó un extracto de hexano de Tagetes lucida sobre la inhibición del crecimiento de dos enterobacterias, Shigella flexneri y Salmonella typhi utilizando diferentes concentraciones de vehículo para evaluar si afectaba el crecimiento bacteriano y también diferentes concentraciones de extracto para evaluar la actividad.Resultados: Realizados los estudios por triplicado se logró concretar que a partir de 75µl/µg de extracto se logra una inhibición casi total del crecimiento de ambas bacterias, tanto en método de placa, como en método de tubo. Y a partir de 100 µl/µg se logra una inhibición total.Conclusiones: Los resultados favorables obtenidos con 75 µl/µg, permiten confirmar que los extractos de plantas medicinales son una estrategia importante para combatir infecciones bacterianas multi-resistentes. Por otro lado permite dar paso a un estudio para evaluar los metabolitos más activos del extracto, así como, el mecanismo de acción sobre la inhibición del crecimiento de las bacterias en estudio. (AU)

Antibiotic resistance increases the search for new strategies to combat the diseases they cause, and the use of medicinal plants represents a highly effective and valuable strategy, such as the use of Tagetes lucida with different gram positive and gram negative bacteria.Objective: To evaluate the biological activity of the hexane extract of the Tagetes lucida plant at different concentrations on the inhibition of growth in plaque and tube of two enterobacteriaceae, Shigella flexneri and Salmonella typhiMethods: In the following work, a hexane extract from Tagetes lucida was evaluated on the growth inhibition of two enterobacteriaceae, Shigella flexneri and Salmonella typhi using different concentrations of vehicle to evaluate if it affected bacterial growth and also different concentrations of extract to evaluate activity.Results: Once the studies were carried out in triplicate, it was possible to specify that from 75µl/µg of extract, almost total inhibition of the growth of both bacteria was achieved, both in the plate method and in the tube method. And from 100 µl/µg total inhibition is achieved.Conclusions: The favorable results obtained with 75 µl/ µg, confirm that medicinal plant extracts are an important strategy to combat multi-drug resistant bacterial infections. On the other hand, it allows a study to be carried out to evaluate the most active metabolites of the extract, as well as the mechanism of action on the inhibition of the growth of the bacteria under study. (AU)

Impacto de infecciones y enterobacterias productoras de betalactamasa de espectro extendido en la supervivencia del injerto y del paciente en un programa de trasplante renal en México / Impact of infections and extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae on graft and patient survival in a kidney transplantation program in Mexico

Resumen Introducción: Los tratamientos inmunosupresores han mejorado las tasas de supervivencia del injerto y del paciente, pero pueden incrementar las infecciones postrasplante. Objetivos: Analizar los datos de pacientes con trasplante renal y describir las bacterias responsables de las infecciones que presentan. Métodos: Estudio observacional, longitudinal y analítico de 103 pacientes sometidos a trasplante renal. El periodo de seguimiento fue de 5.07 ± 1.28 años. Resultados: La tasa de mortalidad fue de 10.68 % y la de pérdida del injerto de 14.56 %. Respecto al riesgo de muerte del receptor, el modelo de regresión de Cox mostró un cociente de riesgo (HR, hazard ratio) de 5.66 en los pacientes con cultivo bacteriano positivo y de 2.22 en aquellos con cepas productoras de betalactamasas de espectro extendido (BLEE); en cuanto a la pérdida del injerto, el HR fue de 4.59 en quienes tuvieron cultivo bacteriano positivo y de 4.25 en aquellos con cepas productoras de BLEE. Conclusiones: Se encontró riesgo significativo de muerte en receptores de trasplante renal con cultivo bacteriano positivo y mayor riesgo de pérdida del injerto en aquellos con cultivo bacteriano positivo y aislamiento de cepas productoras de BLEE. La tasa de enterobacterias productoras de BLEE es alta, por ello son necesarias estrategias más estrictas para controlar del uso de antibióticos.

Abstract Introduction: Immunosuppressive treatments have improved graft and patient survival rates, but can increase the incidence of post-transplant infections. Objectives: To analyze data from kidney transplant patients and describe the pathogens responsible for the infections they experience. Methods: Longitudinal, analytical, observational study of 103 patients who underwent kidney transplantation. The follow-up period was 5.07 ± 1.28 years. Results: Overall mortality rate was 10.68% and graft loss rate was 14.56%. Regarding recipient risk of death, the Cox regression model showed a hazard ratio (HR) of 5.66 for positive bacterial cultures and 2.22 for positive extended-spectrum beta-lactamase (ESBL)-producing strains; as for graft loss, HR was 4.59 in those with positive bacterial cultures and 4.25 in those who were positive for ESBL-producing strains Conclusions: Significant death risk was found in kidney transplant recipients with positive bacterial cultures and an increased risk of graft loss in those with positive bacterial cultures and in those who were positive for ESBL-producing Enterobacteriaceae isolates. The rate of ESBL-producing Enterobacteriaceae is high, and stricter strategies are therefore necessary to control the use of antibiotics.

Mecanismos de resistencia en bacterias gramnegativas / Resistance mechanisms in Gram-negative bacteria

Los Enterobacterales resistentes a carbapenémicos o productores de betalactamasas de espectro extendido (BLEE) y los no fermentadores resistentes a carbapenémicos presentan resistencia a muchos de los antimicrobianos comúnmente empleados en la práctica clínica, y han sido reconocidos por la Organización Mundial de la Salud como una prioridad crítica para el desarrollo de nuevos antimicrobianos. En esta revisión se abordarán los principales mecanismos de resistencia de los Enterobacterales, Pseudomonas aeruginosa, Acinetobacter baumannii y Stenotrophomonas maltophilia a betalactámicos, quinolonas, aminoglucósidos y polimixinas. Se presentará información actualizada sobre la importancia en la resistencia de mecanismos de modificación de antimicrobianos (incluyendo betalactamasas de claseC de espectro extendido, carbapenemasas y enzimas modificadoras de aminoglucósidos), alteraciones de la permeabilidad por trastornos en la expresión de porinas o del lipopolisacárido, producción de bombas de expulsión activa, alteraciones de la diana o protección de la misma y expresión de sistemas de doble componente (AU)

Enterobacterales resistant to carbapenems or producing extended-spectrum β-lactamases (ESBL) and non-fermenters resistant to carbapenems present resistance to many of the antimicrobials commonly used in clinical practice, and have been recognized by the World Health Organization as a critical priority for the development of new antimicrobials. In this review, the main mechanisms of resistance of Enterobacterales, Pseudomonas aeruginosa, Acinetobacter baumannii and Stenotrophomonas maltophilia to β-lactams, quinolones, aminoglycosides and polymyxins will be addressed. Updated information will be presented on the importance in resistance of antimicrobial modification mechanisms (including classC or extended-spectrum β-lactamases, carbapenemases and aminoglycoside-modifying enzymes), permeability alterations due to porin or lipopolysaccharide expression disorders, production of active efflux pumps, target alterations or protection, and expression of two-component systems (AU)

Resistance mechanisms in Gram-negative bacteria.

Enterobacterales resistant to carbapenems or producing extended-spectrum ß-lactamases (ESBL) and non-fermenters resistant to carbapenems present resistance to many of the antimicrobials commonly used in clinical practice, and have been recognized by the World Health Organization as a critical priority for the development of new antimicrobials. In this review, the main mechanisms of resistance of Enterobacterales, Pseudomonas aeruginosa, Acinetobacter baumannii and Stenotrophomonas maltophilia to ß-lactams, quinolones, aminoglycosides and polymyxins will be addressed. Updated information will be presented on the importance in resistance of antimicrobial modification mechanisms (including class C or extended-spectrum ß-lactamases, carbapenemases and aminoglycoside-modifying enzymes), permeability alterations due to porin or lipopolysaccharide expression disorders, production of active efflux pumps, target alterations or protection, and expression of two-component systems.

Rising incidence of carbapenem resistant isolates: an Argentinian hospital's experience. More trouble in the aftermath of the COVID-19 pandemic / Incidencia creciente de aislamientos resistentes a carbapenémicos: la experiencia de un hospital argentino. Más problemas tras la pandemia de COVID-1

Introduction: During COVID-19 outbreaks, disproportionate use of antibiotics, high Intensive Care Units burden and longer in-hospital stays may have aggravated the emergency posed by carbapenem-resistant isolates. Therefore, we set out to determine whether the incidence of carbapenem-resistant isolates rose in a tertiary care center in Santa Fe, Argentina during the period with active cases of COVID-19. Material and methods: In this retrospectively designed analytic epidemiologic study, two periods were defined: Period 1 (without active cases of COVID-19) from September 2019 to August 2020 and Period 2 (starting at the onset of the first wave of COVID-19 in this Institution) from September 2020 to June 2021. All clinically relevant microbiological samples taken during these periods in the Internal Medicine, Surgical and Intensive Care Unit wards were included. The primary analysis of interest was the differential incidence between the two periods, overall and in the Intensive Care Units wards in particular. Results: 9,135 hospitalizations, 50,145 patient-days of analysis. 7,285 clinical samples were taken, with an overall positivity for carbapenem-resistant isolates of 12.1% (n=883). Overall carbapenem-resistant isolates incidence during Period 2 was 2.5 times higher than in Period 1 (2.52 vs 0.955/100 patient-days, p<0.001). Intensive Care Units' carbapenem-resistant isolates incidence raised from 6.78 to 8.69/100 patient-days in Period 2 (p=0.006). Conclusions: We found alarming rates of carbapenem-resistant isolates in our center, 2.5 times higher in the period following the first wave of COVID-19. This rise was due to a higher amount of clinically relevant microbiological samples taken and to a higher carbapenem resistance among Enterobacteria and non-fermentative Gram-negative bacilli. To our knowledge, this is one of the few Latin-American reports on the effect of the COVID-19 pandemic on carbapenem-resistant isolates incidence (AU)

Introducción: Durante los brotes de COVID-19, el uso desproporcionado de antibióticos, la alta carga de las Unidades de Cuidados Intensivos y las estancias hospitalarias más prolongadas pueden haber agravado la emergencia planteada por los aislados resistentes a carbapenémicos. Por lo tanto, nos propusimos determinar si la incidencia de aislamientos resistentes a carbapenémicos aumentó en un centro de tercer nivel de atención en Santa Fe, Argentina, durante el período con casos activos de COVID-19. Material y métodos: En este estudio epidemiológico analítico de diseño retrospectivo se definieron dos periodos: Periodo 1 (sin casos activos de COVID-19) de septiembre de 2019 a agosto de 2020, y Periodo 2 (a partir del inicio de la primera ola de COVID-19. en esta Institución) desde septiembre de 2020 hasta junio de 2021. Se incluyeron todas las muestras microbiológicas clínicamente relevantes tomadas durante estos períodos en las salas de Medicina Interna, Quirúrgica y Unidad de Cuidados Intensivos. El principal análisis de interés fue la incidencia diferencial entre los dos períodos, en general y en las salas de las Unidades de Cuidados Intensivos en particular. Resultados: 9.135 hospitalizaciones, 50.145 pacientes-día de análisis. Se tomaron 7.285 muestras clínicas, con una positividad global para aislados resistentes a carbapenémicos del 12,1% (n=883). La incidencia general de aislamientos resistentes a carbapenémicos durante el Período 2 fue 2,5 veces mayor que en el Período 1 (2,52 frente a 0,955/100 pacientes-día, p<0,001). La incidencia de aislamientos resistentes a carbapenémicos en Unidades de Cuidados Intensivos aumentó de 6,78 a 8,69/100 pacientes-día en el Período 2 (p=0,006). Conclusiones: Encontramos tasas alarmantes de aislamientos resistentes a carbapenémicos en nuestro centro, 2,5 veces mayores en el período posterior a la primera ola de COVID-19 (AU)

Antibacterial potential of essential oils against planktonic and sessile cells of Escherichia coli isolated from diarrhea cases in swine / Potencial antibacteriano de aceites esenciales contra células de Escherichia coli planctónicas y sésiles aisladas de diarrea porcina

Escherichia coli is a pathogen associated with infections in piglets in the post-weaning phase, its pathogenicity is related to the animal's susceptibility to bacterial enterotoxins. The objective of the present study was to determine the EOs activity against E. colistrain, in the form planktonic and sessile. Although the Disc-Diffusion tests to determine the Minimum Inhibitory Concentration, do not fully corroborate with the other analyzes of this study, it was noticed bacteria inhibition. The EOs were prepared at 0.4%, 0.8% and 1.0% for tests. The tested EOs were effective against E. coliplanktonic cells (p<0.05). As for the sessile cells, the most significant result was inhibition and 100% sessile cells at the concentration of 1.0% of Cymbopogon citratusEO. Although there was resistance in some treatments, the tested EOs demonstrated inhibition capacity, constituting promising alternatives for the control of E. coli, especially of planktonic cells.

Escherichia coli es un patógeno asociado con infecciones en lechones en la fase posterior al destete, su patogenicidad está relacionada con la susceptibilidad del animal a las enterotoxinas bacterianas. El objetivo del presente estudio fue determinar la actividad de contra E. coli, en la forma planctónico y sésil. Aunque las pruebas de difusión de disco para determinar la concentración inhibitoria mínima, no corroboran completamente con los otros análisis de este estudio, se observó inhibición de la bacteria. Las soluciones basadas en AE se prepararon al 0.4%, 0.8% y 1.0% para pruebas. Los AEs probados fueron efectivos contra las células planctónicas (p<0.05). En cuanto a las células sésiles, el resultado más significativo fue la inhibición y el 100% de las células sésiles a la concentración de 1,0% de Cymbopogon citratus. Aunque hubo resistencia en algunos tratamientos, los AEs probados demostraron capacidad de inhibición, constituyendo alternativas prometedoras para el control de E. coli, especialmente de células planctónicas.

Impact of sink removal from intensive care unit rooms on the consumption of antibiotics and on results of Zero Resistance Project.

INTRODUCTION: Due to the favourable impact of removing the sinks on isolations in bronchoaspirate samples of patients with mechanical ventilation, we now evaluate the impact on the consumption of antibiotics as well as on the results of the Zero Resistance Project (ZRP). PATIENTS AND METHODS: All the patients admitted to the unit in a quasi-experimental before-after study with a pre-intervention period between 2014 and 2016 and a post-intervention period from 2016 to 2017, to evaluate antibiotic consumption in defined daily doses, and until 2018, to evaluate the ZRP indicators. The intervention was the removal of the sinks from the rooms of the ICU. We evaluated antibiotic consumption densities and their ratios, grouped as Enterobacteriaceae and non-fermenting gram-negative bacilli (NFGNB) according to their antibiograms; the absolute number of 'antibiotic days', 'hospitalised days', 'isolation days', and 'multi-resistant bacteria (MRB) days'; as well as their incidence densities per 1000 hospitalised days and the ratio between the two years prior to and the two years after the intervention. RESULTS: Post-intervention antibiotic use was 1.61-fold (1.60-1.62) and 2.24-fold (2.10-2.37) lower for antibiotics used against Enterobacteriaceae and NFGNB, respectively. There were also reductions in the number of days of antibiotic use by 1.29-fold (1.22-1.36), number of MRB days by 1.84-fold (1.63-2.08), and number of patient isolation days by 1.51-fold (1.38-1.66). DISCUSSION: The results suggest that the intervention had a favourable impact on the consumption of antibiotics, as well as on the number of days on antibiotics, MRB, and isolation.

Use of MALDI-TOF for identification and surveillance of gram-negative bacteria in captive wild psittacines / Uso do MALDI-TOF para identificação e monitoramento de bactérias Gram-negativas em psitacídeos cativos

Microbiological studies of the sanitary and health status of psittacine birds that will be reintroduced is important in evaluating whether these animals act as carriers of pathogenic agents to other animals and humans. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a faster and more accurate method to identify bacteria than conventional microbiology methods. The aim of this study was to evaluate the health status of psittacines housed in captivity, by assessment of Gram-negative bacteria from fecal microbiota through MALDI- TOF MS identification. The results indicate high frequency of Gram-negative bacteria in feces (96.5%), especially from the Enterobacteriaceae family (88.7%). The most prevalent bacteria were Escherichia coli (39.0%), Proteus vulgaris (12.2%), Klebsiella spp. (12.1%) and Raoultella ornithinolytica (8.7%). Proteus hauseri, Citrobacter spp., Morganella morgannii, Providencia rettgeri, Enterobacter spp. and Escherichia hermannii were isolated with lower frequency. . All these agents are potentially pathogenic for parrots and can cause systemic infections in other animals and humans. These findings reinforce that MALDI- TOF MS proved to be a rapid and accurate method of identification of the microorganism and evaluation of the health status of psittacines, providing relevant data to assist decision-making regarding the sanitary protocols in wildlife centers, and possible future reintroduction of wild birds.

Estudos microbiológicos da sanidade de psitacídeos que serão reintroduzidos são importantes para avaliar se esses animais atuam como portadores de agentes patogênicos para outros animais e humanos. A espectrometria de massa por ionização/dessorção de matriz assistida por laser/tempo de vôo (MALDI-TOF MS) é um método mais rápido e preciso para identificar bactérias na comparação com métodos convencionais de microbiologia. O objetivo deste estudo foi avaliar o estado de saúde de psitacídeos cativos, identificando bactérias Gram-negativas da microbiota fecal por MALDI -TOF MS. Os resultados indicaram alta frequência de bactérias Gram-negativas nas fezes (96,5%), principalmente da família Enterobacteriaceae (88,7%). As mais prevalentes foram Escherichia coli (39,0%), Proteus vulgaris (12,2%), Klebsiella spp. (12,1%) e Raoultella ornithinolytica (8,7%). Proteus hauseri, Citrobacter spp., Morganella morgannii, Providencia rettgeri, Enterobacter spp. e Escherichia hermannii foram isolados com menor frequência. Todos esses agentes são potencialmente patogênicos para os papagaios e podem causar infecções sistêmicas em outros animais e seres humanos. Esses achados reforçam que o MALDI- TOF MS é um método rápido e preciso de identificação do microrganismo e avaliação do estado de saúde dos psitacídeos, fornecendo dados relevantes para auxiliar na tomada de decisões sobre os protocolos sanitários em centros de triagem de animais selvagens e sobre a possibilidade de reintrodução futura.

Use of MALDI-TOF for identification and surveillance of gramnegative bacteria in captive wild psittacines / Uso do MALDI-TOF para identificação e monitoramento de bactérias Gram negativas em psitacídeos cativos

Microbiological studies of the sanitary and health status of psittacine birds that will be reintroduced is important in evaluating whether these animals act as carriers of pathogenic agents to other animals and humans. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a faster and more accurate method to identify bacteria than conventional microbiology methods. The aim of this study was to evaluate the health status of psittacines housed in captivity, by assessment of Gram-negative bacteria from fecal microbiota through MALDI- TOF MS identification. The results indicate high frequency of Gram-negative bacteria in feces (96.5%), especially from the Enterobacteriaceae family (88.7%). The most prevalent bacteria were Escherichia coli (39.0%), Proteus vulgaris (12.2%), Klebsiella spp. (12.1%) and Raoultella ornithinolytica (8.7%). Proteus hauseri, Citrobacter spp., Morganella morgannii, Providencia rettgeri, Enterobacter spp. and Escherichia hermannii were isolated with lower frequency. . All these agents are potentially pathogenic for parrots and can cause systemic infections in other animals and humans. These findings reinforce that MALDI- TOF MS proved to be a rapid and accurate method of identification of the microorganism and evaluation of the health status of psittacines, providing relevant data to assist decision-making regarding the sanitary protocols in wildlife centers, and possible future reintroduction of wild birds.

Estudos microbiológicos da sanidade de psitacídeos que serão reintroduzidos são importantes para avaliar se esses animais atuam como portadores de agentes patogênicos para outros animais e humanos. A espectrometria de massa por ionização/dessorção de matriz assistida por laser/tempo de vôo (MALDI-TOF MS) é um método mais rápido e preciso para identificar bactérias na comparação com métodos convencionais de microbiologia. O objetivo deste estudo foi avaliar o estado de saúde de psitacídeos cativos, identificando bactérias Gram-negativas da microbiota fecal por MALDI -TOF MS. Os resultados indicaram alta frequência de bactérias Gram-negativas nas fezes (96,5%), principalmente da família Enterobacteriaceae (88,7%). As mais prevalentes foram Escherichia coli (39,0%), Proteus vulgaris (12,2%), Klebsiella spp. (12,1%) e Raoultella ornithinolytica (8,7%). Proteus hauseri, Citrobacter spp., Morganella morgannii, Providencia rettgeri, Enterobacter spp. e Escherichia hermannii foram isolados com menor frequência. Todos esses agentes são potencialmente patogênicos para os papagaios e podem causar infecções sistêmicas em outros animais e seres humanos. Esses achados reforçam que o MALDI- TOF MS é um método rápido e preciso de identificação do microrganismo e avaliação do estado de saúde dos psitacídeos, fornecendo dados relevantes para auxiliar na tomada de decisões sobre os protocolos sanitários em centros de triagem de animais selvagens e sobre a possibilidade de reintrodução futura.

Use of MALDI-TOF for identification and surveillance of gram-negative bacteria in captive wild psittacines

Abstract Microbiological studies of the sanitary and health status of psittacine birds that will be reintroduced is important in evaluating whether these animals act as carriers of pathogenic agents to other animals and humans. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a faster and more accurate method to identify bacteria than conventional microbiology methods. The aim of this study was to evaluate the health status of psittacines housed in captivity, by assessment of Gram-negative bacteria from fecal microbiota through MALDI- TOF MS identification. The results indicate high frequency of Gram-negative bacteria in feces (96.5%), especially from the Enterobacteriaceae family (88.7%). The most prevalent bacteria were Escherichia coli (39.0%), Proteus vulgaris (12.2%), Klebsiella spp. (12.1%) and Raoultella ornithinolytica (8.7%). Proteus hauseri, Citrobacter spp., Morganella morgannii, Providencia rettgeri, Enterobacter spp. and Escherichia hermannii were isolated with lower frequency. . All these agents are potentially pathogenic for parrots and can cause systemic infections in other animals and humans. These findings reinforce that MALDI- TOF MS proved to be a rapid and accurate method of identification of the microorganism and evaluation of the health status of psittacines, providing relevant data to assist decision-making regarding the sanitary protocols in wildlife centers, and possible future reintroduction of wild birds.

Resumo Estudos microbiológicos da sanidade de psitacídeos que serão reintroduzidos são importantes para avaliar se esses animais atuam como portadores de agentes patogênicos para outros animais e humanos. A espectrometria de massa por ionização/dessorção de matriz assistida por laser/tempo de vôo (MALDI-TOF MS) é um método mais rápido e preciso para identificar bactérias na comparação com métodos convencionais de microbiologia. O objetivo deste estudo foi avaliar o estado de saúde de psitacídeos cativos, identificando bactérias Gram-negativas da microbiota fecal por MALDI -TOF MS. Os resultados indicaram alta frequência de bactérias Gram-negativas nas fezes (96,5%), principalmente da família Enterobacteriaceae (88,7%). As mais prevalentes foram Escherichia coli (39,0%), Proteus vulgaris (12,2%), Klebsiella spp. (12,1%) e Raoultella ornithinolytica (8,7%). Proteus hauseri, Citrobacter spp., Morganella morgannii, Providencia rettgeri, Enterobacter spp. e Escherichia hermannii foram isolados com menor frequência. Todos esses agentes são potencialmente patogênicos para os papagaios e podem causar infecções sistêmicas em outros animais e seres humanos. Esses achados reforçam que o MALDI- TOF MS é um método rápido e preciso de identificação do microrganismo e avaliação do estado de saúde dos psitacídeos, fornecendo dados relevantes para auxiliar na tomada de decisões sobre os protocolos sanitários em centros de triagem de animais selvagens e sobre a possibilidade de reintrodução futura.

Caracterización clínica-microbiológica y factores de riesgo de las bacteriemias por enterobacterias productoras de betalactamasas de espectro extendido en el hospital universitario / Clinical-microbiological characterization and risk factors of bacteremia caused by extended-spectrum beta-lactamase-producing enterobacteria at the university hospital

INTRODUCCIÓN: Las infecciones del torrente sanguíneo se asocian con alta morbi- mortalidad, siendo frecuentemente causadas por enterobacterias, y cuando éstas producen ß-lactamasas de espectro extendido (BLEEs), la morbi-mortalidad, duración internación y costos sanitarios son aún mayores. OBJETIVO: Caracterizar los episodios de bacteriemia por enterobacterias en el Hospital Universitario en un período de 2 años. METODOLOGÍA: Estudio observacional, analítico, casos controles (1:1), con recolección de datos retrospectiva. Población: pacientes ≥18 años atendidos en el Hospital Universitario en período 01/01/2014 - 30/11/2015, con hemocultivo positivo por enterobacteria. Recolección datos clínicos-epidemiológicos: revisión registros médicos. Estudio microbiológico: Identificación y susceptibilidad - equipo automatizado Vitek® 2 system (bioMérieux, Marcy l'Etoile, France). Sensibilidad a fosfomicina: disco-difusión (E. coli) y dilución en agar (resto de las enterobacterias). Ceftazidime-avibactam: disco-difusión. Aislamientos BLEE+ según Vitek: confirmación y caracterización de BLEE: reacción en cadena de la polimerasa (PCR) y secuenciación. Investigación mecanismos transferibles de resistencia a quinolonas (TMQR) qnrB y aac(6')-Ib-cr: PCR. Caracterización molecular enterobacterias BLEE más prevalentes: MultiLocus Sequence Typing (MLST) y Pulsed Field Gel Electrophoresis (PFGE). Análisis casos y controles: I)Factores de riesgo bacteriemia BLEE: Casos - pacientes con bacteriemia por enterobacteria BLEE(+). Controles - pacientes con bacteriemia por enterobacteria BLEE (-) sensible a cefalosporinas tercera generación. II) Factores de riesgo mortalidad intrahospitalaria: Casos - pacientes con mortalidad hospitalaria por cualquier causa. Controles ­ pacientes egresados vivos. Análisis estadístico: paquete estadístico IBM SPSS Statistics 23. Análisis casos y controles: cálculo de odd ratios (OR) e intervalo de confianza al 95% (IC95%). Variables con p ≤0.05 en análisis univariado incluídas en análisis multivariado (regresión logística). Proyecto aprobado por Comité Ética del Hospital de Clínicas y financiado por ANII (FMV_3_2016_1_126580, Fondo María Viña ­ 2016). RESULTADOS: Principales resultados microbiológicos: 174 episodios de bacteriemia y 178 enterobacterias recuperadas, con confirmación molecular de producción BLEE en 41 enterobacterias (23%): 29 Klebsiella pneumoniae, 7 Escherichia coli, 2 Serratia marcescens, 1 Enterobacter cloacae, 1 Citrobacter freundii y 1 Morganella morganii. E. coli enterobacteria más recuperada (n=69), pero K. pneumoniae la enterobacteria BLEE más prevalente (56 aislamientos y 29/56 BLEE+), seguida de E. coli (7/69). Distribución de las enterobacterias BLEE+ según enzima detectada: CTX- M-15: 32 aislamientos, CTX-M-15 + CTX- M-14: 3 aislamientos, CTX-M-2: 3, CTX-M-8: 2, SHV-5: 1. Susceptibilidad enterobacterias BLEE: meropenem 100%, ceftazidime-avibactam 100%, fosfomicina 100%, imipenem 98%, ertapenem 97,6%, colistin 92,7%, amikacina 85,4%, gentamicina 36,6%, tigeciclina 29,3%, piperacilina-tazobactam 26,8%, trimetoprim-sulfametoxazol 19,5%, ciprofloxacina 12,2%. Detección de mecansimos transferibles de resistencia a quinolonas (TMQR) en 33/41 aislamientos (80,5%): aac(6')-Ib-cr: 22 aislamientos, qnrB: 2 aislamientos, y aac(6')-Ib-cr + qnrB: 9 aislamientos. Detección de secuenciotipos "exitosos" en principales enterobacterias BLEE: E. coli ST 73 (1), ST 95(1) y ST 38 (2) y ST 258 en K. pneumoniae (12/29=41,4%). También detección ST 258 en un aislamiento de K. pneumoniae BLEE (-). Principales resultados clínicos ­ epidemiológicos: Se revisaron 98 registros médicos; 60 bacteriemias nosocomiales, 29 comunitarias, 8 asociadas a los cuidados de la salud, 1 sin dato. 41 BLEE(+) y 57 BLEE(-). 80 pacientes vivos al egreso, 17 fallecidos y 1 sin dato. Factores de riesgo bacteriemia BLEE(+) (análisis multivariado) : presencia de dispositivo médico a permanencia previo (p 0,001, OR 55,2, IC 95%5,5-553) ) y bacteriemia no comunitaria (p 0,008 OR 17,4 IC95% 2,1-143). Factores de riesgo mortalidad intrahospitalaria (análisis multivariado): enfermedad hematooncológica o neoplásica (OR 4,687 IC95% 1,207-18,200) y score qPitt ≥2 (OR 10,332 IC95% 2,639-40,442). Antibioticoterapia empírica activa in vitro para la bacteriemia: 10/29(34,5%) en pacientes BLEE(+) y 36/40 BLEE(-) (90%). Se encontró asociación entre bacteriemia BLEE + y recibir antibioticoterapia empírica inactiva (p<0,0001) ; siendo el riesgo de recibir antibioticoterapia empírica inactiva 17 veces mayor en bacteriemias BLEE(+) respecto a BLEE(-). Se encontró que la mediana de la duración de la hospitalización a partir del episodio de bacteriemia es más prolongada en casos BLEE+ que en los controles BLEE- (22,5 versus 14 días, p=0,006). CONCLUSIONES: Enterobacteria BLEE más prevalente K. pneumoniae, y dentro de ella alta prevalencia del clon exitoso de alto riesgo ST 258. Predominio de CTX-M-15, y alta prevalencia (> 80%) de TMQR en aislamientos BLEE. Presencia de BLEE aumenta significativamente el riesgo de recibir antibioticoterapia empírica inactiva. Necesidad de mantener vigilancia de perfiles de susceptibilidad y clones circulantes y considerar posibles factores de riesgo al momento se seleccionar antibioticoterapia empírica.

BACKGROUND: Bloodstream infections are associated with high morbidity and mortality, being frequently caused by Enterobacteriaceae, and when they produce extended spectrum ß-lactamases (ESBL), morbidity, mortality and healthcare costs are even higher. OBJECTIVE: We aimed to characterize Enterobacteriaceae bacteremia episodes at the "Hospital de Clínicas", in a 2 years period. METHODS: Observational, analytical study, case-controls (1: 1), with retrospective data collection. Population: ≥18 years old patients attended at the "Hospital de Clínicas" between 01/01/2014 and 11/30/2015, with Enterobacteriaceae recovered from blood culture. Collection of clinical-epidemiological data: review of medical records. Microbiological study: identification and susceptibility: automated system Vitek® 2 (bioMérieux, Marcy l'Etoile, France). Susceptibility to fosfomycin: disc-diffusion (E. coli) and agar dilution (others Enterobacterales). Ceftazidime-avibactam: disc-diffusion. ESBL (+) isolates according to Vitek: ESBL confirmation and characterization by Polymerase Chain Reaction (PCR) and sequencing. Investigation of transferable mechanisms of quinolone resistance (TMQR) qnrB and aac (6 ')- Ib-cr: PCR. Molecular characterization of the most prevalent ESBL enterobacterales: MultiLocus Sequence Typing (MLST) and Pulsed Field Gel Electrophoresis (PFGE). Case-control analysis: I) ESBL bacteremia risk factors: Cases - patients with bacteremia by an ESBL-producing enterobacteria. Controls - patients with third generation cephalosporin susceptible enterobacteria, not ESBL-producing. II) In-hospital mortality risk factors: Cases - patients with in-hospital mortality from any cause. Controls - patients discharged alive. Statistical analysis: IBM SPSS Statistics 23 statistical package. Case-control analysis: calculation of odd ratios (OR) and 95% confidence interval (95% CI). Variables with p ≤0.05 in univariate analysis were included in multivariate analysis (logistic regression). Project approved by the Hospital de Clinicas Ethics Committee and financed by ANII (FMV_3_2016_1_126580, María Viña Fund - 2016). RESULTS: Main microbiological results: 174 bacteremia episodes and 178 enterobacterales recovered. ESBL production confirmated in 41 isolates (23%): 29 Klebsiella pneumoniae, 7 Escherichia coli, 2 Serratia marcescens, 1 Enterobacter cloacae, 1 Citrobacter freundii y 1 Morganella morganii.E. coli was the most recovered enterobacteria (n = 69), but K. pneumoniae was the most prevalent ESBL producing specie (56 isolates and 29/56 ESBL +), followed by E. coli (7/69). Distribution of ESBL producing enterobacterales according to enzyme detected: CTX- M-15: 32 isolates, CTX-M-15 + CTX-M-14: 3 isoaltes, CTX-M-2: 3, CTX-M-8: 2, SHV-5: 1. Antibiotic susceptibility in ESBL producers: meropenem 100%, ceftazidime-avibactam 100%, fosfomycin 100%, imipenem 98%, ertapenem 97,6%, colistin 92,7%, amikacin 85,4%, gentamicin 36,6%, tigecycline 29,3%, piperacillin-tazobactam 26,8%, trimethroprim sulfamethoxazole 19,5%, ciprofloxacin 12,2%. Detection of TMQR in 33/41 isolates (80.5%): aac(6')-Ib-cr: 22 isolates, qnrB: 2 isolates, and aac(6')Ib-cr + qnrb: 9 isolates. We detected "successful" sequence types within E. coli ESBL producing: ST 73 (1 isolate), ST 95 (1) and ST 38 (2) and a high prevalence of ST 258 among K. pneumoniae isolates (12/29 = 41.4%). ST 258 was also detected in one ESBL(-) K. pneumoniae isolate. Main clinical-epidemiological results: 98 medical records were reviewed; 60 bacteremia episodes were classified as nosomial, 29 as community acquired, 8 health care associated, and for one episode, data was insufficient for its classification. 41 were ESBL(+) and 57 ESBL(-). 80 patients alive at discharge, 17 deceased and 1 without data. Risk factors for ESBL bacteremia according to multivariate analysis were: use of medical device prior to hospitalization (OR = 50.226, 95% CI 4.367 - 577.721) and non-community bacteremia (OR 12.052, 95% CI 1.350-107.605). In-hospital mortality risk factors (multivariate analysis): hemato-oncological or neoplasic disease (OR 4,687 95% CI 1,207-18,200) and qPitt score ≥2 (OR 10,332 95% CI 2,639-40,442). The empirical antibiotic therapy was active according to the susceptibility test in 10/29 (34,5%) patients with ESBL (+) bacteremia and in 36/40 patients with ESBL (-) (90%). Presence of ESBL was found to be associated with inactive empirical antibiotic therapy (p<0.0001), and risk for receiving inactive empirical antibiotic therapy was 17 times higher in ESBL (+) compared to ESBL (-). The mean length of hospital stay after the onset of bacteraemia was longer in the cases of ESBL producers than in the cases of non-ESBL producers ( 22,5 vs. 14 days; P=0.006). CONCLUSIONS: K. pneumoniae was the most prevalent ESBL producing specie, and within it we found a high prevalence of the successful high-risk clone ST258. CTX-M-15 was the main ESBL detected and we found high prevalence (80%) of TMQR among ESBL(+). Presence of ESBL significantly increases the risk of receiving inactive empirical antibiotic therapy. Need to maintain surveillance of susceptibility profiles and circulating clones and to take into account possible risk factors when selecting empirical antibiotic therapy.

Implementation of contact isolation strategy for the containment of extended-spectrum ß-lactamase carriers in a University Hospital positively affects the epidemiology of carbapenemase-producing Enterobacterales.

INTRODUCTION: The lack of consensus of control measures to prevent extended-spectrum ß-lactamase producing Enterobacterales (ESBL-E) transmission in the hospital setting is of great concern. We describe the prevalence and species distribution of ESBL-E and carbapenemase producing Enterobacterales (CPE) in patients admitted in a tertiary Hospital during an active surveillance screening program for detecting ESBL-E carriers and reducing the ESBL-E transmission (R-GNOSIS Project). METHODS: From March-2014 to March-2016, 15,556 rectal swabs were collected from 8209 patients admitted in two medical (Gastroenterology, Pneumology) and two surgical (Neurosurgery, Urology) wards. Swabs were seeded onto ChromoID-ESBL and -CARB/OXA-48 agar plates. Growing colonies were identified by MALDI-TOF MS. ESBL and carbapenemases were phenotypically detected. Changes in species diversity (SDI) and distribution over time were analyzed. RESULTS: ESBL-E incidence (8.4%) tended to decrease over time (p=0.003) and CPE carrier prevalence remained unchanged during the study (2%). The contact isolation strategy targeted to reduce ESBL-E transmission was ineffective in reducing ESBL-E carriers but significant differences were observed with CPE (p=0.017). SDI did not change among ESBL-E and E. coli was predominant (78.5%) during the study. K. pneumoniae (54%) was the most frequent CPE species, followed by E. coli (19%). SDI decreased among the CPE population over time mainly due to K. pneumoniae dominance and increased E. coli prevalence in the last part of the study. CONCLUSIONS: During the R-GNOSIS project, contact precautions were not effective in reducing the ESBL-E transmission but may have had a positive collateral effect on the CPE containment.

Implementation of contact isolation strategy for the containment of extended - spectrum beta lactamase carriers in a University Hospital positively affects the epidemiology of carbapenemase-producing Enterobacterales / La implementación de la estrategia de aislamiento de contacto para la contención de portadores de beta lactamasas de espectro extendido en un hospital universitario afecta positivamente a la epidemiología de las enterobacterias productoras de carbapenemasas

Introduction: The lack of consensus of control measures to prevent extended-spectrum β-lactamase producing Enterobacterales (ESBL-E) transmission in the hospital setting is of great concern. We describe the prevalence and species distribution of ESBL-E and carbapenemase producing Enterobacterales (CPE) in patients admitted in a tertiary Hospital during an active surveillance screening program for detecting ESBL-E carriers and reducing the ESBL-E transmission (R-GNOSIS Project). Methods: From March-2014 to March-2016, 15,556 rectal swabs were collected from 8209 patients admitted in two medical (Gastroenterology, Pneumology) and two surgical (Neurosurgery, Urology) wards. Swabs were seeded onto ChromoID-ESBL and -CARB/OXA-48 agar plates. Growing colonies were identified by MALDI-TOF MS. ESBL and carbapenemases were phenotypically detected. Changes in species diversity (SDI) and distribution over time were analyzed. Results: ESBL-E incidence (8.4%) tended to decrease over time (p=0.003) and CPE carrier prevalence remained unchanged during the study (2%). The contact isolation strategy targeted to reduce ESBL-E transmission was ineffective in reducing ESBL-E carriers but significant differences were observed with CPE (p=0.017). SDI did not change among ESBL-E and E. coli was predominant (78.5%) during the study. K. pneumoniae (54%) was the most frequent CPE species, followed by E. coli (19%). SDI decreased among the CPE population over time mainly due to K. pneumoniae dominance and increased E. coli prevalence in the last part of the study. Conclusions: During the R-GNOSIS project, contact precautions were not effective in reducing the ESBL-E transmission but may have had a positive collateral effect on the CPE containment.(AU)

Introducción: La falta de consenso en las medidas de control necesarias para prevenir la transmisión de enterobacterias productoras de β-lactamasas de espectro extendido (BLEE-E) en el entorno hospitalario es muy preocupante. En este trabajo describimos la prevalencia y la distribución de especies de BLEE-E y las enterobacterias productoras de carbapenemasas (EPC) en pacientes ingresados en un hospital terciario durante un programa de vigilancia activa para detectar portadores de BLEE-E y reducir su transmisión (Proyecto R-GNOSIS). Métodos: Entre marzo-2014 y marzo-2016 se recogieron 15.556 hisopos rectales de 8.209 pacientes ingresados en 2 servicios médicos (Gastroenterología, Neumología) y 2 quirúrgicos (Neurocirugía, Urología). Los hisopos se sembraron en las placas de agar ChromoID-ESBL y CARB/OXA-48. Las colonias crecidas fueron identificadas por MALDI-TOF MS. La producción de BLEE y carbapenemasas se confirmó fenotípicamente. Se analizaron los cambios en la diversidad de especies (SDI) y su distribución en el tiempo. Resultados: La incidencia de BLEE-E (8,4%) tendió a disminuir (p=0,003) y la prevalencia de portadores de CPE permaneció sin cambios durante el estudio (2%). La estrategia de aislamiento de contacto dirigida a reducir la transmisión de BLEE-E fue ineficaz, pero se observaron diferencias significativas en las EPC (p=0,017). La SDI de las BLEE-E no cambió durante el estudio y E. coli fue la especie predominante (78,5%). K. pneumoniae (54%) fue la especie de EPC más frecuente, seguida de E. coli (19%). El SDI disminuyó entre la población de EPC, principalmente debido al dominio de K. pneumoniae y al aumento de la prevalencia de E. coli en la última parte del estudio. Conclusiones: Durante el proyecto R-GNOSIS, las precauciones de contacto no fueron efectivas para reducir la transmisión de BLEE-E, pero pudo haber tenido un efecto colateral positivo en la contención de EPC.(AU)

Prevalencia de infección del tracto urinario y perfil de susceptibilidad antimicrobiana en Enterobacterias

Resumen Las Infecciones del Tracto Urinario (ITU), constituyen uno de los principales motivos de consulta en el ámbito de atención primaria, debido al aumento de la resistencia antibacteriana. Objetivo . Caracterizar la prevalencia de infección del tracto urinario y el perfil de susceptibilidad antimicrobiana in vitro en Enterobacterias en los pacientes de la provincia de Santa Elena - Ecuador. Método . Esta investigación fue descriptiva de diseño documental. La población fue de 827 registros de urocultivos, recopilados de la base de datos del laboratorio de microbiología del Centro de Especialidades IESS La Libertad, en el período comprendido desde agosto 2019 hasta marzo de 2020. Los datos fueron procesados mediante estadística descriptiva, análisis de frecuencia y chi cuadrado. Resultados . De este estudio indican que la prevalencia de ITU fue 22,1%; los principales agentes etiológicos fueron: E. coli (76,0%), Klebsiella oxytoca (6,5%), Klebsiella pneumoniae (5,8%) y Proteus mirabilis (3,9%). La ITU y la infección por E. coli fueron estadísticamente mayores en mujeres y adultos mayores. La mayor frecuencia de resistencia de E. coli fue para ácido nalidíxico (81,2%), ampicilina (79,9%), ciprofloxacina (72,6%) y sulfametoxazol trimetoprima (61,5%); en Klebsiella oxytoca fue ampicilina (80,0%), sulfametoxazol trimetoprima (70,0%), ácido nalidíxico (60,0%) y ciprofloxacina (40,0%). Mientras que en Klebsiella pneumoniae se halló una resistencia del (100%) para ampicilina y cefalotina, amoxicilina y ácido clavulánico (66,7%), ciprofloxacina (55,6%), ácido nalidíxico (44,4%), meropenem e imipenem (11,1%). Conclusiones. La E. coli continúa siendo el microorganismo más frecuente en ITU. El tratamiento empírico de ITU debería incluir amikacina, nitrofurantoina y piperacilina tazobactam.

Abstract Urinary Tract Infections (UTI) are one of the main reasons for consultation in the primary care setting, due to the increase in antibacterial resistance. Objective . To characterize the prevalence of urinary tract infection and the in vitro antimicrobial susceptibility profile of Enterobacteriaceae in patients in the province of Santa Elena - Ecuador. Method. This was a descriptive research of documentary design. The population was 827 urine culture records, collected from the database of the microbiology laboratory of the Centro de Especialidades IESS La Libertad, in the period from August 2019 to March 2020. The data were processed using descriptive statistics, frequency analysis and chi-square. Results . From this study indicate that the prevalence of UTI was 22.1%; the main etiological agents were: E. coli (76.0%), Klebsiella oxytoca (6.5%), Klebsiella pneumoniae (5.8%) and Proteus mirabilis (3.9%). UTI and E. coli infection were statistically higher in women and older adults. The highest frequency of E. coli resistance was for nalidixic acid (81.2%), ampicillin (79.9%), ciprofloxacin (72.6%) and trimethoprim sulfamethoxazole (61.5%); in Klebsiella oxytoca it was ampicillin (80.0%), trimethoprim sulfamethoxazole (70.0%), nalidixic acid (60.0%) and ciprofloxacin (40.0%). While in Klebsiella pneumoniae, 100% resistance was found for ampicillin and cephalothin, amoxicillin and clavulanic acid (66.7%), ciprofloxacin (55.6%), nalidixic acid (44.4%), meropenem and imipenem (11.1%). Conclusions . E. coli continues to be the most frequent microorganism in UTI. Empirical treatment of UTI should include amikacin, nitrofurantoin and piperacillin tazobactam.

Resumo As infecções do trato urinário (IU) são um dos principais motivos de consulta no âmbito dos cuidados primários, devido ao aumento da resistência antibacteriana. Objetivo . Caracterizar a prevalência da infecção do trato urinário e o perfil de suscetibilidade antimicrobiana in vitro de Enterobacteriaceae em pacientes da província de Santa Elena - Equador. Método . Esta foi uma pesquisa descritiva do projeto documental. A população era de 827 registros de cultura de urina, coletados do banco de dados do laboratório de microbiologia do Centro de Especialidades IESS La Libertad, no período de agosto de 2019 a março de 2020. Os dados foram processados utilizando estatísticas descritivas, análise de freqüência e qui-quadrado. Resultados. Deste estudo indicam que a prevalência de UTI foi de 22,1%; os principais agentes etiológicos foram: E. coli (76,0%), Klebsiella oxytoca (6,5%), Klebsiella pneumoniae (5,8%) e Proteus mirabilis (3,9%). A infecção por UTI e E. coli foi estatisticamente maior nas mulheres e nos adultos mais velhos. A maior freqüência de resistência do E. coli foi para o ácido nalidíxico (81,2%), ampicilina (79,9%), ciprofloxacina (72,6%) e trimetoprim sulfametoxazol (61,5%); em Klebsiella oxytoca era ampicilina (80,0%), trimetoprim sulfametoxazol (70,0%), ácido nalidíxico (60,0%) e ciprofloxacina (40,0%). Enquanto em Klebsiella pneumoniae, foi encontrada 100% de resistência para ampicilina e cefalotina, amoxicilina e ácido clavulânico (66,7%), ciprofloxacina (55,6%), ácido nalidíxico (44,4%), meropenem e imipenem (11,1%). Conclusões . A E. coli continua sendo o microorganismo mais freqüente na UTI. O tratamento empírico da UTI deve incluir amikacina, nitrofurantoína e piperacilina tazobactam.