Microbiological etiology and current resistance patterns in acute calculous cholecystitis.

INTRODUCTION: The current treatment for acute calculous cholecystitis (ACC) is early laparoscopic cholecystectomy, in association with appropriate empiric antibiotic therapy. In our country, the evolution of the prevalence of the germs involved and their resistance patterns have been scarcely described. The aim of the study was to analyze the bacterial etiology and the antibiotic resistance patterns in ACC. METHODS: We conducted a single-center, retrospective, observational study of consecutive patients diagnosed with ACC between 01/2012 and 09/2019. Patients with a concomitant diagnosis of pancreatitis, cholangitis, postoperative cholecystitis, histology of chronic cholecystitis or carcinoma were excluded. Demographic, clinical, therapeutic and microbiological variables were collected, including preoperative blood cultures, bile and peritoneal fluid cultures. RESULTS: A total of 1104 ACC were identified, and samples were taken from 830 patients: bile in 89%, peritoneal fluid and/or blood cultures in 25%. Half of the bile cultures and less than one-third of the blood and/or peritoneum samples were positive. Escherichia coli (36%), Enterococcus spp (25%), Klebsiella spp (21%), Streptococcus spp (17%), Enterobacter spp (14%) and Citrobacter spp (7%) were isolated. Anaerobes were identified in 7% of patients and Candida spp in 1%. Nearly 37% of patients received inadequate empirical antibiotic therapy. Resistance patterns were scrutinized for each bacterial species. The main causes of inappropriateness were extended-spectrum beta-lactamase-producing bacteria (34%) and Enterococcus spp (45%), especially in patients older than 80 years. CONCLUSIONS: Updated knowledge of microbiology and resistance patterns in our setting is essential to readjust empirical antibiotic therapy and ACC treatment protocols.

Implementación de un programa para mitigar la resistencia a los antimicrobianos en escenarios de bajos recursos / Implementation of a program to face antimicrobial resistance on a low resources hospital

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

Criterios de aislamiento preventivo para la detección de portadores de bacterias multirresistentes en pacientes ingresados en la UCI: estudio multicéntrico dentro del programa Resistencia Zero / Preventive isolation criteria for multidrug-resistant bacteria detection in patients admitted to the ICU: Multicenter study within the Zero Resistance program

Objetivo: Conocer el rendimiento de los criterios de aislamiento preventivo del programa Resistencia Zero (RZ) e identificar los factores que pudieran mejorar su rendimiento. Diseño: Estudio de cohorte prospectivo y multicéntrico. Ámbito: Unidades de cuidados críticos que aplicaban el protocolo RZ, y que aceptaron la invitación al estudio. Pacientes o participantes: Pacientes a los que se les realizaron cultivos de vigilancia (nasal, faríngeo, axilar y rectal) y/o diagnósticos al ingreso en la UCI. Intervenciones: Análisis de los factores de riesgo (FR) RZ y otras variables del registro ENVIN. Se realizó un estudio univariable y multivariable con metodología de regresión logística binaria (significación con p<0,05). Se efectuó análisis de sensibilidad y especificidad para cada uno de los factores seleccionados. Variables de interés principales: Portador de bacteria multirresistente (BMR) al ingreso en la UCI, FR (antecedente de colonización/infección por BMR, ingreso hospitalario en los 3 meses previos, uso de antibiótico el mes previo, estar institucionalizado, diálisis y otras condiciones crónicas) y comorbilidades. Resultados: Participaron 2.252 pacientes de 9 UCI españolas. Fueron identificados BMR en 283 (12,6%). Ciento noventa y tres (68,2%) presentaban algún FR (OR: 4,6; IC 95%: 3,5-6,0). Todos los FR del programa RZ alcanzaron significación estadística (sensibilidad: 66%; especificidad: 79%), siendo el antecedente de BMR el factor con más peso. Inmunodepresión, tratamiento antibiótico al ingreso y sexo masculino son FR adicionales para BMR. Se aislaron BMR en 87 (31,8%) sin FR. (AU)

Objective: To verify the validity of a check list of risk factors (RF) proposed by the Spanish “Resistencia Zero” project (RZ) in the detection of multi-resistant bacteria (MRB), as well as to identify other possible RF for colonization and infection by MRB at intensive care (ICU) admission. Design: A prospective cohort study, conducted in 2016. Setting: Multicenter study, patients who needed admission to adult critical care units that applied the RZ protocol and accepted the invitation for the study. Patients or participants: Consecutive sample of patients admitted to ICU, who underwent surveillance (nasal, pharyngeal, axillary, and rectal) or clinical cultures. Interventions: Analysis of the RF of RZ project, in addition to other comorbidities, included in the ENVIN registry. A univariate and multivariate study was conducted, with binary logistic regression methodology (significance with P<.05). Sensitivity and specificity analyses were performed for each of the selected factors. Main variables of interest: Carrier of BMR at ICU admission, RF (previous MRB colonization/infection, hospital admission in the previous 3 months, antibiotic use in the past month, institutionalization, dialysis, and other chronic conditions) and comorbidities. Results: Two thousand two hundred and seventy patients were included from 9 Spanish ICUs. We identified BMR in 288 (12.6% of total patients admitted). One hundred and ninety-three (68.2%) had some RF (OD 4.6 -95% CI 3.5-6.0). All 6 RF from check list achieved statistical significance in the univariate analysis (sensitivity 66%, specificity 79%). Immunosuppression, antibiotic use at ICU admission and male gender were additional RF for BMR. BMR were isolated in 87 patients (31.8%) without RF. (AU)

Executive summary of the consensus document of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) on the diagnosis and antimicrobial treatment of infections due to carbapenem-resistant Gram-negative bacteria / Resumen ejecutivo del documento de consenso de la Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica (SEIMC) sobre el diagnóstico y tratamiento antimicrobiano de las infecciones por bacterias gramnegativas resistentes a carbapenémicos

Infections caused by multidrug resistant Gram-negative bacteria are becoming a worldwide problem due to their increasing incidence and associated high mortality. Carbapenem-resistant bacteria such as Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumannii are the most important in clinical practice. The objective of these guidelines is to update the recommendations for the diagnosis and treatment of infections caused by these multidrug resistant bacteria. Although ‘old’ antibiotics such as aminoglycosides, colistin, or tigecycline are frequently used for therapy of these bacteria, the ‘new’ beta-lactams such as ceftazidime–avibactam, ceftolozane–tazobactam, meropenem–vaborbactam, imipenem–cilastatin–relebactam or cefiderocol are progressively becoming the first-line therapy for most of these microorganisms. The Spanish Society of Infectious Diseases and Clinical Microbiology (Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica) designated a panel of experts in the field to provide evidence-based recommendations in response to common clinical questions. This document is primarily focused on microbiological diagnosis, clinical management, and targeted antimicrobial therapy of these infections, with special attention to defining the role of the new antimicrobials in the treatment of these bacteria.(AU)

Las infecciones causadas por bacterias gramnegativas multirresistentes se han convertido en un problema mundial debido a su creciente incidencia y alta mortalidad asociada. Las bacterias resistentes a carbapenémicos como Klebsiella pneumoniae, Pseudomonas aeruginosa y Acinetobacter baumannii son las más importantes en la práctica clínica. El objetivo de este documento de consenso es actualizar las recomendaciones sobre diagnóstico y tratamiento de las infecciones causadas por estas bacterias multirresistentes. Aunque los antibióticos ‘antiguos’ como aminoglucósidos, colistina o tigeciclina se utilizan con frecuencia en el tratamiento de estas bacterias, los ‘nuevos’ betalactámicos como ceftazidima-avibactam, ceftolozano-tazobactam, meropenem-vaborbactam, imipenem-cilastatina-relebactam o cefiderocol se están convirtiendo de forma progresiva en el tratamiento de primera elección para la mayoría de estos microorganismos. La Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica ha designado un grupo de expertos en la materia para elaborar una guía de recomendaciones basadas en la evidencia sobre las cuestiones clínicas más habituales. Este documento está principalmente centrado en el diagnóstico microbiológico, el manejo clínico y el tratamiento dirigido de estas infecciones, con especial referencia a definir el papel de los nuevos antimicrobianos en el tratamiento de estas bacterias.(AU)

Preventive isolation criteria for the detection of multidrug-resistant bacteria in patients admitted to the Intensive Care Unit: A multicenter study within the Zero Resistance program.

OBJECTIVE: To verify the validity of a checklist of risk factors (RFs) proposed by the Spanish "Zero Resistance" project (ZR) in the detection of multidrug-resistant bacteria (MRB), and to identify other possible RFs for colonization and infection by MRB on admission to the Intensive Care Unit (ICU). DESIGN: A prospective cohort study, conducted in 2016. SETTING: Multicenter study, patients requiring admission to adult ICUs that applied the ZR protocol and accepted the invitation for participating in the study. PATIENTS OR PARTICIPANTS: Consecutive sample of patients admitted to the ICU and who underwent surveillance (nasal, pharyngeal, axillary and rectal) or clinical cultures. INTERVENTIONS: Analysis of the RFs of the ZR project, in addition to other comorbidities, included in the ENVIN registry. A univariate and multivariate analysis was performed, with binary logistic regression methodology (significance considered for p < 0.05). Sensitivity and specificity analyses were performed for each of the selected factors. MAIN VARIABLES OF INTEREST: Carrier of MRB on admission to the ICU, RFs (previous MRB colonization/infection, hospital admission in the previous 3 months, antibiotic use in the past month, institutionalization, dialysis, and other chronic conditions) and comorbidities. RESULTS: A total of 2270 patients from 9 Spanish ICUs were included. We identified MRB in 288 (12.6% of the total patients admitted). In turn, 193 (68.2%) had some RF (OR 4.6, 95%CI: 3.5-6.0). All 6 RFs from the checklist reached statistical significance in the univariate analysis (sensitivity 66%, specificity 79%). Immunosuppression, antibiotic use on admission to the ICU and the male gender were additional RFs for MRB. MRB were isolated in 87 patients without RF (31.8%). CONCLUSIONS: Patients with at least one RF had an increased risk of being carriers of MRB. However, almost 32% of the MRB were isolated in patients without RFs. Other comorbidities such as immunosuppression, antibiotic use on admission to the ICU and the male gender could be considered as additional RFs.

COVID-19 associated infections in the ICU setting: A retrospective analysis in a tertiary-care hospital.

INTRODUCTION: Our work describes the frequency of superinfections in COVID-19 ICU patients and identifies risk factors for its appearance. Second, we evaluated ICU length of stay, in-hospital mortality and analyzed a subgroup of multidrug-resistant microorganisms (MDROs) infections. METHODS: Retrospective study conducted between March and June 2020. Superinfections were defined as appeared ≥48h. Bacterial and fungal infections were included, and sources were ventilator-associated lower respiratory tract infection (VA-LRTI), primary bloodstream infection (BSI), secondary BSI, and urinary tract infection (UTI). We performed a univariate analysis and a multivariate analysis of the risk factors. RESULTS: Two-hundred thirteen patients were included. We documented 174 episodes in 95 (44.6%) patients: 78 VA-LRTI, 66 primary BSI, 9 secondary BSI and 21 UTI. MDROs caused 29.3% of the episodes. The median time from admission to the first episode was 18 days and was longer in MDROs than in non-MDROs (28 vs. 16 days, p<0.01). In multivariate analysis use of corticosteroids (OR 4.9, 95% CI 1.4-16.9, p 0.01), tocilizumab (OR 2.4, 95% CI 1.1-5.9, p 0.03) and broad-spectrum antibiotics within first 7 days of admission (OR 2.5, 95% CI 1.2-5.1, p<0.01) were associated with superinfections. Patients with superinfections presented respect to controls prolonged ICU stay (35 vs. 12 days, p<0.01) but not higher in-hospital mortality (45.3% vs. 39.7%, p 0.13). CONCLUSIONS: Superinfections in ICU patients are frequent in late course of admission. Corticosteroids, tocilizumab, and previous broad-spectrum antibiotics are identified as risk factors for its development.

COVID-19 associated infections in the ICU setting: A retrospective analysis in a tertiary-care hospital / Sobreinfecciones en pacientes ingresados en UCI con COVID-19: análisis retrospectivo en un hospital de tercer nivel

Introduction: Our work describes the frequency of superinfections in COVID-19 ICU patients and identifies risk factors for its appearance. Second, we evaluated ICU length of stay, in-hospital mortality and analyzed a subgroup of multidrug-resistant microorganisms (MDROs) infections. Methods: Retrospective study conducted between March and June 2020. Superinfections were defined as appeared ≥48h. Bacterial and fungal infections were included, and sources were ventilator-associated lower respiratory tract infection (VA-LRTI), primary bloodstream infection (BSI), secondary BSI, and urinary tract infection (UTI). We performed a univariate analysis and a multivariate analysis of the risk factors. Results: Two-hundred thirteen patients were included. We documented 174 episodes in 95 (44.6%) patients: 78 VA-LRTI, 66 primary BSI, 9 secondary BSI and 21 UTI. MDROs caused 29.3% of the episodes. The median time from admission to the first episode was 18 days and was longer in MDROs than in non-MDROs (28 vs. 16 days, p<0.01). In multivariate analysis use of corticosteroids (OR 4.9, 95% CI 1.4–16.9, p 0.01), tocilizumab (OR 2.4, 95% CI 1.1–5.9, p 0.03) and broad-spectrum antibiotics within first 7 days of admission (OR 2.5, 95% CI 1.2–5.1, p<0.01) were associated with superinfections. Patients with superinfections presented respect to controls prolonged ICU stay (35 vs. 12 days, p<0.01) but not higher in-hospital mortality (45.3% vs. 39.7%, p 0.13). Conclusions: Superinfections in ICU patients are frequent in late course of admission. Corticosteroids, tocilizumab, and previous broad-spectrum antibiotics are identified as risk factors for its development.(AU)

Introducción: Nuestro trabajo describe la frecuencia de sobreinfecciones en pacientes con COVID-19 en UCI e identifica factores de riesgo asociados con su aparición. Secundariamente, evaluamos la estancia en UCI, mortalidad intrahospitalaria y analizamos un subgrupo de infecciones causadas por microorganismos multirresistentes (MDR). Métodos: Estudio realizado entre marzo y junio de 2020. Definimos como sobreinfección a aquellas que aparecieron ≥48h del ingreso. Incluimos las causadas por bacterias y hongos y evaluamos la infección respiratoria asociada a la ventilación mecánica (IRAVM), bacteriemia primaria, bacteriemia secundaria e infección del tracto urinario. Se realizó un análisis multivariante de los factores de riesgo. Resultados: Incluimos 213 pacientes, documentándose 174 episodios de sobreinfección en 95 casos (44,6%): IRAVM 78 episodios, bacteriemia primaria 66, bacteriemia secundaria 9 e ITU 21. Los MDR causaron el 29,3% de los episodios. La mediana de tiempo hasta el primer episodio fue de 18 días, siendo mayor en las causadas por MDR vs. no MDR (28 vs. 16, p<0,01). El análisis multivariante identificó la administración de corticoides (OR 4,9 IC 95% 1,4-16,9), tocilizumab (OR 2,4 IC 95% 1,1-5,9) y antibióticos de amplio espectro (OR 2,5 IC 95% 1,2-5,1) como factores de riesgo asociados. Los pacientes con sobreinfección presentaron una estancia en UCI más prolongada (35 vs. 12 días, p <0,01) pero no mayor mortalidad intrahospitalaria (45,3% vs. 39,7%, p 0,13). Conclusiones: Las sobreinfecciones en los pacientes con COVID-19 aparecen tardíamente. La administración de corticoides, tocilizumab y antibióticos de amplio espectro se asocia con su aparición.(AU)

Executive summary of the consensus document of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) on the diagnosis and antimicrobial treatment of infections due to carbapenem-resistant Gram-negative bacteria.

Infections caused by multidrug resistant Gram-negative bacteria are becoming a worldwide problem due to their increasing incidence and associated high mortality. Carbapenem-resistant bacteria such as Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumannii are the most important in clinical practice. The objective of these guidelines is to update the recommendations for the diagnosis and treatment of infections caused by these multidrug resistant bacteria. Although 'old' antibiotics such as aminoglycosides, colistin, or tigecycline are frequently used for therapy of these bacteria, the 'new' beta-lactams such as ceftazidime-avibactam, ceftolozane-tazobactam, meropenem-vaborbactam, imipenem-cilastatin-relebactam or cefiderocol are progressively becoming the first-line therapy for most of these microorganisms. The Spanish Society of Infectious Diseases and Clinical Microbiology (Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica) designated a panel of experts in the field to provide evidence-based recommendations in response to common clinical questions. This document is primarily focused on microbiological diagnosis, clinical management, and targeted antimicrobial therapy of these infections, with special attention to defining the role of the new antimicrobials in the treatment of these bacteria.

Implantación e impacto de un programa de control antibiótico y colonización por bacterias multirresistentes en una unidad de trasplante hepático / Implementation and impact of an antibiotic control program and multidrug-resistant bacterial colonization in a liver transplant unit

Introducción: las infecciones por bacterias multirresistentes constituyen una importante causa de morbimortalidad pre coz en los pacientes trasplantados.Propósito: se presenta un estudio unicéntrico, retrospectivo, con objetivo de evaluar la implantación de un programa de optimización del uso de antibióticos y de control epidemio lógico (PROA) en la colonización e infección por bacterias multirresistentes tras el trasplante hepático (TH).Métodos: se analizaron la colonización por bacterias multi rresistentes y las infecciones en el primer año postrasplante hepático (post-TH) en un grupo de 76 pacientes trasplanta dos en dos etapas, anterior y posterior al PROA, entre los años 2016 y 2019. Se analizaron variables clínicas relacio nadas con infección, reingresos y supervivencia a un año.Resultados: se produjo una buena adherencia al PROA. Las infecciones en el primer año post-TH fueron la causa más fre cuente de reingreso. La incidencia de infecciones fue similar en ambos periodos, con una media de 1,25 y 1,5 episodios de infección bacteriana por paciente/año con 19 episodios infecciosos bacterianos, seis por bacterias multirresistentes y de resistencia extendida (MDR-XDR) en la etapa pre-PROA y 18 episodios infecciosos bacterianos, cinco por MDR-XDR. en la etapa posterior. Se objetivó un descenso del 37 % post TH de colonización rectal por MDR-XDR durante el año 2019.Conclusión: las políticas de vigilancia epidemiológica y optimización de antibióticos son necesarias como estrategia de control del incremento de colonización e infección por bac terias multirresistentes en unidades de trasplante hepático. Son necesarios estudios a largo plazo para evaluar mejor el impacto de estos programas (AU)

Tratamiento de infecciones graves por Acinetobacter baumannii / Treatment of Acinetobacter baumannii severe infections

El Acinetobacter baumannii es un patógeno gramnegativo, multirresistente (MR) que causa infecciones nosocomiales, especialmente en las unidades de cuidados intensivos (UCI) y en los pacientes inmunocomprometidos. El A. baumannii ha desarrollado una resistencia antibiótica de amplio espectro, asociada con alta tasa de mortalidad entre los pacientes infectados comparada con las otras especies de Acinetobacter no baumannii. En relación con el impacto clínico, las cepas resistentes están asociadas con incremento de la estadía hospitalaria y de la mortalidad. El A. baumannii puede causar diferentes infecciones, especialmente neumonía asociada a la ventilación mecánica, bacteriemia, e infección de piel y partes blandas, entre otras. Los factores de riesgo más frecuentes para la adquisición de A. baumannii MR son el uso previo de antibióticos, la asistencia respiratoria mecánica, la estadía en la UCI y en el hospital, la severidad de la enfermedad y el uso de dispositivos médicos. Los esfuerzos actuales están focalizados en determinar todos los mecanismos de resistencia descritos en el A. baumannii, con el objetivo de identificar esquemas terapéuticos más efectivos (AU)

Acinetobacter baumannii is a Gram-negative, multidrug-resistant (MDR) pathogen that causes nosocomial infections, especially in intensive care units (ICUs) and immunocompromised patients. A. baumannii has developed a broad spectrum of antimicrobial resistance, associated with a higher mortality rate among infected patients compared with other non-baumannii species. In terms of clinical impact, resistant strains are associated with increases in both in-hospital length of stay and mortality. A. baumannii can cause a variety of infections, especially ventilator-associated pneumonia, bacteremia, and skin wound infections, among others. The most common risk factors for the acquisition of MDR A. baumannii are previous antibiotic use, mechanical ventilation, length of ICU and hospital stay, severity of illness, and use of medical devices. Current efforts are focused on addressing all the antimicrobial resistance mechanisms described in A. baumannii, with the objective of identifying the most promising therapeutic scheme (AU)

Antibióticos en desarrollo para bacilos gram negativos multirresistentes / Antibiotics in development for multiresistant gram-negative bacilli

El rápido incremento en las resistencias a los antibióticos entre los bacilos gram negativos (BGN), especialmente en cepas de enterobacterias, P. aeruginosa y A. baumannii, con elevados patrones de resistencia, plantea una enorme amenaza para los sistemas de salud en todo el mundo. En la última década diferentes antibióticos han sido desarrollados contra patrones de resistencia, algunos de los cuales combinan un β-lactámico junto con un inhibidor de β-lactamasa, mientras que otros utilizan inhibidores no β-lactámicos. La mayoría de ellos presenta una adecuada actividad in vitro sobre varias β-lactamasas de clase A, C y D de Ambler. Sin embargo, combinaciones como ceftazidime/avibactam, ceftolozano/tazobactam y meropenem/vaborbactam no presentan actividad contra metalo-β-lactamasas. Nuevas combinaciones como aztreonan/AVI, cefepime/zidebactam, o modernas cefalosporinas como cefiderocol, presentan eficacia contra casi la totalidad de las metalo-β-lactamasas. Aunque algunas de estas combinaciones ya están aprobadas y en fase de comercialización, muchas de ellas aún deben definir su lugar dentro del tratamiento de microorganismos con resistencia elevada a través de estudios clínicos (AU)

The rapid increase in antibiotic (ATB) resistance among Gram-negative bacilli(BGN), especially in strains of Enterobacteriaceae, Pseudomonas aeruginosa, and Acinetobacter baumannii, with high resistance patterns (XDR), poses a huge threat to health systems worldwide. In the last decade, different ATBs have been developed against XDR, some of which combine a lactam β along with a β-lactamase inhibitor, while others use non-β-lactam inhibitors. Most of them have adequate “in vitro” activity on several β-lactamases of class A, C and D of Ambler. However, combinations such as Ceftazidime/avibactam, Ceftolozane/Tazobactam and Meropenem/vaborbactam have no activity against metallo-β-lactamases(MβL). New combinations such as Aztreonan/AVI, Cefepime/Zidebactam, or new cephalosporins such as Cefiderocol, have efficacy against MβL enzymes. Although some of these combinations are already approved and in the commercialization phase, many of them have yet to define their place within the treatment of microorganisms with high resistance through clinical studies (AU)

Treatment of Acinetobacter baumannii severe infections.

Acinetobacter baumannii is a Gram-negative, multidrug-resistant (MDR) pathogen that causes nosocomial infections, especially in intensive care units (ICUs) and immunocompromised patients. A. baumannii has developed a broad spectrum of antimicrobial resistance, associated with a higher mortality rate among infected patients compared with other non-baumannii species. In terms of clinical impact, resistant strains are associated with increases in both in-hospital length of stay and mortality. A. baumannii can cause a variety of infections, especially ventilator-associated pneumonia, bacteremia, and skin wound infections, among others. The most common risk factors for the acquisition of MDR A. baumannii are previous antibiotic use, mechanical ventilation, length of ICU and hospital stay, severity of illness, and use of medical devices. Current efforts are focused on addressing all the antimicrobial resistance mechanisms described in A. baumannii, with the objective of identifying the most promising therapeutic scheme.

Antibiotics in development for multiresistant gram-negative bacilli.

The rapid increase in antibiotic(ATB) resistance among Gram-negative bacilli(BGN), especially in strains of Enterobacteriaceae, Pseudomonas aeruginosa, and Acinetobacter baumannii, with high resistance patterns (XDR), poses a huge threat to health systems worldwide. In the last decade, different ATBs have been developed against XDR, some of which combine a lactam ß along with a ß-lactamase inhibitor, while others use non-ß-lactam inhibitors. Most of them have adequate "in vitro" activity on several ß-lactamases of class A, C and D of Ambler. However, combinations such as Ceftazidime/avibactam, Ceftolozane/Tazobactam and Meropenem/vaborbactam have no activity against metallo-ß-lactamases(MßL). New combinations such as Aztreonan/AVI, Cefepime/Zidebactam, or new cephalosporins such as Cefiderocol, have efficacy against MßL enzymes. Although some of these combinations are already approved and in the commercialization phase, many of them have yet to define their place within the treatment of microorganisms with high resistance through clinical studies.

Programa de prevención de Enterobacterias Productoras de Carbapenemasas en unidades críticas en Argentina durante la pandemia COVID-19 / Program for the prevention of Carbapenemase-Producing Enterobacteria in critical units in Argentina during the COVID-19 pandemic

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.

Tratamiento de las infecciones graves por Pseudomonas aeruginosa multirresistente / Treatment of severe multi-drug resistant Pseudomonas aeruginosa infections

Pseudomonas aeruginosa es el microorganismo que participa con mayor frecuencia en las principales infecciones adquiridas en la UCI, con especial importancia en la neumonía asociada a ventilación mecánica. Su importancia radica, además de en su elevada incidencia en el paciente crítico, en la gravedad de las infecciones que causa y en la dificultad de su tratamiento antimicrobiano, directamente relacionada con el elevado porcentaje de resistencias a los antibióticos considerados clásicamente de primera línea. Recientemente se han desarrollado nuevos antibióticos activos frente a Pseudomonas aeruginosa, incluso frente a cepas multirresistentes. La presente revisión analiza tanto las características diferenciales de las infecciones por Pseudomonas aeruginosa como las nuevas opciones terapéuticas, centrando el foco en la Pseudomonas aeruginosa multirresistente (AU)

Pseudomonas aeruginosa is the microorganism most frequently involved in the main ICU-acquired infections, with special importance in ventilator associated pneumonia. Its importance lies, in addition to its high incidence in critically ill patients, in the severity of the infections it causes and in the difficulty of its antimicrobial treatment, directly related to the high percentage of resistance to antibiotics classically considered first-line. New active antibiotics have recently been developed against Pseudomonas aeruginosa, even against multi-drug resistant strains. This review analyzes both the differential characteristics of Pseudomonas aeruginosa infections and the new therapeutic options, focusing on multi-drug resistant Pseudomonas aeruginosa (AU)

El papel del laboratorio de microbiología en el diagnóstico de infecciones por bacilos gramnegativos multirresistentes. Importancia de la determinación de mecanismos de resistencias / The role of the microbiology laboratory in the diagnosis of multidrug-resistant Gram-negative bacilli infections. Importance of the determination of resistance mechanisms

Un diagnóstico y tratamiento precoz tiene un impacto importante en la morbimortalidad de las infecciones producidas por bacterias multirresistentes. Los bacilos gramnegativos multirresistentes constituyen la principal amenaza actual en los hospitales y muy especialmente en las unidades de cuidados intensivos. El papel del laboratorio de microbiología es esencial en dar una respuesta rápida y eficaz. En esta revisión se actualiza los procedimientos del laboratorio de microbiología para la detección rápida de los bacilos gramnegativos multirresistentes y de sus determinantes de resistencia. También se estudia el papel del laboratorio en la vigilancia y control de brotes por estas bacterias, incluyendo las técnicas de tipificación. Se destaca la importancia de proporcionar mapas de resistencia normalizados que permitan conocer la situación epidemiológica de las diferentes unidades. Finalmente se revisa la importancia de sistemas de comunicación eficaces para la transmisión de resultados y la toma de decisiones en el manejo de pacientes infectados por bacilos gramnegativos multirresistentes (AU)

Early diagnosis and treatment has an important impact on the morbidity and mortality of infections caused by multidrug-resistant bacteria. Multidrug-resistant gram-negative bacilli constitute the main current threat in hospitals and especially in intensive care units. The role of the microbiology laboratory is essential in providing a rapid and effective response. This review updates the microbiology laboratory procedures for the rapid detection of multidrug-resistant gram-negative bacilli and its resistance determinants. The role of the laboratory in the surveillance and control of outbreaks caused by these bacteria, including typing techniques, is also studied. The importance of providing standardized resistance maps that allow knowing the epidemiological situation of the different units is emphasized. Finally, the importance of effective communication systems for the transmission of results and decision making in the management of patients infected by multidrug-resistant gram-negative bacilli is reviewed (AU)

Treatment of severe multi-drug resistant Pseudomonas aeruginosa infections.

Pseudomonas aeruginosa is the microorganism most frequently involved in the main ICU-acquired infections, with special importance in ventilator associated pneumonia. Its importance lies, in addition to its high incidence in critically ill patients, in the severity of the infections it causes and in the difficulty of its antimicrobial treatment, directly related to the high percentage of resistance to antibiotics classically considered first-line. New active antibiotics have recently been developed against Pseudomonas aeruginosa, even against multi-drug resistant strains. This review analyzes both the differential characteristics of Pseudomonas aeruginosa infections and the new therapeutic options, focusing on multi-drug resistant Pseudomonas aeruginosa.

The role of the microbiology laboratory in the diagnosis of multidrug-resistant Gram-negative bacilli infections. The importance of the determination of resistance mechanisms.

Early diagnosis and treatment has an important impact on the morbidity and mortality of infections caused by multidrug-resistant bacteria. Multidrug-resistant gram-negative bacilli (MR-GNB) constitute the main current threat in hospitals and especially in intensive care units (ICU). The role of the microbiology laboratory is essential in providing a rapid and effective response. This review updates the microbiology laboratory procedures for the rapid detection of BGN-MR and its resistance determinants. The role of the laboratory in the surveillance and control of outbreaks caused by these bacteria, including typing techniques, is also studied. The importance of providing standardized resistance maps that allow knowing the epidemiological situation of the different units is emphasized. Finally, the importance of effective communication systems for the transmission of results and decision making in the management of patients infected by BGN-MR is reviewed.

Cerebrospinal fluid drainage-related ventriculitis due to multidrug-resistant microorganisms.

INTRODUCTION: The aim of the study was to analyze the clinical and microbiological characteristics of adult patients with cerebrospinal fluid (CSF) drainage-related ventriculitis. METHODS: Retrospective study from January 2010 to June 2019 performed in the Complexo Hospitalario Universitario de Vigo (Spain). Cases of CSF drainage-related ventriculitis in patients ≥18-year-old were gathered. Clinical characteristics of patients, type of drainage devices, management and microbiological isolates were analyzed. RESULTS: Ninety-one episodes of CSF drainage-related ventriculitis were identified. The most frequent organisms isolated were Gram-positive cocci (65%), mainly Staphylococcus epidermidis (48%). Multidrug-resistant microorganisms were detected in 21 episodes (23%). In multivariate analysis, the independent factors related with multidrug-resistant ventriculitis were the length of hospital stay >14 days (HR 6.7; 95%CI 1.75-25.86, p=0.006) and previous antimicrobial therapy (HR 5.58; 95%CI 1.44-21.65, p=0.013). CONCLUSIONS: Our study shows a large number of drainage-related ventriculitis episodes caused by multidrug-resistant organisms and reinforce the importance of a judicious use of antibiotics.

The efficiency of cleaning in intensive care units: A systematic review.

OBJECTIVES: This review aims to analyze the studies on cleaning practices and the efficiency of the cleaning carried out in environments that have a great risk of resistant microorganism infection, such as intensive care units. METHODS: In this study, a retrospective literature review was undertaken of the relevant publications between the years 2005 and 2020, using the keywords "Cross Infection, Infection Control, Multidrug-Resistant Bacteria, Intensive Care, Room Cleaning, Environmental Cleaning, Hospital-Associated Infection"; using the international databases Pubmed, CINAHL and EBSCO and domestic database ULAKBIM on search engines. Titles and abstracts of all relevant articles found on electronic searches were reviewed by the researchers independently. The Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols guideline and Patient, Intervention, Comparison, Outcomes, Study design model were used in analysing the studies. RESULTS: The selected studies were reviewed in four main categories: Materials used in cleaning, the period between taking environmental samples, cleaning methods, and the efficiency of cleaning. Among the studies included herein, eight were randomized controlled trials, three were retrospective intervention studies, two were case-control studies and one was a retrospective cohort study. CONCLUSIONS: Today, the assessment of cleaning in environments can be evaluated by different methods, but there are advantages and disadvantages of these methods. Therefore, in the relevant literature, it is suggested that cleaning must be evaluated by several methods, not only one. Also, training the staff that carries out the cleaning and rewarding correct behavior by giving feedback are important approaches to increase the efficiency of cleaning. It is suggested that cleaning must be carried out every day, regularly with effective methods and equipment; frequency of cleaning during epidemics must be increased, institutions must prepare cleaning manuals according to evidence-based guidelines that are recognized at an international level.