Oxigenación por membrana extracorpórea (ECMO): una mirada desde la prevención de Infecciones Asociadas a la Atención en Salud (IAAS) / Extracorporeal membrane oxygenation (ECMO): an infection control perspective

Resumen La aparición de la enfermedad por SARS-CoV-2 el año 2020 nos enfrentó a un aumento creciente y exponencial de pacientes con riesgo vital por falla respiratoria catastrófica y multisistémica que deben ser sometidos a ECMO para sobrevivir. Esto ha generado en nuestro país la aparición de Unidades de Tratamiento (ECMO) en hospitales en que antes no se disponía de este recurso o se realizaba como parte de las intervenciones en Unidades de Cuidados Intensivos (UCI), lo que constituye un nuevo desafío a los programas de control y prevención de infecciones de los centros de salud. Dado que al momento de la redacción de este documento no existe normativa nacional específica que se refiera a este tema, se propone un enfoque para prevención, control y vigilancia de infecciones asociadas a atención de salud en pacientes ECMO. Se presenta una revisión de los riesgos específicos a que están expuestos estos pacientes, definiendo qué medidas de prevención se requieren, proponiendo un conjunto de medidas específicas para instalación y mantención, así como orientación respecto de antibioprofilaxis y se sugiere qué eventos infecciosos vigilar.

Abstract The advent of SARS-CoV-2 disease in 2020 confronts us with a growing and exponential increase in patients at life risk due to catastrophic and multisystemic respiratory failure in need of extracorporeal membrane oxygenation (ECMO) to survive. This has generated in our country the establishment of ECMO treatment Units in hospitals where it was not carried out before or was carried out as part the interventions in Intensive Care Units (ICU), becoming a new challenge to the infection control and prevention programs. Given that at the time of writing this document there are no specific national regulations that refer to this issue, an approach is proposed for the prevention control and surveillance of nosocomial acquired infections in ECMO patients. A review of the specific risks to which these patients are exposed is presented, defining which prevention measures are required, proposing a specific bundle for installation and maintenance, as well as guidance regarding antibioprophylaxis and suggesting which infectious events to monitor.

Impacto de la primera ola pandémica de COVID-19 en el personal de salud en un hospital privado / Impact of the first pandemic wave of COVID-19 on health-care workers in a private hospital

El personal de salud (PS) está más expuesto que la población general a enfermar por SARS-CoV-2, por lo que debe utilizar elementos de protección personal (EPP) en todas las atenciones. El PS de Clínica Las Condes (CLC) que requirió licencia médica (LM) por COVID-19 durante el periodo de estudio, fue evaluado por Organismo Administrador según Ley 16.744, categorizando cada caso de contacto estrecho (CE) o contagio, en común o laboral. Además, fue contactado en su totalidad por equipo de RRHH y de IAAS, para conocer estado de salud, factores de riesgo y evolución. El objetivo fue caracterizar los casos y CE de PS que tuvieron LM, relacionándolas con diferentes eventos ocurridos en la institución y la comunidad durante el periodo comprendido entre el 12 de febrero y el 31 de julio. Un 21% del PS requirió LM en el periodo y un 12,97% presentó infección confirmada por PCR. En cuanto a la distribución por sexo y edad de casos y CE, esta no difiere de la distribución observada en el total de funcionarios de CLC. Se observa que, en los casos, la mayoría corresponde a categoría intrahospitalaria, en cambio los CE, la mayor parte correspondió a comunitario. En relación con casos confirmados intrahospitalarios, destaca que el primer caso ocurrió 63 días después del primer paciente hospitalizado en CLC con diagnóstico de COVID-19, y cuando ya estaba instalada la epidemia en la Región Metropolitana (RM) de Santiago , lo que refleja la efectividad de las medidas de prevención adoptadas al interior de CLC.

Health care workers (HCW) are at higher risk to get sick from SARS-CoV-2 than general population, so they must use personal protective equipment (PPE) in all care situations. The HCW at Clinica las Condes (CLC) that required a sick leave (SL) during the study period was evaluated by the Administrative Institution according to Law 16.744, which categorized each case of close contact (CC) or confirmed case, as community-acquired (CA) or health care-associated (HCA). In addition, all of them were traced by the HR and Infection Control team, to find out health status, risk factors and evolution. The aims were to characterize the confirmed cases and CC, their association with key events that occurred in the institution and the community between February 12th and July 31th. 21%

[Extracorporeal membrane oxygenation (ECMO): an infection control perspective]. / Oxigenación por membrana extracorpórea (ECMO): una mirada desde la prevención de Infecciones Asociadas a la Atención en Salud (IAAS).

The advent of SARS-CoV-2 disease in 2020 confronts us with a growing and exponential increase in patients at life risk due to catastrophic and multisystemic respiratory failure in need of extracorporeal membrane oxygenation (ECMO) to survive. This has generated in our country the establishment of ECMO treatment Units in hospitals where it was not carried out before or was carried out as part the interventions in Intensive Care Units (ICU), becoming a new challenge to the infection control and prevention programs. Given that at the time of writing this document there are no specific national regulations that refer to this issue, an approach is proposed for the prevention control and surveillance of nosocomial acquired infections in ECMO patients. A review of the specific risks to which these patients are exposed is presented, defining which prevention measures are required, proposing a specific bundle for installation and maintenance, as well as guidance regarding antibioprophylaxis and suggesting which infectious events to monitor.

Isolation and first draft genome sequence of a linezolid-dependent Staphylococcus aureus clinical strain.

Background: Antibiotic-dependent pathogenic bacteria are sporadically isolated from patients that received prolonged antibiotic treatments. Evolution of antibiotics dependence and its clinical implications are scarcely studied. Materials & methods: A linezolid-dependent Staphylococcus aureus strain was isolated from a cystic fibrosis patient. A draft genome sequence was obtained and searched for known antibiotics resistance determinants and virulence factors. Results: The genome was assembled into 79 contigs for a total of 2.83 Mbp. This strain is a sequence type 5 methicillin-resistant Staphylococcus aureus with a type I SCCmec cassette also conserving the Panton-Valentine leukocidin. The G2576T substitution, conferring linezolid resistance, was harbored by all five copies of the 23S rRNA. Conclusion: The linezolid-dependent strain is related to a strain circulating in Latin America that acquired a mutation conferring linezolid resistance.

[Susceptibility to first-generation Cephalosporins in Enterobacteriaceae isolated from urine culture according to CLSI and EUCAST breakpoints]. / Estudio de susceptibilidad a cefalosporinas de primera generación en enterobacterias aisladas de urocultivo, según criterios CLSI y EUCAST.

Currently, the use of cefazolin is recommended to determine the susceptibility to first-generation oral cephalosporins in strains of enterobacteria in uncomplicated UTI. We determined susceptibility differences to oral cephalosporins in urinary strains according to cefazolin or cefalotin breakpoints and the correlation of susceptibility between cefazolin and cefadroxil. We studied 52 strains with cefalotin and cefazolin by disk-diffusion and MIC (Kirby-Bauer and Vitek XL) and a subgroup by disk-diffusion for cefadroxil. Agreement among different methods was 100% for K. pneumoniae and Proteus spp. In Escherichia coli, agreement for Vitek and disk-diffusion were 0 and 50% respectively. Susceptibility to first generation cephalosporins in E. coli should be determined with cefazolin. Agreement between cefazolin and cefadroxil suggests that cefazolin could also predict the susceptibility of cefadroxil.

Estudio de susceptibilidad a cefalosporinas de primera generación en enterobacterias aisladas de urocultivo, según criterios CLSI y EUCAST / Susceptibility to first-generation Cephalosporins in Enterobacteriaceae isolated from urine culture according to CLSI and EUCAST breakpoints

Resumen Actualmente se recomienda el uso de cefazolina para determinar la susceptibilidad a cefalosporinas orales de primera generación en cepas de enterobacterias en ITU no complicada. Nuestro objetivo fue establecer la susceptibilidad a cefalosporinas orales en cepas urinarias según puntos de corte para cefalotina o cefazolina y la correlación de susceptibilidad entre cefazolina y cefadroxilo. Se estudió la concordancia entre cefalotina y cefazolina en 52 cepas por método de Kirby-Bauer y Vitek XL. En Escherichia coli fue de 0% para VitekXL y 50% para Kirby-Bauer. La concordancia entre cefazolina y cefadroxilo fue 95,6%. En el laboratorio debiera usarse cefazolina para determinar susceptibilidad a cefalosporinas orales de primera generación. La concordancia entre cefazolina y cefadroxilo sugiere que cefazolina podría predecir susceptibilidad para cefadroxilo.

Currently, the use of cefazolin is recommended to determine the susceptibility to first-generation oral cephalosporins in strains of enterobacteria in uncomplicated UTI. We determined susceptibility differences to oral cephalosporins in urinary strains according to cefazolin or cefalotin breakpoints and the correlation of susceptibility between cefazolin and cefadroxil. We studied 52 strains with cefalotin and cefazolin by disk-diffusion and MIC (Kirby-Bauer and Vitek XL) and a subgroup by disk-diffusion for cefadroxil. Agreement among different methods was 100% for K. pneumoniae and Proteus spp. In Escherichia coli, agreement for Vitek and disk-diffusion were 0 and 50% respectively. Susceptibility to first generation cephalosporins in E. coli should be determined with cefazolin. Agreement between cefazolin and cefadroxil suggests that cefazolin could also predict the susceptibility of cefadroxil.

[Antiseptics and disinfectants: aiming at rational use. Recommendations of the Advisory Committee on Healthcare Associated Infections. Sociedad Chilena de Infectología]. / Antisépticos y desinfectantes: apuntando al uso racional. Recomendaciones del Comité Consultivo de Infecciones Asociadas a la Atención de Salud, Sociedad Chilena de Infectología.

Proper use of antiseptics and disinfectants, is an essential tool to prevent the spread of infectious agents and to control of healthcare-associated infections (HAI). Given the increasing importance of environmental aspects, as well as several advances and updates in the field of its proper use at local and intemational level, the SOCHINF HAI Advisory Committee considers that it is necessary to develop a guide for the rational use of antiseptics and disinfectants, which it will provide consistent scientific basis with that purpose.

Antisépticos y desinfectantes: apuntando al uso racional. Recomendaciones del Comité Consultivo de Infecciones Asociadas a la Atención de Salud, Sociedad Chilena de Infectología / Antiseptics and disinfectants: aiming at rational use. Recommendations of the Advisory Committee on Healthcare Associated Infections. Sociedad Chilena de Infectología

Proper use of antiseptics and disinfectants, is an essential tool to prevent the spread of infectious agents and to control of healthcare-associated infections (HAI). Given the increasing importance of environmental aspects, as well as several advances and updates in the field of its proper use at local and intemational level, the SOCHINF HAI Advisory Committee considers that it is necessary to develop a guide for the rational use of antiseptics and disinfectants, which it will provide consistent scientific basis with that purpose.

El adecuado uso de antisépticos y desinfectantes, es una herramienta esencial para evitar la diseminación de agentes infecciosos y el control de infecciones asociadas a la atención de salud (IAAS). Dada la importancia creciente de aspectos ambientales, diversos avances y actualizaciones en el ámbito de su correcta utilización en el ámbito local e internacional, el Comité Consultivo de IAAS de Sociedad Chilena de Infectología considera necesario la estructuración de una guía de utilización racional de antisépticos y desinfectantes, que proporcione bases científicas coherentes con dicho propósito.

[Outbreak due to Serratia marcescens associated with intrinsic contamination of aqueous chlorhexidine]. / Brote de infección nosocomial por Serratia marcescens asociado a contaminación intrínseca de clorhexidina acuosa.

Serratia marcescens is a widely distributed gram-negative rod, often associated to nosocomial infections. Some outbreaks linked to contaminated antiseptic solutions have been reported. In this study we report a nosocomial outbreak of surgical site infection and catheter insertion site infection due to S. marcescens. 33 patients with positive cultures were studied after an index case was identified. Epidemiological, microbiological and molecular analysis demostrated an intrinsic contamination of alcohol free chlorhexidine solution as causal factor. Positive cultures were associated with 13 clinical infections, 9 colonized patients, 6 pseudobacteremia episodes and 5 patients without documented exposure. Hospital and national recall of contaminated chlorhexidine solution was performed after this study. Intrinsic contamination of antiseptic solutions is an infrequent cause of nosocomial infections with major epidemiological relevance.

[Use of mass spectrometry for rapid diagnosis of positive blood cultures: Validation of a local algorythm]. / Utilización de espectrometría de masas para la identificación precoz de hemocultivos positivos: Validación de un algoritmo local.

Mass spectrometry (MS) is used in identification of positive blood culture, a contribution in the clinical management of septic patients. The protocol is labor intensive and disrupts the normal workflow in a clinical laboratory. We intended to make rapid diagnosis by using MS directly from shortly incubated blood agar plates (4 to 6 hours) comparing with results of the conventional method (MC). We worked in parallel 145 positive blood cultures, with correct identification by short method in 79% of cases. We observed better yield with non carbon bottles and with gramnegative rods. With this information we designed a rapid identification algorithm using MS, which allows advancing diagnosis in 12-16 hours, without increasing to the costs or work load, since extraction protocol is not used.

Brote de infección nosocomial por Serratia marcescens asociado a contaminación intrínseca de clorhexidina acuosa / Outbreak due to Serratia marcescens associated with intrinsic contamination of aqueous chlorhexidine

Serratia marcescens is a widely distributed gram-negative rod, often associated to nosocomial infections. Some outbreaks linked to contaminated antiseptic solutions have been reported. In this study we report a nosocomial outbreak of surgical site infection and catheter insertion site infection due to S. marcescens. 33 patients with positive cultures were studied after an index case was identified. Epidemiological, microbiological and molecular analysis demostrated an intrinsic contamination of alcohol free chlorhexidine solution as causal factor. Positive cultures were associated with 13 clinical infections, 9 colonized patients, 6 pseudobacteremia episodes and 5 patients without documented exposure. Hospital and national recall of contaminated chlorhexidine solution was performed after this study. Intrinsic contamination of antiseptic solutions is an infrequent cause of nosocomial infections with major epidemiological relevance.

Serratia marcescens es un bacilo gramnegativo de amplia distribución, frecuentemente asociado a infecciones nosocomiales. Se han descrito brotes asociados a la contaminación de diversas soluciones antisépticas. Describimos a continuación un brote de infección de sitio operatorio (ISO) y de infección de sitio de inserción de catéter vascular (ISC) por S. marcescens. A raíz de un caso índice se estudió un total de 33 pacientes con cultivo positivo para S. marcescens. El análisis epidemiológico, microbiológico y molecular logró demostrar la contaminación intrínseca de un lote de clorhexidina acuosa, como fuente común de exposición. Las muestras positivas correspondieron a 13 infecciones clínicas, nueve colonizaciones, seis pseudo-bacteriemias y cinco pacientes sin exposición demostrada. Los resultados de este estudio determinaron el retiro del producto de la institución y posteriormente a nivel nacional. La contaminación intrínseca de antisépticos es una causa poco frecuente de brotes de infecciones nosocomiales cuya identificación posee un gran impacto epidemiológico.

Utilización de espectrometría de masas para la identificación precoz de hemocultivos positivos: Validación de un algoritmo local / Use of mass spectrometry for rapid diagnosis of positive blood cultures: Validation of a local algorythm

Mass spectrometry (MS) is used in identification of positive blood culture, a contribution in the clinical management of septic patients. The protocol is labor intensive and disrupts the normal workflow in a clinical laboratory. We intended to make rapid diagnosis by using MS directly from shortly incubated blood agar plates (4 to 6 hours) comparing with results of the conventional method (MC). We worked in parallel 145 positive blood cultures, with correct identification by short method in 79% of cases. We observed better yield with non carbon bottles and with gramnegative rods. With this information we designed a rapid identification algorithm using MS, which allows advancing diagnosis in 12-16 hours, without increasing to the costs or work load, since extraction protocol is not used.

Espectrometría de masas (EM) es utilizada en identificación de hemocultivo positivo (HMP), constituyendo un aporte en el manejo clínico de paciente séptico. El protocolo de identificación directa es ultra laborioso, interrumpiendo el flujo de trabajo normal del laboratorio. Con el objetivo de hacer identificación rápida, utilizamos EM a partir de placas de agar sangre con incubación breve (4 a 6 h), comparando resultados con el método convencional en HMP. Se trabajó 145 frascos de HMP, identificando correctamente por método acortado 79% de los microorganismos. El rendimiento fue mejor en frascos sin carbón activado y en la identificación de bacilos gramnegativo. Con esta información, diseñamos algoritmo para la identificación precoz de hemocultivo positivo mediante EM, procesando a ciegas a las 4 a 6 h de incubación, lo que permite adelantar el diagnóstico en 12-16 h respecto del método tradicional, sin aumentar los costos ni la carga de trabajo, ya que no se utiliza protocolo de extracción.

Impact of the novel influenza A (H1N1) during the 2009 autumn-winter season in a large hospital setting in Santiago, Chile.

BACKGROUND: In Chile, the novel influenza A (H1N1) epidemic began in the middle-high income area of Santiago. Clinical and laboratory surveillance was intensified with the aim to characterize the epidemic and determine its impact in a large hospital setting. METHODS: Demographic and clinical data were obtained from all patients whose symptoms met the clinical definition of influenza A (H1N1) infection during the epidemic period. Laboratory confirmation was obtained by use of a nasopharyngeal antigen detection test for influenza A and/or influenza A (H1N1) polymerase chain reaction (PCR). A case was considered confirmed if the antigen detection test result for influenza A and/or the PCR test result were positive. RESULTS: The total number of emergency department (ED) visits increased by 88.5% from a mean of 14,489 ED visits in 2006-2008 to a mean of 27,308 ED visits in 2009, during the epidemic period. There were 10,048 patients who were clinically diagnosed with influenza A (H1N1), and they represented 78% of all visits, of which 4591 (45.6%) were laboratory confirmed. The median time from symptom onset to diagnosis was 1 day, and 99.7% of individuals received antiviral treatment. School-aged children represented 67% of ED visits at the beginning of the epidemic and 24% of ED visits at the end of the epidemic. Only 2% of cases were hospitalized; of these, 70% of cases occurred in patients 6-50 years of age, and 32% of cases occurred in patients who had an underlying medical condition. Eleven patients (age range, 1-53 years) required admission to the intensive care unit (ICU); 6 of these patients had pneumonia with or without hemodynamic shock. No influenza-associated deaths occurred. CONCLUSIONS: Many cases of influenza A (H1N1) occurred in school-aged and adult individuals who required an ED visit; these visits resulted in a low impact on the use of hospital beds. Aggressive ICU management and/or experience in extracorporeal membrane oxygenation significantly improved outcomes. Early antiviral treatment may have played an important role in the low number of severe cases. Vaccines targeted for school-aged children and young adults may modify the first epidemic wave in the northern hemisphere.