Introduction: Infection with carbapenemase-producing Gramnegative bacilli (CP-GNB) carries high morbidity and mortality in cancer patients, and intestinal colonization is a risk factor. Objective: To estimate the prevalence of rectal carriage and the risk of infection with CP-GNB in cancer patients. Methodology: Positive microbiological results (carriage and culture of clinical samples) for CP-GNB were reviewed in cancer patients hospitalized between January 2023 and June 2024. The relationship between rectal carriage and the subsequent onset of clinical infections was assessed with a chisquare test and a bivariate logistic regression model. Results: Of 2,172 patients, 149 (6.9%) were carriers of CP-GNB, with no differences according to cancer type. Of these, 13.4% developed an infection vs. 1.2% of those not colonized (p <= 0.001); this was significantly associated with a higher risk of clinical infection (OR = 12.39; 95% CI: 6.7-22.9; p <= 0.001). Discussion: Colonization with CP-GNB was a significant risk for developing clinical infection in cancer patients in our institution, regardless of the cancer type. Carriage surveillance is essential for stratifying individual infection risk and optimizing antimicrobial treatment.

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 (SD 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% of the HCW had to take SL in the period and in 12,97% infection was confirmed by PCR. Distribution by sex and age did not differ from the distribution of total HCW in CLC. Among confirmed cases, most of them were HCA, whereas in the CC group the majority were CA. Regarding HCA cases, it stands out that the first case occurred 63 days after the first COVID-19 inpatient in CLC when the epidemic was already spread in the community, which reflects the effectiveness of the preventive measures adopted within CLC.

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.

La aparicion de la enfermedad por SARS-CoV-2 el ano 2020 nos enfrento a un aumento creciente y exponencial de pacientes con riesgo vital por falla respiratoria catastrofica y multisistemica que deben ser sometidos a ECMO para sobrevivir. Esto ha generado en nuestro pais la aparicion de Unidades de Tratamiento ECMO en hospitales en que antes no se disponia de este recurso o se realizaba como parte de las intervenciones en Unidades de Cuidados Intensivos (UCI), lo que constituye un nuevo desafio a los programas de control y prevencion de infecciones de los centros de salud. Dado que al momento de la redaccion de este documento no existe normativa nacional especifica que se refiera a este tema, se propone un enfoque para prevencion, control y vigilancia de infecciones asociadas a atencion de salud en pacientes ECMO. Se presenta una revision de los riesgos especificos a que estan expuestos estos pacientes, definiendo que medidas de prevencion se requieren, proponiendo un conjunto de medidas especificas para instalacion y mantencion, asi como orientacion respecto de antibioprofilaxis y se sugiere que eventos infecciosos vigilar.

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% of the HCW had to take SL in the period and in 12,97% infection was confirmed by PCR. Distribution by sex and age did not differ from the distribution of total HCW in CLC. Among confirmed cases, most of them were HCA, whereas in the CC group the majority were CA. Regarding HCA cases, it stands out that the first case occurred 63 days after the first COVID-19 inpatient in CLC, when the epidemic was already spread in the community, which reflects the effectiveness of the preventive measures adopted within CLC.

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-dependentStaphylococcus aureusstrain 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-resistantStaphylococcus aureuswith a type I SCCmeccassette 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.

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.

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.

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 international 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.

Use of mass spectrometry for rapid diagnosis of positive blood cultures. Validation of a local algorythmMass 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.

A diferencia de otras áreas del laboratorio, la automatización del laboratorio de microbiología no ha sido fácil, sin embargo es una necesidad clínica para mejorar el manejo de pacientes críticos. Para lograr este objetivo, es necesario optimizar la productividad y flujos de trabajo, partiendo desde el pre-analítico, pasando por los diferentes test de identificación y susceptibilidad, hasta el post-analítico, que en gran medida se ha automatizado a través de la informatización de los resultados. Se muestra en este documento, cuáles son algunos avances en las diferentes áreas, respecto de las metodologías tradicionales, proponiendo esquemas de trabajo para identificación precoz mediante metodología MALDI-TOF, así como elementos de juicio para realizar un correcto informe de antibiograma. La implementación de metodologías rápidas y automatizadas en el laboratorio de microbiología implica una adaptación del personal técnico y profesional, interpretando correctamente los resultados obtenidos, tanto en identificación como en estudios de susceptibilidad. También constituye una exigencia para los administradores, que deben hacer las inversiones necesarias y modificaciones en la planta física y humana, para mantener el servicio en una base de 24/7, aprovechando al máximo las ventajas ofrecidas por la automatización de los procesos.

Catheter-related bloodstream infection in hemodialysis is a serious and difficult to diagnose complication because there may be few or absence of clinical signs suggestive of sepsis and there is lack of a well established gold standard method for laboratory diagnosis. There have been a number of proposed methods for diagnosing these infections in the microbiology laboratory; in order to avoid the unnecessary catheter removal, blood cultures methods that permit diagnosis with the catheter in place must be attempted. Because of the importance of blood cultures as the main diagnostic tool, recommendations are needed to standardize the adequate collection and transport of specimens, the optimal laboratory processing method for diagnosis and the correct interpretation of results.

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.

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.

Las Infecciones Asociadas a la Atención Sanitaria (IAAS) por Microorganismos Multirresistentes (MOMR), son una realidad generadora de brotes intrahospitalarios difíciles de erradicar. Dentro de las formas de manejo internacionalmente aceptadas destacan el uso racional de antimicrobianos y el aislamiento de los casos detectados. Para detectar los casos, CLC realiza simultáneamente tres tipos de vigilancia y frente a la presencia de MOMR en cualquiera de estas vigilancias, se establecen medidas de aislamiento de contacto. El objetivo del presente trabajo es evaluar el estado de colonización por MOMR en pacientes trasladados desde otro centro asistencial, mediante cultivo nasal y rectal.

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.