Hypervirulent Strains of Neisseria meningitidis and Clinical Manifestations in Children With Invasive Meningococcal Disease.

BACKGROUND: Hypervirulent clonal complex (cc) have been associated with higher incidence and case fatality rate of invasive meningococcal disease (IMD). The aim of this study was to describe the clinical manifestations of the hypervirulent cc of meningococcus in children. METHODS: Retrospective study in patients hospitalized by IMD microbiologically confirmed at three children's tertiary health care centers in Santiago, Chile, between 2010 and 2018. Demographic, clinical information and determination of the cc and factor H binding protein (fHbp) alleles were performed. RESULTS: In total 93 cases were evaluated, sequence typing was available for 91 cases, and 87 (95.6%) had a cc assigned; 63.7% were MenW and 31.8% MenB. The median age was 9 months, 67% were male and 18.7% had any comorbidity. A 26.4% presented neurological deficit, 25.3% petechiae and 20% diarrhea. Sixty-seven percent were admitted to the pediatric intensive care unit (PICU) and the case fatality rate was 9.9%. Regarding cc and fHbp alleles, ST11, ST41/44 and allele 22 were the most frequently identified, with 63.7%, 19.8% and 72.5%, respectively. We found statistically significant differences between the cc and presence of petechiae, diagnosis of meningococcemia plus meningitis, admission and days in PICU and advanced support. Allele 22 for fHbp was associated with the absence of petechiae, low suspicion of IMD, less diagnosis of meningitis+meningococcemia, PICU admission, advanced support and adrenal insufficiency. CONCLUSION: Epidemiological and microbiological surveillance of IMD should integrate clinical and laboratory components, including molecular and genetic characterization, to enrich the dynamic understanding of the clinical evolution of IMD.

Deep immunophenotyping reveals biomarkers of multisystemic inflammatory syndrome in children in a Latin American cohort.

BACKGROUND: Multisystemic inflammatory syndrome in children (MIS-C) is a life-threatening disease that occurs 2-5 weeks after severe acute respiratory syndrome coronavirus 2 exposure and is characterized by severe multisystemic inflammation. Early recognition of MIS-C is key to prognosis; therefore, establishing clinical and laboratory biomarkers that predict complications is urgently needed. OBJECTIVE: We characterized the immune response and clinical features of patients with acute MIS-C and determined biomarkers of disease in a cohort of 42 Latin American patients. METHODS: Immune characterization was performed using flow cytometry from peripheral mononuclear cells and severe acute respiratory syndrome coronavirus 2-specific humoral and cellular response was performed using flow cytometry, enzyme-linked immunospot, enzyme-linked immunosorbent assay, and neutralizing antibody assays. RESULTS: MIS-C is characterized by robust T-cell activation and cytokine storm. We uncovered that while C-X-C motif chemokine ligand (CXCL) 9, IL-10, CXCL8, CXCL10, IL-6, and IL-18 are significantly elevated in patients with shock, while CCL5 was increased in milder disease. Monocyte dysregulation was specifically associated with KD-like MIS-C. Interestingly, MIS-C patients show a natural killer cell degranulation defect that is persistent after 6 months of disease presentation, suggesting it could underlie disease susceptibility. Most MIS-C had gastrointestinal involvement, and higher levels of neopterin were identified in their stools, potentially representing a biomarker of intestinal inflammation in MIS-C. Severe acute respiratory syndrome coronavirus 2-specific cellular response and neutralizing antibodies were identifiable in convalescent MIS-C patients, suggesting sustained immunity. CONCLUSION: Clinical characterization and comprehensive immunophenotyping of Chilean MIS-C cohort provide valuable insights in understanding immune dysregulation in MIS-C and identify relevant biomarkers of disease that could be used to predict severity and organ involvement.

[Recommendations for the diagnosis and treatment of urinary tract infection in pediatrics. Part 2: Working group associated with the Antimicrobial Committee, Chilean Society of Infectology]. / Recomendaciones para diagnóstico y tratamiento de la infección del tracto urinario en pediatría. Parte 2: Grupo de trabajo asociado al Comité de Antimicrobianos, Sociedad Chilena de Infectología (SOCHINF).

The urinary tract infection (UTI) is one of the most common bacterial infections in childhood. An adequate diagnosis is essential to be able to carry out a rational, efficient and effective treatment, however, there is great heterogeneity in diagnostic methods, specifically in the study of antimicrobial susceptibility. The aim of these recommendations is to provide tools to homogenize the diagnosis criteria, susceptibility study and antimicrobial treatment of urinary tract infection in the pediatric population, with a rational use of antibiotics approach. In the first part, the recommendations regarding diagnosis were presented, such as sampling and cut-off points, as well as microbiological considerations for susceptibility study and management of UTI in pediatrics. This second part details the management of complications, UTI in special situations, and pharmacokinetic and pharmacodynamic considerations of antimicrobials to be prescribed in UTI.

[Recommendations for the diagnosis and treatment of urinary tract infection in pediatrics. Part 1: Working group associated with the Antimicrobial Committee, Chilean Society of Infectology]. / Recomendaciones para diagnóstico y tratamiento de la infección del tracto urinario en pediatría. Parte 1: Grupo de trabajo asociado al Comité de Antimicrobianos, Sociedad Chilena de Infectología (SOCHINF).

The urinary tract infection (UTI) is one of the most common bacterial infections in childhood. An adequate diagnosis is essential to be able to carry out a rational, efficient and effective treatment, however, there great heterogeneity in diagnostic methods, specifically in the study of antimicrobial susceptibility. The aim of these recommendations is to provide tools to homogenize the diagnosis criteria, susceptibility study and antimicrobial treatment of urinary tract infection in the pediatric population, with a rational use of antibiotics approach. In the first part, the recommendations regarding diagnosis are presented, such as sampling and cut-off points, as well as microbiological considerations for susceptibility study and management of UTI in pediatrics. The second part details the management of complications, UTI in special situations, and pharmacokinetic and pharmacodynamic considerations of antimicrobials to be prescribed in UTI.

FilmArray® Meningoencephalitis panel in the diagnosis of central nervous system infections: stewardship and cost analysis in a paediatric hospital in Chile.

BACKGROUND: Central nervous system (CNS) infection has been an ongoing concern in paediatrics. The FilmArray® Meningoencephalitis (FAME) panel has greater sensitivity in identifying the aetiology of CNS infections. This study's objective was to compare the aetiological identification and hospitalization costs among patients with suspected CNS infection before and after the use of FAME. METHODS: An analytical observational study was carried out using a retrospective cohort for the pre-intervention (pre-FAME use) period and a prospective cohort for the post-intervention (post-FAME use) period in children with suspected CNS infection. RESULTS: A total of 409 CSF samples were analysed, 297 pre-intervention and 112 post-intervention. In the pre-intervention period, a total of 85.5% of patients required hospitalization, and in the post-intervention period 92.7% required hospitalization (p < 0.05). Median of ICU days was significantly lower in the post-intervention period than it was in the pre-intervention period. The overall positivity was 9.4 and 26.8%, respectively (p < 0.001). At ages 6 months and below, we found an increase in overall positivity from 2.6 to 28.1%, along with an increased detection of viral agents, S. agalactiae, S. pneumoniae, and N. meningitidis. The use of this diagnostic technology saved between $2916 and $12,240 USD in the cost of ICU bed-days. FAME use provided the opportunity for more accurate aetiological diagnosis of the infections and thus the provision of adequate appropriate treatment. CONCLUSIONS: The cost/benefit ratio between FAME cost and ICU bed-day cost savings is favourable. Implementation of FAME in Chilean public hospitals saves public resources and improves the accuracy of aetiological diagnosis.

Recomendaciones para diagnóstico y tratamiento de la infección del tracto urinario en pediatría. Parte 1: Grupo de trabajo asociado al Comité de Antimicrobianos, Sociedad Chilena de Infectología (SOCHINF) / Recommendations for the diagnosis and treatment of urinary tract infection in pediatrics. Part 1: Working group associated with the Antimicrobial Committee, Chilean Society of Infectology

Resumen La infección del tracto urinario (ITU) es una de las infecciones bacterianas más frecuentes en la infancia. Un adecuado diagnóstico es esencial para poder realizar un tratamiento racional, eficiente y eficaz; sin embargo, existe gran heterogeneidad en los métodos diagnósticos, específicamente en el estudio de la susceptibilidad antimicrobiana. El objetivo de estas recomendaciones es entregar herramientas para uniformar los criterios diagnósticos, el estudio de susceptibilidad bacteriana in vitro y el tratamiento antimicrobiano de la ITU en la población pediátrica, con un enfoque de uso racional de los antimicrobianos. En esta primera parte, se presentan las recomendaciones en cuanto a cómo obtener una adecuada muestra de orina, el diagnóstico de laboratorio incluyendo puntos de corte -unidades formadoras de colonias/mL de orina-, además de consideraciones microbiológicas para el estudio de susceptibilidad y finalmente, el manejo de la ITU en pediatría. En la segunda parte se detalla el tratamiento antimicrobiano de sus complicaciones, el manejo de ITU en situaciones especiales y consideraciones farmacocinéticas y farmacodinámicas de los antimicrobianos a indicar en ITU.

Abstract The urinary tract infection (UTI) is one of the most common bacterial infections in childhood. An adequate diagnosis is essential to be able to carry out a rational, efficient and effective treatment, however, there great heterogeneity in diagnostic methods, specifically in the study of antimicrobial susceptibility. The aim of these recommendations is to provide tools to homogenize the diagnosis criteria, susceptibility study and antimicrobial treatment of urinary tract infection in the pediatric population, with a rational use of antibiotics approach. In the first part, the recommendations regarding diagnosis are presented, such as sampling and cut-off points, as well as microbiological considerations for susceptibility study and management of UTI in pediatrics. The second part details the management of complications, UTI in special situations, and pharmacokinetic and pharmacodynamic considerations of antimicrobials to be prescribed in UTI.

[Panton-Valentine leukocidin toxin associated methicillin-susceptible Staphylococcus aureus infection: a report of two pediatric cases]. / Staphylococcus aureus sensible a meticilina, productor de leucocidina de Panton Valentine. A propósito de dos casos pediátricos de infección osteoarticular.

Staphylococcus aureus colonizes the nasopharynx in one third of healthy individuals and is also responsible for several infections in pediatrics such as endocarditis, pneumonia and osteoarticular infections. It has several virulence mechanisms, such as Panton Valentine leukocidin (PVL), which is an exotoxin that causes cell death. It is commonly related to methicillin-resistant Staphylococcus aureus (MRSA) and more serious pulmonary and musculoskeletal infections. However, PVL is not exclusive to MRSA. Two clinical cases of patients with infection by methicillin-sensitive Staphylococcus aureus producing this exotoxin are presented.

Staphylococcus aureus sensible a meticilina, productor de leucocidina de Panton Valentine: a propósito de dos casos pediátricos de infección osteoarticular / Panton-Valentine leukocidin toxin associated methicillin-susceptible Staphylococcus aureus infection: a report of two pediatric cases

Resumen Staphylococcus aureus coloniza la nasofaringe en un tercio de los individuos sanos y además es causante de infecciones graves en pediatría, como endocarditis, neumonía e infecciones osteoarticulares. Posee varios mecanismos de virulencia, siendo la leucocidina de Panton Valentine (LPV) uno de ellos, una exotoxina que causa muerte celular. Su producción está comúnmente relacionada con Staphylococcus aureus resistente a meticilina (SARM) e infecciones pulmonares y musculo-esqueléticas graves. Sin embargo, la producción de LPV no es exclusiva de SARM. Se presentan dos casos clínicos de pacientes con infección por Staphylococcus aureus sensible a meticilina productora de esta exotoxina.

Abstract Staphylococcus aureus colonizes the nasopharynx in one third of healthy individuals and is also responsible for several infections in pediatrics such as endocarditis, pneumonia and osteoarticular infections. It has several virulence mechanisms, such as Panton Valentine leukocidin (PVL), which is an exotoxin that causes cell death. It is commonly related to methicillin-resistant Staphylococcus aureus (MRSA) and more serious pulmonary and musculoskeletal infections. However, PVL is not exclusive to MRSA. Two clinical cases of patients with infection by methicillin-sensitive Staphylococcus aureus producing this exotoxin are presented.

A prospective, multi-center study of Candida bloodstream infections in Chile.

BACKGROUND: Active surveillance is necessary for improving the management and outcome of patients with candidemia. The aim of this study was to describe epidemiologic and clinical features of candidemia in children and adults in tertiary level hospitals in Chile. METHODS: We conducted a prospective, multicenter, laboratory-based survey study of candidemia in 26 tertiary care hospitals in Chile, from January 2013 to October 2017. RESULTS: A total of 780 episodes of candidemia were included, with a median incidence of 0.47/1,000 admissions. Demographic, clinical and microbiological information of 384 cases of candidemia, from 18 hospitals (7,416 beds), was included in this report. One hundred and thirty-four episodes (35%) occurred in pediatric patients and 250 (65%) in adult population. Candida albicans (39%), Candida parapsilosis (30%) and Candida glabrata (10%) were the leading species, with a significant difference in the distribution of species between ages. The use of central venous catheter and antibiotics were the most frequent risk factors in all age groups (> 70%). Three hundred and fifteen strains were studied for antifungal susceptibility; 21 strains (6.6%) were resistant to fluconazole, itraconazole, voriconazole, anidulafungin or micafungin. The most commonly used antifungal therapies were fluconazole (39%) and echinocandins (36%). The overall 30-day survival was 74.2%, significantly higher in infants (82%) and children (86%) compared with neonates (72%), adults (71%) and elderly (70%). CONCLUSIONS: Our prospective, multicenter surveillance study showed a low incidence of candidemia in Chile, with high 30-day survival, a large proportion of elderly patients, C. glabrata as the third most commonly identified strain, a 6.6% resistance to antifungal agents and a frequent use of echinocandins.

Susceptibilidad de enterobacterias a piperacilina/tazobactam en un hospital pediátrico de Chile / Enterobacteriaceae susceptibility to piperacillin/tazobactam in a Chilean pediatric hospital

Resumen Introducción: Las enterobacterias son bacilos gram-negativos responsables de infecciones graves en el ser humano. Se reporta una susceptibilidad en Klebsiella pneumoniae de 79,4% a piperacilina/tazobactam (PIP/TAZO) en hospitales pediátricos de Chile, pero según nuestro conocimiento, no existen datos publicados a la fecha respecto a la susceptibilidad de otras enterobacterias a PIP/TAZO en la población pediátrica chilena. Objetivo: Determinar la susceptibilidad in vitro a PIP/TAZO en cepas obtenidas de infecciones por Enterobacteriaceae en un hospital pediátrico de Chile. Material y Método: Estudio descriptivo y prospectivo de cepas de Enterobacteriaceae en Hospital de Niños Roberto del Río (HRRIO) entre 1 de enero de 2013 y el 27 de agosto de 2014. Se definió la susceptibilidad a PIP/TAZO por método de gradiente (E-test®) según puntos de corte CLSI 2014. Resultados: Se incluyeron 163 casos. El promedio de edad fue de 4 años 15 días. 70,6% de sexo femenino. El 79,7% de las cepas fueron aisladas en urocultivos. La susceptibilidad de Enterobacteriaceae a PIP/TAZO fue 95,1% (n = 155). La susceptibilidad intermedia fue 1,8% (n = 3). Discusión: Los aislados estudiados presentan alta susceptibilidad a PIP/TAZO. Este hallazgo puede explicarse por la baja circulación de microrganismos productores de BLEE y el limitado uso de PIP/TAZO en esta población pediátrica.

Introduction: Enterobacteriaceae are a group of gram-negative rods that can cause serious infections in humans. A susceptibility in Klebsiella pneumoniae of 79.4% to piperacillin/tazobactam (PIP/TAZO) is reported in pediatric hospitals in Chile. There is no published data published to date regarding PIP/TAZO susceptibility to other Enterobacteriaceae species in this population. Aim: To measure the in vitro PIP/TAZO susceptibility in Enterobacteriaceae isolates from patients in a pediatric hospital in Chile. Methods: Descriptive and prospective study of Enterobacteriaceae positive cultures from patients assisting to the "Hospital de niños Roberto del Río" (HRRIO) between January 2013 and August 2014. PIP/TAZO susceptibility was established by gradient diffusion method (E-test®) according to the 2014 CLSI standards. Results: 163 cases were included. The average age was 4 years and 15 days. 70.6% were female. 79.7% of samples were urine cultures. PIP/TAZO susceptibility in Enterobacteriaceae was 95.1% (n = 155). The intermediate susceptibility was 1.8% (n = 3). Discussion: The isolates studied present high susceptibility to PIP/TAZO. This finding could be explained by the fact that this population has not been exposed to this antimicrobial therapy and also the low rates for ESBL in pediatric infections.

[Enterobacteriaceae susceptibility to piperacillin/tazobactam in a Chilean pediatric hospital]. / Susceptibilidad de enterobacterias a piperacilina/tazobactam en un hospital pediátrico de Chile.

INTRODUCTION: Enterobacteriaceae are a group of gram-negative rods that can cause serious infections in humans. A susceptibility in Klebsiella pneumoniae of 79.4% to piperacillin/tazobactam (PIP/TAZO) is reported in pediatric hospitals in Chile. There is no published data published to date regarding PIP/TAZO susceptibility to other Enterobacteriaceae species in this population. AIM: To measure the in vitro PIP/TAZO susceptibility in Enterobacteriaceae isolates from patients in a pediatric hospital in Chile. METHODS: Descriptive and prospective study of Enterobacteriaceae positive cultures from patients assisting to the "Hospital de niños Roberto del Río" (HRRIO) between January 2013 and August 2014. PIP/TAZO susceptibility was established by gradient diffusion method (E-test®) according to the 2014 CLSI standards. RESULTS: 163 cases were included. The average age was 4 years and 15 days. 70.6% were female. 79.7% of samples were urine cultures. PIP/TAZO susceptibility in Enterobacteriaceae was 95.1% (n = 155). The intermediate susceptibility was 1.8% (n = 3). DISCUSSION: The isolates studied present high susceptibility to PIP/TAZO. This finding could be explained by the fact that this population has not been exposed to this antimicrobial therapy and also the low rates for ESBL in pediatric infections.

Infecciones respiratorias agudas bajas: descripción de los egresos del hospital Roberto del Río en el año 2016 / Acute respiratory infections low: description of the discharges of the hospital Roberto del Río in 2016

Las infecciones respiratorias agudas bajas (IRAB) son la principal causa de hospitalización en lactantes, y una de las principales causas de muerte de niños entre un mes y 4 años. Constituyen un problema de salud pública durante los meses de otoño e invierno, con una sobredemanda de atención en los servicios de urgencia y requerimiento de camas en los distintos centros hospitalarios, guardando este fenómeno directa relación con la epidemia del virus respiratorio sincicial (VRS), el principal agente etiológicoi-ii. En los últimos años se han implementado una serie de medidas que han permitido desarrollar un mejor manejo de las IRAB, como el uso de nuevos esquemas de vacunación, la disminución del uso irracional de antibióticos, la implementación de salas IRA en atención primaria para el manejo de las infecciones respiratoriasiii, uso de protocolos actualizados para manejo de patología respiratoriaiv, aumento del recurso humano durante la campaña de invierno en los servicios públicos de salud, y avances en infraestructura. Los virus son la principal causa de IRAB, siendo el VRS el más frecuente, seguido por rinovirus, virus influenza, parainfluenza, metapneumovirus, y adenovirus. Éste último, hasta hace algunos años era la segunda causa viral de IRAB, importante agente en infecciones asociadas a la atención en salud y causa de secuelas respiratorias en muchos casosv-vi. Esto pone de manifiesto la importancia de determinar la etiología de las IRAB en pacientes hospitalizados, más cuando la clínica e imagenología no permiten diferenciarlos. Conocer la etiología condicionará medidas terapéuticas a tomar, necesidad de aislamiento, y seguimiento de casos especiales. Esto cobra particular importancia en los lactantes, quienes por presentar un menor desarrollo de la vía respiratoria e inmadurez inmunológica, tienen las más altas tasas de hospitalización y padecen los cuadros más gravesvii. De acuerdo a datos del Departamento de Estadísticas e Información de Salud (DEIS) del año 2011, las infecciones respiratorias fueron la principal causa de egresos hospitalarios de niños y adolescentes en el país con un 21,7% del total. Específicamente en el Hospital Roberto del Rio la situación fue similar, correspondiendo a un 33,3% de las altas. En el siguiente reporte se describen las características de las infecciones respiratorias agudas bajas de niños y adolescentes egresados del Hospital Roberto del Río a lo largo del año 2016.

Lower respiratory tract infections (LRTI) are the main cause of outpatient visits during cold months and hospitalization in infants. Through an observational, descriptive study, we analyzed the medical attentions at the Emergency Department (ED) and the hospitalizations occurred during 2016 in Hospital Roberto del Río. We included demographic variables, date of admission, diagnosis at discharge, etiologic agent and requirement of intensive care unit. Respiratory infections were the main cause of outpatient visits to the ED, being 21.7%. They are also the major cause of hospital discharge (1,856 cases, 23.8% of total). 61% of hospitalized cases were male, ant the mail affected group was those under 2 years of age (74.4%). In 93% of cases with detected etiological agent, a virus was found, 57, 9% being respiratory syncytial virus. Sixty nine percent of admission occurred during June and September and 15, 2% patients were admitted to the intensive care unit. We hope the current data helps policy maker in further years.

Diagnóstico de patógenos respiratorios mediante PCR en tiempo real: una realidad en el Hospital Roberto del Río / Diagnosis of respiratory pathogens using real-time PCR: a reality at the Roberto del Río Hospital

La técnica de la reacción de polimerasa en cadena (PCR) en tiempo real o PCR está disponible en el Hospital Roberto del Río desde el 2015. Esta técnica rápida y muy sensible, mejora los tiempos de respuesta y facilita la toma de decisiones clínicas. Sin embargo, es importante conocer los distintos aspectos del método para hacer una correcta interpretación clínica de un resultado de PCR.

Real time polymerase chain reaction (PCR) is a rapid and sensitive technique. It improves answer time for clinical decisions. It is important to know it well for a better clinical understanding.

Potential effectiveness of copper surfaces in reducing health care-associated infection rates in a pediatric intensive and intermediate care unit: A nonrandomized controlled trial.

BACKGROUND: Studies have consistently shown that copper alloyed surfaces decrease the burden of microorganisms in health care environments. This study assessed whether copper alloy surfaces decreased hospital-associated infections in pediatric intensive and intermediate care units. METHODS: Admitted infants were assigned sequentially to a room furnished with or without a limited number of copper alloyed surfaces. Clinical and exposure to intervention data were collected on a daily basis. To avoid counting infections present prior to admission, patients who stayed in the hospital <72 hours were excluded from analysis. Health care-associated infections (HAIs) were confirmed according to protocol definitions. RESULTS: Clinical outcomes from 515 patients were considered in our analysis: 261 patients from the intervention arm of the study, and 254 from the control arm. Crude analysis showed an HAI rate of 10.6 versus 13.0 per 1,000 patient days for copper- and non-copper-exposed patients, respectively, for a crude relative risk reduction (RRR) of 0.19 (90% confidence interval, 0.46 to -0.22). Conducting clinical trials to assess interventions that may impact HAI rates is very challenging. The results here contribute to our understanding and ability to estimate the effect size that copper alloy surfaces have on HAI acquisition. CONCLUSIONS: Exposure of pediatric patients to copper-surfaced objects in the closed environment of the intensive care unit resulted in decreased HAI rates when compared with noncopper exposure; however, the RRR was not statistically significant. The clinical effect size warrants further consideration of this intervention as a component of a systems-based approach to control HAIs.

[Aspergillus fumigatus mediastinitis in an immunocompetent pediatric patient after heart surgery]. / Mediastinitis por Aspergillus fumigatus en un paciente pediátrico inmunocompetente posterior a una cardiocirugía.

Postsurgical aspergillosis occurs primarily in immunocompetent patients whose main predisposing factor is the loss of skin and mucosal integrity during surgery. Local infection tends to be destructive and refractory to treatment and relapses are common. It is important to consider aspergillosis in the differential diagnosis of slowly progressive and destructive surgical site infections with negative bacterial cultures. We present the case of a child who developed Aspergillus fumigatus mediastinitis months after heart surgery.

Novel nonsense mutation in the katA gene of a catalase-negative Staphylococcus aureus strain

Abstract We report the first description of a rare catalase-negative strain of Staphylococcus aureus in Chile. This new variant was isolated from blood and synovial tissue samples of a pediatric patient. Sequencing analysis revealed that this catalase-negative strain is related to ST10 strain, which has earlier been described in relation to S. aureus carriers. Interestingly, sequence analysis of the catalase gene katA revealed presence of a novel nonsense mutation that causes premature translational truncation of the C-terminus of the enzyme leading to a loss of 222 amino acids. Our study suggests that loss of catalase activity in this rare catalase-negative Chilean strain is due to this novel nonsense mutation in the katA gene, which truncates the enzyme to just 283 amino acids.

Novel nonsense mutation in the katA gene of a catalase-negative Staphylococcus aureus strain.

We report the first description of a rare catalase-negative strain of Staphylococcus aureus in Chile. This new variant was isolated from blood and synovial tissue samples of a pediatric patient. Sequencing analysis revealed that this catalase-negative strain is related to ST10 strain, which has earlier been described in relation to S. aureus carriers. Interestingly, sequence analysis of the catalase gene katA revealed presence of a novel nonsense mutation that causes premature translational truncation of the C-terminus of the enzyme leading to a loss of 222 amino acids. Our study suggests that loss of catalase activity in this rare catalase-negative Chilean strain is due to this novel nonsense mutation in the katA gene, which truncates the enzyme to just 283 amino acids.

Mediastinitis por Aspergillus fumigatus en un paciente pediátrico inmunocompetente posterior a una cardiocirugía / Aspergillus fumigatus mediastinitis in an immunocompetent pediatric patient after heart surgery

Postsurgical aspergillosis occurs primarily in immunocompetent patients whose main predisposing factor is the loss of skin and mucosal integrity during surgery. Local infection tends to be destructive and refractory to treatment and relapses are common. It is important to consider aspergillosis in the differential diagnosis of slowly progressive and destructive surgical site infections with negative bacterial cultures. We present the case of a child who developed Aspergillus fumigatus mediastinitis months after heart surgery.

Copper surfaces are associated with significantly lower concentrations of bacteria on selected surfaces within a pediatric intensive care unit.

BACKGROUND: Health care-associated infections result in significant patient morbidity and mortality. Although cleaning can remove pathogens present on hospital surfaces, those surfaces may be inadequately cleaned or recontaminated within minutes. Because of copper's inherent and continuous antimicrobial properties, copper surfaces offer a solution to complement cleaning. The objective of this study was to quantitatively assess the bacterial microbial burden coincident with an assessment of the ability of antimicrobial copper to limit the microbial burden associated with 3 surfaces in a pediatric intensive care unit. METHODS: A pragmatic trial was conducted enrolling 1,012 patients from 2 high acuity care units within a 249-bed tertiary care pediatric hospital over 12 months. The microbial burden was determined from 3 frequently encountered surfaces, regardless of room occupancy, twice monthly, from 16 rooms, 8 outfitted normally and 8 outfitted with antimicrobial copper. RESULTS: Copper surfaces were found to be equivalently antimicrobial in pediatric settings to activities reported for adult medical intensive care units. The log10 reduction to the microbial burden from antimicrobial copper surfaced bed rails was 1.996 (99%). Surprisingly, introduction of copper objects to 8 study rooms was found to suppress the microbial burden recovered from objects assessed in control rooms by log10 of 1.863 (73%). CONCLUSION: Copper surfaces warrant serious consideration when contemplating the introduction of no-touch disinfection technologies for reducing burden to limit acquisition of HAIs.

[Risk factor of intestinal colonization with vancomycin resistant Enterococcus spp in hospitalized pediatric patients with oncological disease]. / Factores de riesgo de colonización por Enterococcus spp resistente a vancomicina en pacientes pediátricos hospitalizados con patología oncológica.

BACKGROUND: The isolation of vancomycin-resistant Enterococcus spp (ERV) has increased significantly within the last few years, along with the risk of infection and dissemination of these bacteria. Our aim was to determine risk factors (RF) for intestinal colonization in hospitalized pediatric patients with oncological disease at Hospital de Niños Roberto del Río. METHODS: Between January 2012 and December 2013 a transversal study was performed with 107 rectal swabs and processed with a PCR for ERV. The patients were classified as "colonized with ERV" and "not colonized with ERV" and we evaluated possible RF for intestinal colonization in both groups. RESULTS: VRE colonization was found in 51 patients (52%). The median of time elapsed between oncological diagnosis and VRE colonization was 35 days. The significant RF associated with VRE colonization were days of hospitalization prior to study, neutropenia and treatment with antibiotics within 30 days prior to study and mucositis. CONCLUSIONS: According to the RF revealed in this study we may suggest prevention standards to avoid ERV colonization. This is the first investigation in our country in hospitalized pediatric patients with oncological disease and processed with a multiplex PCR for ERV, therefore it is a great contribution about this subject in Chile.