The Burkholderia contaminans prevalent phenotypes as possible markers of poor clinical outcomes in chronic lung infection of children with cystic fibrosis.

Burkholderia contaminans, a species of the Burkholderia cepacia complex-prevalent in certain Latin-American and European countries-can cause chronic pulmonary infection in persons with cystic fibrosis. Our aim was to gain insights into long-term lung infections with a focus on correlating how bacterial phenotypic traits in the chronic infection impact on patients' clinical outcome. Genotypic characteristics of 85 B. contaminans isolates recovered from 70 patients were investigated. For 16 of those patients, the clinical status and bacterial phenotypic characteristics, e.g. several virulence factors, phenotypic variants, and the antimicrobial susceptibility pattern, were evaluated. Two clones were found in the whole bacterial population: (i) the multiresistant ST 872 PCR-recA-RFLP-HaeIII-K-pattern clone, which carries a pathogenic island homologous to BcenGI11 of B. cenocepacia J2315, and (ii) the ST 102 PCR-recA-RFLP-HaeIII-AT-pattern clone. The emergence of certain bacterial phenotypes in the chronic infection such as the nonmucoid phenotype, small colony variants, brownish pigmented colonies, and hypermutators, proved to be, together with coinfection with Pseudomonas aeruginosa, the possible markers of more challenging infections and poor prognosis. The presence of cocolonizers and the bacterial phenotypes that are especially adapted to persist in long-term respiratory tract infections have a crucial role in patients' clinical outcomes.

Estudio multicéntrico argentino sobre la utilidad del panel de neumonía de FilmArray® / Argentine multicenter study on the utility of the FilmArray® pneumonia panel

Resumen Las infecciones de las vías respiratorias inferiores se encuentran entre aquellas en las que el uso inadecuado de antimicrobianos es frecuente, por lo que es fundamental contar con una prueba diagnóstica rápida, sensible y específica. El sistema de FilmArray es un análisis de PCR múltiple con un panel de neumonía que incluye 26 microorganismos y 7 marcadores de resistencia antimicrobiana. Los objetivos de este estudio fueron: a) establecer la correlación entre los cultivos cuantitativos para agentes bacterianos de muestras de vías respiratorias inferiores (MRVB) y la detección fenotípica de mecanismos de resistencia con los correspondientes resultados de FilmArray; b) determinar el cambio terapéutico generado con el informe del resultado inmediato. Se incluyó un total de 194 MRVB correspondientes a 191 pacientes con neumonía y se documentaron 277 bacterias. FilmArray identificó 253/277 (91%) bacterias y 161/277 (58%) se aislaron del cultivo, 58 (23%) coincidieron con el mismo recuento, 116 (46,7%) dieron mayores recuentos con FilmArray y 72 (28,9%) fueron detectadas por este método pero el cultivo fue negativo. Se detectaron marcadores de resistencia antimicrobiana en 63 aislados, pero solo 28 fueron confirmados por métodos fenotípicos. Estos resultados podrían haber provocado cambios en el tratamiento antibiótico en el 74,6% (174/194). FilmArray es una herramienta útil para optimizar el tratamiento antimicrobiano en pacientes con neumonía.

Abstract Lower respiratory tract infections are among those in which the inappropriate use of antimicrobials is common, so it is essential to have a rapid, sensitive and specific diagnostic test. The FilmArray system is a multiplex PCR assay with a pneumonia panel that includes 26 microorganisms and 7 antibiotic resistance markers. The objectives of this study were: a) to establish the correlation between quantitative cultures for bacterial agents from lower respiratory tract samples (MRVB) and the phenotypic detection of resistance mechanisms with the corresponding results of FilmArray b) to determine the therapeutic change generated with the immediate result report. A total of 194 MRVB corresponding to 191 patients with pneumonia were included and 277 bacterial strains were documented. FilmArray identified 253/277 (91%) bacteria and 161/277 (58%) were isolated from culture, 58 (23%) matched the same count, 116 (46.7%) yielded higher counts with FilmArray, and 72 (28.9%) with negative culture were detected by this method. Antibiotic resistance markers were detected in 63 strains, but only 28 were confirmed by phenotypic methods. These results may cause changes in the antimicrobial treatment in 74.6% (174/194). FilmArray is a useful tool to optimize antimicrobial therapy in patients with pneumonia.

Resumo As infecções do trato respiratório inferior estão entre aquelas em que o uso inadequado de antimicrobianos é comum, por isso é essencial um teste diagnóstico rápido, sensível e específico. O sistema FilmArray é um ensaio de PCR multiplo com um painel de pneumonia que inclui 26 microrganismos e 7 marcadores de resistência antimicrobiana. Os objetivos deste estudo foram: a) estabelecer a correlação entre as culturas quantitativas de agentes bacterianos de amostras do trato respiratório inferior (MRVB) e a detecção fenotípica de mecanismos de resistência com os resultados correspondentes do FilmArray b) determinar a alteração terapêutica gerada com o relatório de resultado imediato. Um total de 194 MRVB correspondendo a 191 pacientes com pneumonia foram incluídos e 277 cepas bacterianas foram documentadas. FilmArray identificou 253/277 (91%) bactérias e 161/277 (58%) foram isoladas da cultura, 58 (23%) coincidiram com mesma contagem, 116 (46,7%) deram contagens mais altas com FilmArray e 72 (28,9%) foram detectados por este método, mas a cultura foi negativa. Marcadores de resistência antimicrobiana foram detectados em 63 cepas, mas apenas 28 foram confirmados por métodos fenotípicos. Esses resultados puderam causar alterações no tratamento antibiótico em 74,6% (174/194). FilmArray é uma ferramenta útil para otimizar a terapia antimicrobiana em pacientes com pneumonia..

Novel Guanidine Compound against Multidrug-Resistant Cystic Fibrosis-Associated Bacterial Species.

Chronic pulmonary infection is a hallmark of lung disease in cystic fibrosis (CF). Infections dominated by non-fermentative Gram-negative bacilli are particularly difficult to treat and highlight an urgent need for the development of new class of agents to combat these infections. In this work, a small library comprising thiourea and guanidine derivatives with low molecular weight was designed; these derivatives were studied as antimicrobial agents against Gram-positive, Gram-negative, and a panel of drug-resistant clinical isolates recovered from patients with CF. One novel compound, a guanidine derivative bearing adamantane-1-carbonyl and 2-bromo-4,6-difluouro-phenyl substituents (H-BDF), showed potent bactericidal activity against the strains tested, at levels generally higher than those exhibited by tobramycin, ceftazimide and meropenem. The role that different substituents exert in the antimicrobial activity has been determined, highlighting the importance of the halo-phenyl group in the guanidine moiety. The new compound displays low levels of cytotoxicity against THP-1 and A549 cells with a selective index (SI) > 8 (patent application PCT/IB2017/054870, August 2017). Taken together, our results indicate that H-BDF can be considered as a promising antimicrobial agent.

Burkholderia puraquae sp. nov., a novel species of the Burkholderia cepacia complex isolated from hospital settings and agricultural soils.

Bacteria from the Burkholderia cepacia complex (Bcc) are capable of causing severe infections in patients with cystic fibrosis (CF). These opportunistic pathogens are also widely distributed in natural and man-made environments. After a 12-year epidemiological surveillance involving Bcc bacteria from respiratory secretions of Argentinean patients with CF and from hospital settings, we found six isolates of the Bcc with a concatenated species-specific allele sequence that differed by more than 3 % from those of the Bcc with validly published names. According to the multilocus sequence analysis (MLSA), these isolates clustered with the agricultural soil strain, Burkholderia sp. PBP 78, which was already deposited in the PubMLST database. The isolates were examined using a polyphasic approach, which included 16S rRNA, recA, Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), DNA base composition, average nucleotide identities (ANIs), fatty acid profiles, and biochemical characterizations. The results of the present study demonstrate that the seven isolates represent a single novel species within the Bcc, for which the name Burkholderia puraquae sp. nov. is proposed. Burkholderia puraquae sp. nov. CAMPA 1040T (=LMG 29660T=DSM 103137T) was designated the type strain of the novel species, which can be differentiated from other species of the Bcc mainly from recA gene sequence analysis, MLSA, ANIb, MALDI-TOF MS analysis, and some biochemical tests, including the ability to grow at 42 °C, aesculin hydrolysis, and lysine decarboxylase and ß-galactosidase activities.

First time identification of Pandoraea sputorum from a patient with cystic fibrosis in Argentina: a case report.

BACKGROUND: Pandoraea species are considered emerging pathogens in the context of cystic fibrosis (CF) and are difficult to identify by conventional biochemical methods. These multidrug resistant bacteria remain poorly understood particularly in terms of natural resistance, mechanisms of acquired resistance and impact on the prognosis of the disease and the lung function. Among them, Pandoraea sputorum has been previously described in few cases of CF patients from Spain, Australia, France and United States, underlining the need of more clinical data for a better knowledge of its pathogenicity. This is the first report relating to P. sputorum in a CF patient in Argentina. CASE PRESENTATION: Pandoraea sputorum was identified in a nine-year-old cystic fibrosis patient from Argentina, after treatment failure during an exacerbation. The isolates were successfully identified by combining molecular techniques based on 16S rRNA sequencing and mass spectrometry (MS) methods, after reassessing previous misidentified isolates by conventional methods. After first isolation of P. sputorum, patient's clinical condition worsened but later improved after a change in the treatment. Although isolates showed susceptibility to trimethoprim-sulfamethoxazole and imipenem, in our case, the antibiotic treatment failed in the eradication of P. sputorum. CONCLUSIONS: All combined data showed a chronic colonization with P. sputorum associated to a deterioration of lung function. We noted that the presence of P. sputorum can be underestimated in CF patients and MALDI-TOF MS appears to be a promising means of accurate identification of Pandoraea species.

Cystic Fibrosis Cloud database: Un sistema informático para el almacenamiento y manejo de datos clínicos y microbiológicos del paciente con fibrosis quística / Cystic Fibrosis Cloud database: An information system for storage and management of clinical and microbiological data of cystic fibrosis patients

El manejo clínico y epidemiológico de los pacientes con fibrosis quística (FQ) con exacerbaciones pulmonares agudas o infecciones pulmonares crónicas demanda una actualización permanente de procedimientos médicos y microbiológicos, estos se asocian con la constante evolución de los agentes patógenos durante la colonización de su hospedador. Para poder monitorear la dinámica de estos procesos es fundamental disponer de sistemas expertos que permitan almacenar, extraer y utilizar la información generada a partir de estudios realizados sobre el paciente y los microorganismos aislados de aquel. En este trabajo hemos diseñado y desarrollado una base de datos on-line basada en un sistema informático que permite el almacenamiento, el manejo y la visualización de la información proveniente de estudios clínicos y de análisis microbiológicos de bacterias obtenidas del tracto respiratorio del paciente con FQ. Este sistema informático fue designado como Cystic Fibrosis Cloud database (CFC database) y está disponible en el sitio http://servoy.infocomsa.com/cfc_database. Está compuesto por una base de datos principal y una interfaz on-line, la cual emplea la arquitectura de productos Servoy basada en tecnología Java. Si bien el sistema CFC database puede ser implementado como un programa local de uso privado en los centros de asistencia a pacientes con FQ, admite también la posibilidad de ser empleado, actualizado y compartido por diferentes usuarios, quienes pueden acceder a la información almacenada de manera ordenada, práctica y segura. La implementación del CFC database podría tener una gran impacto en la monitorización de las infecciones respiratorias, la prevención de exacerbaciones, la detección de organismos emergentes y la adecuación de las estrategias de control de infecciones pulmonares en pacientes con FQ

The epidemiological and clinical management of cystic fibrosis (CF) patients suffering from acute pulmonary exacerbations or chronic lung infections demands continuous updating of medical and microbiological processes associated with the constant evolution of pathogens during host colonization. In order to monitor the dynamics of these processes, it is essential to have expert systems capable of storing and subsequently extracting the information generated from different studies of the patients and microorganisms isolated from them. In this work we have designed and developed an on-line database based on an information system that allows to store, manage and visualize data from clinical studies and microbiological analysis of bacteria obtained from the respiratory tract of patients suffering from cystic fibrosis. The information system, named Cystic Fibrosis Cloud database is available on the http://servoy.infocomsa.com/cfc_database site and is composed of a main database and a web-based interface, which uses Servoy's product architecture based on Java technology. Although the CFC database system can be implemented as a local program for private use in CF centers, it can also be used, updated and shared by different users who can access the stored information in a systematic, practical and safe manner. The implementation of the CFC database could have a significant impact on the monitoring of respiratory infections, the prevention of exacerbations, the detection of emerging organisms, and the adequacy of control strategies for lung infections in CF patients

[Cystic Fibrosis Cloud database: An information system for storage and management of clinical and microbiological data of cystic fibrosis patients]. / Cystic Fibrosis Cloud database: Un sistema informático para el almacenamiento y manejo de datos clínicos y microbiológicos del paciente con fibrosis quística.

The epidemiological and clinical management of cystic fibrosis (CF) patients suffering from acute pulmonary exacerbations or chronic lung infections demands continuous updating of medical and microbiological processes associated with the constant evolution of pathogens during host colonization. In order to monitor the dynamics of these processes, it is essential to have expert systems capable of storing and subsequently extracting the information generated from different studies of the patients and microorganisms isolated from them. In this work we have designed and developed an on-line database based on an information system that allows to store, manage and visualize data from clinical studies and microbiological analysis of bacteria obtained from the respiratory tract of patients suffering from cystic fibrosis. The information system, named Cystic Fibrosis Cloud database is available on the http://servoy.infocomsa.com/cfc_database site and is composed of a main database and a web-based interface, which uses Servoy's product architecture based on Java technology. Although the CFC database system can be implemented as a local program for private use in CF centers, it can also be used, updated and shared by different users who can access the stored information in a systematic, practical and safe manner. The implementation of the CFC database could have a significant impact on the monitoring of respiratory infections, the prevention of exacerbations, the detection of emerging organisms, and the adequacy of control strategies for lung infections in CF patients.

A cultivation-independent PCR-RFLP assay targeting oprF gene for detection and identification of Pseudomonas spp. in samples from fibrocystic pediatric patients.

Species-specific genetic markers are crucial to develop faithful and sensitive molecular methods for the detection and identification of Pseudomonas aeruginosa (Pa). We have previously set up a PCR-RFLP protocol targeting oprF, the gene encoding the genus-specific outer membrane porin F, whose strong conservation and marked sequence diversity allowed detection and differentiation of environmental isolates (Agaras et al., 2012). Here, we evaluated the ability of the PCR-RFLP assay to genotype clinical isolates previously identified as Pa by conventional microbiological methods within a collection of 62 presumptive Pa isolates from different pediatric clinical samples and different sections of the Hospital de Niños "Sor María Ludovica" from La Plata, Argentina. All isolates, but one, gave an oprF amplicon consistent with that from reference Pa strains. The sequence of the smaller-sized amplicon revealed that the isolate was in fact a mendocina Pseudomonas strain. The oprF RFLP pattern generated with TaqI or HaeIII nucleases matched those of reference Pa strains for 59 isolates (96%). The other two Pa isolates (4%) revealed a different RFLP pattern based on HaeIII digestion, although oprF sequencing confirmed that Pa identification was correct. We next tested the effectiveness of the PCR-RFLP to detect pseudomonads on clinical samples of pediatric fibrocystic patients directly without sample cultivation. The expected amplicon and its cognate RFLP profile were obtained for all samples in which Pa was previously detected by cultivation-dependent methods. Altogether, these results provide the basis for the application of the oprF PCR-RFLP protocol to directly detect and identify Pa and other non-Pa pseudomonads in fibrocystic clinical samples.

Hypermutation in Burkholderia cepacia complex is mediated by DNA mismatch repair inactivation and is highly prevalent in cystic fibrosis chronic respiratory infection.

The Burkholderia cepacia complex (Bcc) represents an important group of pathogens involved in long-term lung infection in cystic fibrosis (CF) patients. A positive selection of hypermutators, linked to antimicrobial resistance development, has been previously reported for Pseudomonas aeruginosa in this chronic infection setting. Hypermutability, however, has not yet been systematically evaluated in Bcc species. A total of 125 well characterized Bcc isolates recovered from 48 CF patients, 10 non-CF patients and 15 environmental samples were analyzed. In order to determine the prevalence of mutators their spontaneous mutation rates to rifampicin resistance were determined. In addition, the genetic basis of the mutator phenotypes was investigated by sequencing the mutS and mutL genes, the main components of the mismatch repair system (MRS). The overall prevalence of hypermutators in the collection analyzed was 13.6%, with highest occurrence (40.7%) among the chronically infected CF patients, belonging mainly to B. cenocepacia, B. multivorans, B. cepacia, and B. contaminans -the most frequently recovered Bcc species from CF patients worldwide. Thirteen (76.5%) of the hypermutators were defective in mutS and/or mutL. Finally, searching for a possible association between antimicrobial resistance and hypermutability, the resistance-profiles to 17 antimicrobial agents was evaluated. High antimicrobial resistance rates were documented for all the Bcc species recovered from CF patients, but, except for ciprofloxacin, a significant association with hypermutation was not detected. In conclusion, in the present study we demonstrate for the first time that, MRS-deficient Bcc species mutators are highly prevalent and positively selected in CF chronic lung infections. Hypermutation therefore, might be playing a key role in increasing bacterial adaptability to the CF-airway environment, facilitating the persistence of chronic lung infections.

Genetic diversity of Burkholderia contaminans isolates from cystic fibrosis patients in Argentina.

A total of 120 Burkholderia cepacia complex isolates collected during 2004-2010 from 66 patients in two cystic fibrosis reference centers in Argentina were analyzed. Burkholderia contaminans was the species most frequently recovered (57.6%), followed by Burkholderia cenocepacia (15%), a species distribution not reported so far. The recA-PCR-based techniques applied to the B. contaminans isolates revealed that 85% of the population carried the recA-ST-71 allele. Our results showed the utility of BOX-PCR genotyping in analyzing B. contaminans diversity. This approach allowed us to address clonal transmission during an outbreak and the genetic changes occurring in infecting bacteria over the course of chronic infection.

Epidemiological study of shigellosis in an urban area of Argentina.

INTRODUCTION: Shigellosis represents one of the main causes of bloody diarrhoea in South America. This study aimed to establish the incidence of shigellosis in an urban zone of Buenos Aires, Argentina, by examining the type of Shigella and living conditions associated with this infection. METHODOLOGY: Between January 2009 and December 2010 we analyzed shigellosis in children admitted to the public health service with bloody diarrhoea from La Plata, the capital of Buenos Aires, Argentina. A total of 372 children under 15 years old with Shigella present in their stool samples were admitted to the study. Variables studied were patient age, type of Shigella, family economic status, and access to sewage services and safe drinking water. RESULTS: Shigella flexneri was found to be present in 66.8% of the cases. Incidence was 187 cases/year/100,000 children under 15 years old. Cases were mainly observed during the summer (38.5%) in the population of under 5 years old (69.1% of all cases). The risk of shigellosis increased 12 times in those children who lacked safe drinking water and this risk increased 1.5 times in the population without sewage services. Fewer cases of shigellosis were noted in downtown areas, while hot spots were identified in the suburbs. Treating one case of shigellosis has a local cost of US $976 while assuring safe drinking water and sewage services for one family costs US $634.  CONCLUSION: Incidence of shigellosis in urban areas is associated with quality of water and sewage services. Policies aimed at providing education and improving public utilities networks can help to reduce the incidence of shigellosis.

Evaluación de los sistemas comerciales automatizados VITEK 2 y API 20NE para la identificación de organismos del complejo Burkholderia cepacia aislados de muestras clínicas / Evaluation of commercial systems VITEK 2 and API 20NE for identification of Burkholderia cepacia complex bacteria from clinical samples

Las especies del complejo Burkholderia cepacia (CBC) son capaces de causar infecciones crónicas del tracto respiratorio en pacientes con fibrosis quística y en otros individuos inmunocomprometidos. La mayoría de estas especies exhiben alta resistencia a la terapia antibiótica, lo que genera la necesidad de una detección rápida y precisa para poder implementar estrategias de control adecuadas. En este trabajo se utilizó la técnica de reacción en cadena de la polimerasa (PCR) para amplificar el gen recA (PCR-recA), con el fin de identificar microorganismos pertenecientes al CBC. Con este método molecular como referencia, se evaluó la sensibilidad (S) y la especificidad (E) de dos sistemas de identificación comerciales automatizados, VITEK 2 y API 20NE (bioMérieux®), así como también el valor de las pruebas bioquímicas manuales más representativas para la identificación de estos microorganismos. El método VITEK 2 presentó una S del 71,1 % y una E del 100 %; para el método API 20NE, estos valores fueron 69,7 % y 90,2 %, respectivamente. En cuanto a las pruebas fenotípicas manuales, los resultados obtenidos fueron más heterogéneos, lo que posiblemente se deba a que estas bacterias podrían sufrir presión selectiva para sobrevivir en pacientes crónicos y perder factores fenotípicos característicos. La técnica de PCR-recA resultó de fácil implementación, por lo que cabe considerar a esta técnica de identificación como una opción viable, aun en laboratorios de diagnóstico clínico de mediana complejidad.

Species belonging to the Burkholderia cepacia complex (BCC) are capable of causing chronic respiratory tract infections in patients suffering from cystic fibrosis as wel as in immunocompromised individuals. Most of these species are highly resistant to antibiotic therapy, generating the need for their rapid and accurate detection for the proper treatment and clinical management of these patients. In this wok, the polymerase chain reaction (PCR) technique based on the amplification of the recA gene (PCR-recA) was applied for an accurate identification of bacteria belonging to the BCC. Sensitivity (S) and specificity (E) of two biochemically-based commercial automated systems, API 20NE and VITEK 2 (bioMérieux®), and of the most representative biochemical manual tests for the identification of the Burkholderia cepacia complex were herein evaluated. The commercial systems VITEK 2 and API 20NE showed the following sensitivity and specificity vaues for identification to the species level, S: 71.1 %, E: 100 %, S: 69.7 %, E: 90.2 %, respectively. More complex results were observed for phenotypic manual tests, since BCC bacteria can undergo selective pressure to survive in chronic patients causing the loss of their typical phenotypic characteristics. The PCR-recA technique was easy to implement even in medium-complexity clinical diagnostic laboratories.

[Evaluation of commercial systems VITEK 2 and API 20NE for identification of Burkholderia cepacia complex bacteria from clinical samples]. / Evaluación de los sistemas comerciales automatizados VITEK 2 y API 20NE para la identificación de organismos del complejo Burkholderia cepacia aislados de muestras clínicas.

Species belonging to the Burkholderia cepacia complex (BCC) are capable of causing chronic respiratory tract infections in patients suffering from cystic fibrosis as well as in immunocompromised individuals. Most of these species are highly resistant to antibiotic therapy, generating the need for their rapid and accurate detection for the proper treatment and clinical management of these patients. In this work, the polymerase chain reaction (PCR) technique based on the amplification of the recA gene (PCR-recA) was applied for an accurate identification of bacteria belonging to the BCC. Sensitivity (S) and specificity (E) of two biochemically-based commercial automated systems, API 20NE and VITEK 2 (bioMérieux®), and of the most representative biochemical manual tests for the identification of the Burkholderia cepacia complex were herein evaluated. The commercial systems VITEK 2 and API 20NE showed the following sensitivity and specificity vaues for identification to the species level, S: 71.1 %, E: 100 %, S: 69.7 %, E: 90.2 %, respectively. More complex results were observed for phenotypic manual tests, since BCC bacteria can undergo selective pressure to survive in chronic patients causing the loss of their typical phenotypic characteristics. The PCR-recA technique was easy to implement even in medium-complexity clinical diagnostic laboratories.

Analisis de la resistencia a los antibacterianos en los aislamientos de pacientes internados en el Hospital de Niños Superiora Sor María Ludovica durante el año 2005 / An analysis of the resistance to antibacterials in germs isolated from in patients at the Superiora Sor María Ludovica children's Hospital, 2005

El tratamiento empírico con antibióticos adecuados requiere del conocimiento de la epidemiología bacteriana local. Para ello se realizo un estudio retrospectivo de la sensibilidad a los antibióticos de los microorganismos recuperados durante 2005 de los pacientes internados.Los microorganismos mas frecuentemente aislados fueron: Staphylococcus aureus (S. aureus) (24.1 %), Escherichia coli (E. coli) (15.8 %), Klebsiella pneumoniae (K. Pneumoniae) (12.4%) y Pseudomonas aeruginosa (P. aeruginosa) (10.1 %). En S. aureus la resistencia a meticilina supero el 40 %, con alto porcentaje de resistencia acompañante a otros antibióticos y total sensibilidad a TMS. La resistencia en E. coli y K. pneumoniae a cefalosporinas de tercera generación llego a niveles alarmantes (34.1% y 60%, respectivamente). P. aeruginosa mostró altos niveles para ceftazidima, carbapenemes y gentamicina (entre el 10% y 20%), mantenido total sensibilidad al colistin.Resulta evidente que el control de la infección Hospitalaria y el uso racional de los antimicrobianos son las únicas alternativas para impedir el incremento de la residencia de las bacterias.

Estreptococo ß hemolítico grupo A en pacientes pediátricos: análisis de la sensibilidad a los macrólidos / Group A Beta hemolytic streptococcus in pediatrics: analysis of its sensitivity to macrolides

El streptococcus pyogenes (estreptococo beta hemolítico grupo A) (S. pyogenes) es el microorganismo aislado mas frecuentemente en la faringo amigdalitis bacteriana. No existen hasta el momento cepas resistentes a penicilina, por lo tanto sigue siendo el antibiótico de elección para su tratamiento. En los últimos años se ha detectado un aumento de la resistencia a antibióticos de la familia de los macrólidos, tanto en nuestro país como en el resto del mundo. Debido a esta realidad decidimos vigilar que ocurre con los aislamientos de S. pyogenes obtenidos de muestras de hisopados de fauces en nuestro hospital.Se estudiaron 152 cepas entre mayo de 2002 y mayo de 2006. El cultivo y la identificación bioquímica se realizaron por la metodología convencional. Las pruebas de sensibilidad se ensayaron de acuerdo a las normas CLSI (Clinical and Laboratory Standards Institute). Se realizo antibiograma por difusión en agar Mueller-Hinton con 5% de sangre ovina, probándose penicilina, eritromicina y clindamicina.Todos los aislamientos estudiados fueron sensibles a los antibióticos ensayados. Dado su bajo costo y su baja selección de resistencia en el resto de la flora oro-faríngia, la penicilina sigue siendo el antibiótico de elección para el tratamiento de las faringitis estreptocóccicas.

Diagnóstico del estado nutricional de micronutrientes y evaluación antropométrica en una población infantil suburbana de la Provincia de Buenos Aires / Diagnosis of micronutrient nutritional status and anthropometric in a suburban child population in the Province of Buenos Aires

Objetivo: Determinar el estado nutricional evaluado por antropometría, y el estado nutricional de micro nutrientes en una población infantil. Métodos: Se estudiaron 205 niños de 4 a 10 años de una comunidad suburbana de La Plata, Argentina. Se determino Peso/edad, Talla/edad y Peso/talla y se comparo las referencias. Para determinar las deficiencias de micro nutrientes y anemia se establecieron los siguientes puntos de cortes: Deficiencia de zinc y cobre < 70 mcg/dl (absorción atómica), hierro por ferritina < 12 ng/dl (quimioluminiscencia), hemoglobina < 11,5 g/dl (Coulter). Se realizó una encuesta social y de ingesta y de hábitos alimentarios. Los datos se analizaron con EpiInfo 6. Se utilizaron las correlaciones de Pearson y Spearman. Resultados: La media de edad fue de 6,69 (± 2,04), 46,6 % de sexo femenino. El número de integrantes de familia fue de 6 (± 1,98), la dieta cubría las recomendaciones de proteínas, pero el 19,4 % no cubría las recomendaciones de calorías y 30,33 y 40 % de los niños no cubrieron las recomendaciones de hierro, zinc y vitamina A respectivamente. La prevalencia de insuficiente progresión de peso fue 4,5 % (Store Z < -2 de P/E) y por < Percentilo 10 de P/E 19,2 %; retraso crónico de crecimiento (<-2 score Z T/E) fue 5,6 %, y 23,2 % (< percentilo 10); por el indicador P/T la emaciación de primer grado alcanzó el 5%, sobrepeso y la obesidad llegó al 17,7 %. La prevalencia de anemia fue 21,6 %. El 6,8 % de los niños presento deficiencia de hierro, 5,1 % deficiencia de cobre y 11,3 % deficiencia de zinc. No se halló correlación significativa entre Peso/edad, peso/talla y Talla/ edad, con los niveles séricos de micro nutrientes y Hb, ni al comparar el estado nutricional y la prevalencia de deficiencia de cada micro nutrientes, excepto la prevalencia deficiencia de hierro en niños con retraso crónico de merecimiento que fue mayor que en el resto de los niños (p: 0,01)...

Stenotrophomonas maltophilia, bacilo gram negativo no fermentador aislados de muestras clínicas de pacientes pediátricos / Stenotrophomas maltophilia gram negativ rod isloted ferment with nosocomial of patients infants

Stenotrophomonas maltophilia (SMA) es un bacilo gram negativo no fermentador que causa infecciones en pacientes con defensas disminuidas y/o instrumentados. Se realizó un análisis retrospectivo de los aislamientos obtenidos en el año 2003 en el laboratorio de Bacteriología del Hospital de Niños Sor María Ludovica. Se obtuvieron 64 aislamientos de los cuales 36 fueron de origen respiratorio y 24 de hemocultivos. Tanto su resistencia a carbapenemes como su sensibilidad a TMS son orientadores para su diagnóstico microbiológico. Este perfil asociado a resistencia a otros antibióticos suele plantear problemas terapéuticos severos