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Rapid diagnostic techniques are valuable tools in the diagnosis of gastrointestinal infections, especially for the detection of some microorganisms and in certain groups of patients. While antigen detection techniques are widely used in Clinical Microbiology laboratories, for the diagnosis of viruses, some parasites and some bacteria, molecular techniques are routinely used only for some pathogens (such as Clostridium difficile). However, molecular techniques are constantly evolving, and they allow a rapid diagnosis for an increasing number of pathogens, with high sensitivity and specificity. In addition, they are also able to detect virulence factors or resistance mechanisms. Syndromic surveillance systems, which detect different pathogens simultaneously, are very promising because they enable the most frequent pathogens to be diagnosed in a few hours and they can be very useful in certain patients. For the diagnosis of Helicobacter pylori infection, molecular techniques are able to detect bacteria and its resistance to clarithromycin and levofloxacin, allowing the most appropriate treatment to be selected for each patient when bacterial culture is not possible.
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Técnicas de Diagnóstico del Sistema Digestivo , Enfermedades Gastrointestinales/diagnóstico , Técnicas Bacteriológicas , Enfermedades Gastrointestinales/microbiología , Enfermedades Gastrointestinales/parasitología , Enfermedades Gastrointestinales/virología , Humanos , Técnicas Inmunológicas , Técnicas de Diagnóstico Molecular , Parasitología/métodos , Factores de Tiempo , Virología/métodos , Compuestos Orgánicos Volátiles/análisisRESUMEN
BACKGROUND: Achromobacter xylosoxidans is an emerging pathogen in cystic fibrosis (CF). Although the rate of colonization by this microorganism is variable, prevalence is increasing in CF units. METHODS: A microbiological/clinical study was conducted on of adult CF patients harboring A. xylosoxidans. Identification and susceptibility testing were performed using MicroScan (Siemens). Decline in lung function was assessed using the variable, annual percentage loss of FEV1 (forced expiratory volume in 1s). RESULTS: A. xylosoxidans was isolated in 18 (19.8%) of 91 patients over a 14-year period. Mean age was 26.6 years (18-39 years). Nine patients (9.8%) were chronically colonized. Piperacillin/tazobactam and imipenem were the most active antibiotics. Mean annual decline in lung function in chronically colonized patients was 2.49%. CONCLUSIONS: A. xylosoxidans is a major pathogen in CF. A decreased lung function was observed among patients who were chronically colonized by A. xylosoxidans. Antibiotic therapy should be started early in order to prevent chronic colonization by this microorganism.
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Achromobacter denitrificans/aislamiento & purificación , Fibrosis Quística/microbiología , Infecciones por Bacterias Gramnegativas/complicaciones , Adolescente , Adulto , Antibacterianos/uso terapéutico , Fibrosis Quística/tratamiento farmacológico , Femenino , Volumen Espiratorio Forzado , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Humanos , Masculino , Estudios Retrospectivos , Adulto JovenRESUMEN
Table S1 in the Supplementary Material (Phenolic compounds identified in yarrow samples by using HPLC-ESI-QTOF-MS) in the original paper [...].
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Franski and Beszterda-Buszczak [...].
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The main objective of this work is to evaluate the potential utility of an Achillea millefolium extract (yarrow extract, YE) in the control of H. pylori infection. The supercritical anti-solvent fractionation (SAF) process of YE allowed the obtaining of two different fractions: yarrow's precipitated fraction (YPF), enriched in most polar phenolic compounds (luteolin-7-O-glucoside, luteolin, and 3,5-dicaffeoylquinic acid), and yarrow's separator fraction (YSF), enriched in monoterpenes and sesquiterpenes, mainly containing camphor, artemisia ketone, and borneol. YE was effective in reducing reactive oxygen species (ROS) production in human gastric AGS cells by 16% to 29%, depending on the H. pylori strain. YPF had the highest inhibitory activity (38-40%) for ROS production. YE modulated the inflammatory response in AGS gastric cells, decreasing IL-8 production by 53% to 64%. This IL-8 inhibition also showed a strain-dependent character. YPF and YSF exhibited similar behavior, reducing IL-8 production, suggesting that both phenolic compounds and essential oils could contribute to IL-8 inhibition. YSF showed the highest antibacterial activity against H. pylori (6.3-7.1 log CFU reduction, depending on the strain) and lower MIC (0.08 mg/mL). Results obtained have shown that YE and SAF fractions (YPF and YSF) were effective as antioxidant, anti-inflammatory, and antibacterial agents regardless of the H. pylori strain characteristics.
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The aim of this work was to evaluate the influence of in vitro gastric digestion of two olive leaf extracts (E1 and E2) on their chemical composition and bioactive properties against Helicobacter pylori (H. pylori), one of the most successful and prevalent human pathogens. HPLC-PAD/MS analysis and anti-inflammatory, antioxidant, and antibacterial activities of both olive leaf extracts were carried out before and after their in vitro gastric digestion. The results showed that gastric digestion produced modifications of the chemical composition and bioactive properties of both olive leaf extracts. The main compounds in the extract E1 were hydroxytyrosol and its glucoside derivatives (14,556 mg/100 g), presenting all the identified compounds a more polar character than those found in the E2 extract. E2 showed a higher concentration of less polar compounds than E1 extract, with oleuropein (21,419 mg/100 g) being the major component. Gastric digestion during the fasted state (pH 2) induced an overall decrease of the most identified compounds. In the extract E1, while the anti-inflammatory capacity showed only a slight decrease (9% of IL-8 production), the antioxidant properties suffered a drastic drop (23% of ROS inhibition), as well as the antibacterial capacity. However, in the extract E2, these changes caused an increase in the anti-inflammatory (19% of IL-8 production) and antioxidant activity (9% of ROS inhibition), which could be due to the hydrolysis of oleuropein and ligustroside into their main degradation products, hydroxytyrosol and tyrosol, but the antibacterial activity was reduced. Gastric digestion during fed state (pH 5) had less influence on the composition of the extracts, affecting in a lesser degree their anti-inflammatory and antioxidant activity, although there was a decrease in the antibacterial activity in both extracts similar to that observed at pH 2.
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Helicobacter pylori (H. pylori) is one of the major human pathogens and the main cause of pathological damages that can progress from chronic gastritis to gastric cancer. During the colonization of gastric mucosa, this bacterium provokes a strong inflammatory response and subsequent oxidative process, which are associated with tissue damage. Therefore, the objective of this research was to evaluate the ability of two olive-leaf extracts (E1 and E2) to modulate the inflammatory response and oxidative stress in H. pylori-infected human gastric AGS cells. The obtained results showed that both extracts significantly decreased interleukin-8 (IL-8) secretion and reactive oxygen species (ROS) production in human gastric AGS cells. Both extracts also showed antibacterial activity against different H. pylori strains. HPLC-PAD-MS characterization demonstrated that extract E1 was mainly composed of highly hydrophilic compounds, such as hydroxytyrosol (HT) and its glucosides, and it was the most effective extract as an antibacterial agent. In contrast, extract E2 was composed mostly of moderately hydrophilic compounds, such as oleuropein (OLE), and it was more effective than extract E1 as an anti-inflammatory agent. Both extracts exhibited similar potential to decrease ROS production. These results show the importance of standardizing the extract composition according to the bioactive properties that should be potentiated.
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Helicobacter pylori (H. pylori) is a pathogenic bacteria identified as a potential risk factor for gastritis, gastric ulcers and gastric cancer. During the stomach colonization, H. pylori triggers a strong inflammatory response and subsequent oxidative stress, which are associated with tissue damage. For this reason, it is of particular interest to develop alternative natural tools that enable modulation of the associated damaging immune response. With this purpose, we obtained grape seed extract (GSE) from sweet (not fermented) food grade seeds. The aim of our study was to investigate the effect of GSE and its two enriched procyanidins fractions (OPC and PPC) on the inflammatory process and oxidative stress produced by different H. pylori strains in human gastric epithelial cells (AGS). Anti-inflammatory activity was evaluated by measuring the level of interleukin-8 (IL-8) secretion. IL-8 production was significantly reduced in H. pylori-infected human gastric epithelial cells pre-treated with GSE or its enriched fractions when compared with non-pre-treated infected cells (from 21.6% to 87.8%). Pre-treatment with GSE or its fractions significantly decreased intracellular reactive oxygen species (ROS) production in AGS cells after infection, depending on the H. pylori strain. Our results also showed that GSE and its fractions demonstrate antibacterial activity against all strains of H. pylori used in the study. This work demonstrates the effectiveness of GSE enriched in procyanidins against the main events associated with H. pylori infection.
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The management of Helicobacter pylori infection in children is a consistent problem in clinical practice. Over the years, many questions have been raised regarding symptoms associated with the infection, the diagnostic methods and type of treatment. What is most controversial is determining the criteria that enable us to initiate and carry out the study in children. In the last 10 years, pediatricians have followed the joint ESPGHAN/NASPGHAN guidelines published in 2011 and updated in 2017 in the management of H.pylori in children. This document aims to unify the study indication criteria as well as the diagnosis and treatment recommendations for H.pylori infection in children and adolescents, so they can be used in both Primary and Hospital care.
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The management of Helicobacter pylori infection in children is a consistent problem in clinical practice. Over the years, many questions have been raised regarding symptoms associated with the infection, the diagnostic methods and type of treatment. What is most controversial is determining the criteria that enable us to initiate and carry out the study in children. In the last 10 years, pediatricians have followed the joint ESPGHAN/NASPGHAN guidelines published in 2011 and updated in 2017 in the management of H. pylori in children. This document aims to unify the study indication criteria as well as the diagnosis and treatment recommendations for H. pylori infection in children and adolescents, so they can be used in both Primary and Hospital care.
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Infecciones por Helicobacter , Helicobacter pylori , Adolescente , Niño , Infecciones por Helicobacter/diagnóstico , HumanosRESUMEN
Strains of Helicobacter pylori (H. pylori) resistant to various antibiotics have increased in recent years. In this context, the search for new therapeutic approaches is crucial. The aim of the present study was to demonstrate the antibacterial activity of a procyanidin-rich extract obtained from food-grade winery grape seeds against 14 H. pylori strains and elucidate its phenolic composition. Ten strains (71.4%) showed resistance to at least some of the tested antibiotics, while four isolates (28.6%) were susceptible to all antibiotics. Resistance to more than one class of antibiotics was observed in six strains (42.9%). The extract was able to inhibit the growth of all H. pylori strains in a range of a minimum inhibitory concentration (MIC) from 0.015 mg/mL to 0.125 mg/mL, confirming also the existence of a strain-dependent effect. The phenolic composition determined by reverse phase high pressure liquid chromatography, photodiode array, and mass spectrometry detection (RP-HPLC-PAD-MS) analysis revealed the presence of 43 individual compounds and allowed the quantification of 41 of them, including seven procyanidin tetramers, seven procyanidin pentamers, and six galloylated procyanidin dimers, trimers, and tetramers. The extract was composed mainly by catechin and procyanidin oligomers with a total amount of 5.801 mg/100 g, which represent 92% of the total individual phenolic content. Among them, the most abundant were catechins (2.047 mg/100 g), followed by procyanidin dimers (1.550 mg/100 g), trimers (1.176 mg/100 g), tetramers (436 mg/100 g), and pentamers (296 mg/100 g) that represent 35, 27, 20, 8, and 5%, respectively of the total flavanol constituents. The composition profile information may help to improve the production process of useful antibacterial extracts against H. pylori.
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INTRODUCTION: The aim of this study was to know, through a national survey, the methods and techniques used for the diagnosis of Helicobacter pylori (Hp) in the different Clinical Microbiology Services/Laboratories in Spain, as well as antibiotic resistance data. METHODS: The survey requested information about the diagnostic methods performed for Hp detection in Clinical Microbiology laboratories, including serology, stool antigen, culture from gastric biopsies, and PCR. In addition, the performance of antibiotic susceptibility was collected. Data on the number of samples processed in 2016, positivity of each technique and resistance data were requested. The survey was sent by email (October-December 2017) to the heads of 198 Clinical Microbiology Laboratories in Spain. RESULTS: Overall, 51 centers from 29 regions answered the survey and 48/51 provided Hp microbiological diagnostic testing. Concerning the microbiological methods used to diagnose Hp infection, the culture of gastric biopsies was the most frequent (37/48), followed by stool antigen detection (35/48), serology (19/48) and biopsy PCR (5/48). Regarding antibiotic resistance, high resistance rates were observed, especially in metronidazole and clarithromycin (over 33%). CONCLUSION: Culture of gastric biopsies was the most frequent method for detection of Hp, but the immunochromatographic stool antigen test was the one with which the largest number of samples were analyzed. Nowadays, in Spain, it concerns the problem of increased antibiotic resistance to 'first-line' antibiotics.
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Técnicas de Laboratorio Clínico , Infecciones por Helicobacter , Helicobacter pylori , Farmacorresistencia Bacteriana , Infecciones por Helicobacter/diagnóstico , Humanos , EspañaRESUMEN
INTRODUCTION: In recent years an increase in the prevalence of colonization and infection by Scedosporium spp. in patients with cystic fibrosis (CF) has been observed. In this article, we study the frequency of isolation of Scedosporium spp. in an adult CF Unit, analyzing characteristics of the patients and predisposing factors. METHODS: A retrospective observational study was conducted in 87 adult CF patients in whom the presence of positive culture for Scedosporium spp. was tested for a 5-year period (January 2012-July 2017). We recorded the following clinical variables: age, sex, body mass index, genotype, presence of pancreatic insufficiency, bacterial colonization, lung function, other complications, exacerbations and treatment, and the modified Bhalla score from the last high-resolution computed tomography. Results were analyzed with IBM SPSS Statistics Version 22.0 software. RESULTS: Scedosporium spp. was isolated in 25.3% of patients. In the bivariate analysis, these patients showed a higher rate of Pseudomonas aeruginosa infection, worse score in the Bhalla classification (highlighting the following items: bronchiectasis, mucus plugs and bronchial generations), a slight decrease in the lung diffusion capacity and more frequently received inhaled antibiotics. In the logistic regression multivariate analysis, only the bronchial generations item was significant. CONCLUSION: Scedosporium spp. must be considered an emerging opportunistic pathogen in patients with CF whose clinical involvement, risk factors or need for treatment is unknown.
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Fibrosis Quística/microbiología , Scedosporium/aislamiento & purificación , Adulto , Antibacterianos/uso terapéutico , Antifúngicos/uso terapéutico , Estudios de Cohortes , Fibrosis Quística/fisiopatología , Femenino , Humanos , Modelos Logísticos , Masculino , Pseudomonas aeruginosa/aislamiento & purificación , Capacidad de Difusión Pulmonar , Estudios Retrospectivos , Esputo/microbiología , Adulto JovenRESUMEN
The human microbiota comprises all the microorganisms of our body, which can also be categorised as commensals, mutualists and pathogens according to their behaviour. Our knowledge of the human microbiota has considerably increased since the introduction of 16S rRNA next generation sequencing (16S rDNA gene). This technological breakthrough has seen a revolution in the knowledge of the microbiota composition and its implications in human health. This article details the different human bacterial ecosystems and the scientific evidence of their involvement in different diseases. The faecal microbiota transplant procedure, particularly used to treat recurrent diarrhoea caused by Clostridium difficile, and the methodological bases of the new molecular techniques used to characterise microbiota are also described.
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Trasplante de Microbiota Fecal , Microbioma Gastrointestinal , Trasplante de Microbiota Fecal/métodos , Microbioma Gastrointestinal/genética , Humanos , Análisis de Secuencia de ADNRESUMEN
El manejo de la infección por Helicobacter pylori en los niños es un dilema permanente en la práctica clínica. A lo largo de los años se han ido creando multitud de interrogantes respecto a los síntomas ligados a la infección, los métodos diagnósticos y los modos de tratamiento, siendo la más controvertida la indicación diagnóstica.En los últimos 10 años el colectivo pediátrico ha dispuesto de una guía elaborada por expertos de las Sociedades de Gastroenterología Pediátrica de Europa (ESPGHAN) y Estados Unidos (NASPGHAN) publicada en 2011 y actualizada en 2017 que nos ha orientado en el manejo de la infección por H.pylori en la edad pediátrica.El presente documento pretende unificar los criterios de indicación de estudio así como las pautas de diagnóstico y tratamiento de la infección por H.pylori en los niños y adolescentes para que puedan ser utilizadas tanto en atención primaria como en la clínica hospitalaria. (AU)
The management of Helicobacter pylori infection in children is a consistent problem in clinical practice. Over the years, many questions have been raised regarding symptoms associated with the infection, the diagnostic methods and type of treatment. What is most controversial is determining the criteria that enable us to initiate and carry out the study in children.In the last 10 years, pediatricians have followed the joint ESPGHAN/NASPGHAN guidelines published in 2011 and updated in 2017 in the management of H.pylori in children.This document aims to unify the study indication criteria as well as the diagnosis and treatment recommendations for H.pylori infection in children and adolescents, so they can be used in both Primary and Hospital care. (AU)
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Humanos , Recién Nacido , Lactante , Preescolar , Niño , Adolescente , Helicobacter pylori , Gastritis , España , GastroscopíaRESUMEN
La microbiota es el conjunto de microorganismos que reside en nuestro cuerpo, que a su vez pueden diferenciarse según su comportamiento en comensales, mutualistas y patógenos. El conocimiento de este ecosistema se ha visto considerablemente incrementado tras la introducción de las técnicas de secuenciación masiva del gen 16S ARNr (gen ADNr 16S). Este avance ha supuesto una verdadera revolución en el conocimiento de la composición de la microbiota y de su implicación en los estados de salud y enfermedad del ser humano. En este documento se detallan los diferentes ecosistemas bacterianos que podemos encontrar en el cuerpo humano y las evidencias científicas que existen en relación con diferentes enfermedades. También se describe el procedimiento de transferencia de materia fecal, particularmente utilizado para el tratamiento de las recidivas de la diarrea por Clostridium difficile, y las bases metodológicas de las nuevas técnicas moleculares utilizadas en la caracterización de la microbiota
The human microbiota comprises all the microorganisms of our body, which can also be categorised as commensals, mutualists and pathogens according to their behaviour. Our knowledge of the human microbiota has considerably increased since the introduction of 16S rRNA next generation sequencing (16S rDNA gene). This technological breakthrough has seen a revolution in the knowledge of the microbiota composition and its implications in human health. This article details the different human bacterial ecosystems and the scientific evidence of their involvement in different diseases. The faecal microbiota transplant procedure, particularly used to treat recurrent diarrhoea caused by Clostridium difficile, and the methodological bases of the new molecular techniques used to characterise microbiota are also described
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Humanos , Microbiota/fisiología , Trasplante de Microbiota Fecal/métodos , Metagenoma , Técnicas de Tipificación BacterianaRESUMEN
Las técnicas de diagnóstico rápido son herramientas de gran valor en el diagnóstico de las infecciones gastrointestinales, especialmente para la detección de algunos microorganismos y en determinados grupos de pacientes. Mientras que las técnicas de detección de antígeno son práctica habitual en los laboratorios de microbiología clínica para el diagnóstico de virus, algunos parásitos y algunas bacterias, las técnicas moleculares se utilizan de manera rutinaria solo para determinados patógenos (como Clostridium difficile). Sin embargo, son técnicas en constante evolución que permiten el diagnóstico rápido de un número cada vez mayor de patógenos con una elevada sensibilidad y especificidad y también permiten la detección de factores de virulencia o mecanismos de resistencia. Los sistemas de diagnóstico sindrómico, que detectan diferentes patógenos de forma simultánea, son muy prometedores porque permiten diagnosticar en pocas horas los patógenos más frecuentes y pueden ser de gran utilidad en determinados pacientes. Para el diagnóstico de la infección por Helicobacter pylori las técnicas moleculares, que pueden detectar tanto la bacteria como su resistencia a claritromicina y levofloxacino, permiten seleccionar el tratamiento más adecuado para cada paciente cuando el cultivo de la bacteria no es posible (AU)
Rapid diagnostic techniques are valuable tools in the diagnosis of gastrointestinal infections, especially for the detection of some microorganisms and in certain groups of patients. While antigen detection techniques are widely used in Clinical Microbiology laboratories, for the diagnosis of viruses, some parasites and some bacteria, molecular techniques are routinely used only for some pathogens (such as Clostridium difficile). However, molecular techniques are constantly evolving, and they allow a rapid diagnosis for an increasing number of pathogens, with high sensitivity and specificity. In addition, they are also able to detect virulence factors or resistance mechanisms. Syndromic surveillance systems, which detect different pathogens simultaneously, are very promising because they enable the most frequent pathogens to be diagnosed in a few hours and they can be very useful in certain patients. For the diagnosis of Helicobacter pylori infection, molecular techniques are able to detect bacteria and its resistance to clarithromycin and levofloxacin, allowing the most appropriate treatment to be selected for each patient when bacterial culture is not possible (AU)
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Humanos , Virosis/microbiología , Parasitosis Intestinales/microbiología , Enfermedades Intestinales/microbiología , Infecciones Bacterianas/microbiología , Técnicas Microbiológicas/métodos , Helicobacter pylori/aislamiento & purificación , Rotavirus/aislamiento & purificación , Clostridioides difficile/aislamiento & purificaciónAsunto(s)
Fibrosis Quística/complicaciones , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Infecciones por Mycobacterium no Tuberculosas/microbiología , Micobacterias no Tuberculosas , Antibacterianos/uso terapéutico , Humanos , Masculino , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Adulto JovenRESUMEN
No disponible
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Humanos , Masculino , Adulto , Mycobacterium , Mycobacterium/aislamiento & purificación , Infecciones por Mycobacterium/complicaciones , Infecciones por Mycobacterium/diagnóstico , Infecciones por Mycobacterium/tratamiento farmacológico , Fibrosis Quística/complicaciones , Fibrosis Quística/diagnóstico , Fibrosis Quística/tratamiento farmacológico , Infecciones por Mycobacterium no Tuberculosas/complicaciones , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Infecciones por Mycobacterium no Tuberculosas/epidemiologíaRESUMEN
BACKGROUND: Achromobacter xylosoxidans is an emerging pathogen in cystic fibrosis (CF). Although the rate of colonization by this microorganism is variable, prevalence is increasing in CF units. METHODS: A microbiological/clinical study was conducted on of adult CF patients harboring A. xylosoxidans. Identification and susceptibility testing were performed using MicroScan (Siemens). Decline in lung function was assessed using the variable, annual percentage loss of FEV1 (forced expiratory volume in 1 s). RESULTS: A. xylosoxidans was isolated in 18 (19.8%) of 91 patients over a 14-year period. Mean age was 26.6 years (18-39 years). Nine patients (9.8%) were chronically colonized. Piperacillin/tazobactam and imipenem were the most active antibiotics. Mean annual decline in lung function in chronically colonized patients was 2.49%. CONCLUSIONS: A. xylosoxidans is a major pathogen in CF. A decreased lung function was observed among patients who were chronically colonized by A. xylosoxidans. Antibiotic therapy should be started early in order to prevent chronic colonization by this microorganism
INTRODUCCIÓN: Achromobacter xylosoxidans es un patógeno emergente en fibrosis quística (FQ). Aunque la tasa de colonización por este microorganismo es variable, la prevalencia está aumentando en las unidades de FQ. MÉTODOS: Llevamos a cabo un estudio clínico-microbiológico de los pacientes adultos con FQ portadores de A. xylosoxidans. La identificación y sensibilidad fueron realizadas usando MicroScan (Siemens). La pérdida de función pulmonar fue evaluada por la variable porcentaje anual de pérdida de FEV1. RESULTADOS: A. xylosoxidans fue aislado en 18 (19.8%) de 91 pacientes, en un periodo de 14 años. La edad media fue 26.6 años (18-39 años). Nueve pacientes (9.8%) presentaban colonización crónica. Piperacilina/tazobactam e imipenem fueron los antibióticos más activos. La media anual de pérdida de función pulmonar en los pacientes colonizados de forma crónica fue 2.6%. CONCLUSIONES: A. xylosoxidans es un importante patógeno en FQ. Observamos pérdida de la función pulmonar en los pacientes colonizados de forma crónica por A. xylosoxidans. El tratamiento antibiótico debe iniciarse lo más rápido posible para prevenir la colonización crónica por este microorganismo