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Introduction: Acinetobacter baumannii contributes significantly to the global issue of multidrug-resistant (MDR) nosocomial infections. Often, these strains demonstrate resistance to carbapenems (MDR-CRAB), the first-line treatment for infections instigated by MDR A. baumannii. Our study focused on the antimicrobial susceptibility and genomic sequences related to plasmids from 12 clinical isolates of A. baumannii that carry both the blaOXA-58 and bla NDM-1 carbapenemase genes. Methods: Whole-genome sequencing with long-read technology was employed for the characterization of an A. baumannii plasmid that harbors the bla OXA-58 and blaNDM-1 genes. The location of the bla OXA-58 and bla NDM-1 genes was confirmed through Southern blot hybridization assays. Antimicrobial susceptibility tests were conducted, and molecular characterization was performed using PCR and PFGE. Results: Multilocus Sequence Typing analysis revealed considerable genetic diversity among bla OXA-58 and bla NDM-1 positive strains in Brazil. It was confirmed that these genes were located on a plasmid larger than 300 kb in isolates from the same hospital, which also carry other antimicrobial resistance genes. Different genetic contexts were observed for the co-occurrence of these carbapenemase-encoding genes in Brazilian strains. Discussion: The propagation of bla OXA-58 and bla NDM-1 genes on the same plasmid, which also carries other resistance determinants, could potentially lead to the emergence of bacterial strains resistant to multiple classes of antimicrobials. Therefore, the characterization of these strains is of paramount importance for monitoring resistance evolution, curbing their rapid global dissemination, averting outbreaks, and optimizing therapy.
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Due to recent developments in NGS technologies, genome sequencing is generating large volumes of new data containing a wealth of biological information. Understanding sequenced genomes in a biologically meaningful way and delineating their functional and metabolic landscapes is a first-level challenge. Considering the global antimicrobial resistance (AMR) problem, investments to expand surveillance and improve existing genome analysis technologies are pressing. In addition, the speed at which new genomic data is generated surpasses our capacity to analyze it with available bioinformatics methods, thus creating a need to develop new, user-friendly and comprehensive analytical tools. To this end, we propose a new web application, CABGen, developed with open-source software. CABGen allows storing, organizing, analyzing, and interpreting bioinformatics data in a friendly, scalable, easy-to-use environment and can process data from bacterial isolates of different species and origins. CABGen has three modules: Upload Sequences, Analyze Sequences, and Verify Results. Functionalities include coverage estimation, species identification, de novo genome assembly, and assembly quality, genome annotation, MLST mapping, searches for genes related to AMR, virulence, and plasmids, and detection of point mutations in specific AMR genes. Visualization tools are also available, greatly facilitating the handling of biological data. The reports include those results that are clinically relevant. To illustrate the use of CABGen, whole-genome shotgun data from 181 bacterial isolates of different species collected in 5 Brazilian regions between 2018 and 2020 were uploaded and submitted to the platform's modules.
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The high rates of carbapenem resistance among Brazilian Pseudomonas aeruginosa isolates are mainly associated with the clone ST277 producing the carbapenemase SPM-1. Here, the complete genetic composition of a IncP plasmid harboring blaKPC-2 in isolates of this endemic clone carrying chromosomal blaSPM-1 was described using whole genome sequencing. These results confirm the association of these two carbapenemases in ST277 and also describe the genetic composition of a novel blaKPC-2-plasmid. Considering the fact that this association occurs in a high-risk clone, monitoring the dissemination of this plasmid should be a public health concern.
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Infecções por Pseudomonas , Pseudomonas aeruginosa , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Brasil/epidemiologia , Humanos , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa/genética , beta-Lactamases/genéticaRESUMO
Burkholderia cepacia complex (Bcc) comprises 24 related species genetically distinct, associated with high mortality in cystic fibrosis (CF) patients. Due to a high level of similarity among Bcc species, accurate identification has been problematic, and most conventional and automated phenotypic tests have shown low accuracy. We evaluated accuracy of MALDI-ToF MS decreasing the cut-off score value to distinguish Bcc species compared to recA gene sequencing. A total of 145 Bcc isolates were analyzed. B. vietnamiensis (41.37%), B. cenocepacia IIIA (23.44%), B. multivorans (20%), B. cenocepacia IIIB (11.03%), and B. contaminans (2.75%) among other species were identified by recA sequencing. MALDI-ToF MS identified 100% of Bcc isolates at the genus level and 53.1% at the species level. By decreasing cut-off values for ≥1.70, the correct identification at the species level increased to 74.5%. MALDI-ToF MS proved to be useful at the genus level identification, but it still requires improvements that allow more precise identification, requiring continuous updates and addition of new spectra to its database. A review of interpretative criteria is a field to be explored with a large collection of Bcc species.
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Infecções por Burkholderia , Complexo Burkholderia cepacia , Fibrose Cística , Técnicas de Tipagem Bacteriana , Complexo Burkholderia cepacia/genética , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Multidrug-resistant microorganisms are a well-known global problem, and gram-negative bacilli are top-ranking. When these pathogens are associated with bloodstream infections (BSI), outcomes become even worse. Here we applied whole-genome sequencing to access information about clonal distribution, resistance mechanism diversity and other molecular aspects of gram-negative bacilli (GNB) isolated from bloodstream infections in Brazil. It was possible to highlight international high-risk clones circulating in the Brazilian territory, such as CC258 for Klebsiella pneumoniae, ST79 for Acinetobacter baumannii and ST233 for Pseudomonas aeruginosa. Important associations can be made such as a negative correlation between CRISPR-Cas and K. pneumoniae CC258, while the genes bla TEM, bla KPC and bla CTX-M are highly associated with this clone. Specific relationships between A. baumannii clones and bla OXA-51 variants were also observed. All P. aeruginosa ST233 isolates showed the genes bla VIM and bla OXA486. In addition, some trends could be identified, where a new P. aeruginosa MDR clone (ST3079), a novel A. baumannii clonal profile circulating in Brazil (ST848), and important resistance associations in the form of bla VIM-2 and bla IMP-56 being found together in one ST233 strain, stand out. Such findings may help to develop approaches to deal with BSI and even other nosocomial infections caused by these important GNB.
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The application of next-generation sequencing tools revealed that the cystic fibrosis respiratory tract is a polymicrobial environment. We have characterized the airway bacterial microbiota of five adult patients with cystic fibrosis during a 14-month period by 16S rRNA tag sequencing using the Illumina technology. Microbial diversity, estimated by the Shannon index, varied among patient samples collected throughout the follow-up period. The beta diversity analysis revealed that the composition of the airway microbiota was highly specific for each patient, showing little variation among the samples of each patient analyzed over time. The composition of the bacterial microbiota did not reveal any emerging pathogen predictor of pulmonary disease in cystic fibrosis or of its unfavorable clinical progress, except for unveiling the presence of anaerobic microorganisms, even without any established clinical association. Our results could potentialy help us to translate and develop strategies in response to the pathobiology of this disease, particularly because it represents an innovative approach for CF centers in Brazil.
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Fibrose Cística/microbiologia , Microbiota , Sistema Respiratório/microbiologia , Adulto , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Brasil , DNA Bacteriano/genética , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Adulto JovemRESUMO
Stenotrophomonas maltophilia is one of the Gram-negative bacilli most frequently found in the airways of cystic fibrosis patients. This opportunistic pathogen is intrinsically multidrug-resistant, and therefore, its treatment presents a challenge. The genetic characterization of S. maltophilia is largely unknown, especially from those strains that colonize/infect the airways of cystic fibrosis patients. This work reports the draft genome sequences of three S. maltophilia isolates recovered from the sputum of a cystic fibrosis pediatric patient in Southeast Brazil. Several resistance- and virulence-related genes were detected. Furthermore, one intact phage and one incomplete prophage region were also identified in all strains. Multilocus sequence typing showed that all strains belonged to a new sequence type (ST264). Interestingly, all S. maltophilia strains were genetically identical, showing persistence for at least 16 months. To our knowledge, this is the first report of S. maltophilia draft genome sequences obtained from a cystic fibrosis pediatric patient in Brazil.
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Fibrose Cística/microbiologia , Genoma Bacteriano , Infecções por Bactérias Gram-Negativas/microbiologia , Stenotrophomonas maltophilia/genética , Antibacterianos/farmacologia , Sequência de Bases , Brasil , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Stenotrophomonas maltophilia/efeitos dos fármacos , Stenotrophomonas maltophilia/isolamento & purificaçãoRESUMO
OBJECTIVE: High-resolution computed tomography (HRCT) allows the early detection of pathological changes in the lung structure, and reproducible scoring systems can be used to quantify chest computed tomography (CT) findings in patients with cystic fibrosis (CF). The aim of the study was to describe early HRCT findings according to a validated scoring system in infants with CF diagnosed by newborn screening (NBS). METHODS: This cross-sectional study included infants with CF diagnosed by NBS who were born between January 2013 and January 2017 and who underwent HRCT scanning within the first year after diagnosis when they were clinically stable. The CT scans were evaluated using the modified Bhalla score. RESULTS: Thirty-two subjects underwent HRCT scanning. The mean total-modified Bhalla score was 3.6±2.1, and 93.8% of the scans were abnormal. Pseudomonas aeruginosa airway colonization was associated with increased modified Bhalla score values. Bronchial wall thickening was the most common feature (90.6%), followed by bronchial collapse/consolidation (59.4%), mosaic attenuation/perfusion (50%), bronchiectasis (37.5%) and mucus plugging (15.6%). Bronchial wall thickening was diffuse in most of the patients. CONCLUSION: A substantial proportion of infants diagnosed with CF after detection by NBS already showed evidence of lung disease. P. aeruginosa colonization was associated with increased Bhalla scores, highlighting the importance of this CF pathogen in early structural lung disease. The presence of bronchial wall thickening at such a young age may reflect the presence of airway inflammatory processes. The detection and quantification of structural abnormalities with the modified Bhalla score may aid in the identification of lung disease before it is clinically apparent.
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Fibrose Cística/diagnóstico por imagem , Triagem Neonatal , Bronquiectasia/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Tomografia Computadorizada por Raios X/métodosRESUMO
We present a post-operative infection caused by a methicillin-resistant Staphylococcus aureus strain, previously isolated in the preoperative screening, in a patient submitted to femoral osteosynthesis, successfully treated with oral ciprofloxacin. The isolate exhibited in vitro resistance to ciprofloxacin, Staphylococcal Cassette Chromosome mec type IV, it was negative for the lukS-PV Panton-Valentine leucocidin gene and belonged to ST2594 in multilocus sequence typing analysis. Whole genome sequencing revealed a genome size of 2,818,289 base pairs. The annotated genomes of ST2594 and N315 strains were compared, looking for genes related to virulence and resistance. The lack of the tst, sec, sel genes, associated with a mutation in the clfA gene, may partially explain the low morbity in this case.
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Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Complicações Pós-Operatórias/microbiologia , Infecções Estafilocócicas/microbiologia , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Ciprofloxacina/farmacologia , Farmacorresistência Bacteriana , Feminino , Genoma Bacteriano , Virilha/microbiologia , Humanos , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Complicações Pós-Operatórias/tratamento farmacológico , Período Pré-Operatório , Infecções Estafilocócicas/tratamento farmacológico , Fatores de Virulência/genética , Sequenciamento Completo do GenomaRESUMO
OBJECTIVE: High-resolution computed tomography (HRCT) allows the early detection of pathological changes in the lung structure, and reproducible scoring systems can be used to quantify chest computed tomography (CT) findings in patients with cystic fibrosis (CF). The aim of the study was to describe early HRCT findings according to a validated scoring system in infants with CF diagnosed by newborn screening (NBS). METHODS: This cross-sectional study included infants with CF diagnosed by NBS who were born between January 2013 and January 2017 and who underwent HRCT scanning within the first year after diagnosis when they were clinically stable. The CT scans were evaluated using the modified Bhalla score. RESULTS: Thirty-two subjects underwent HRCT scanning. The mean total-modified Bhalla score was 3.6±2.1, and 93.8% of the scans were abnormal. Pseudomonas aeruginosa airway colonization was associated with increased modified Bhalla score values. Bronchial wall thickening was the most common feature (90.6%), followed by bronchial collapse/consolidation (59.4%), mosaic attenuation/perfusion (50%), bronchiectasis (37.5%) and mucus plugging (15.6%). Bronchial wall thickening was diffuse in most of the patients. CONCLUSION: A substantial proportion of infants diagnosed with CF after detection by NBS already showed evidence of lung disease. P. aeruginosa colonization was associated with increased Bhalla scores, highlighting the importance of this CF pathogen in early structural lung disease. The presence of bronchial wall thickening at such a young age may reflect the presence of airway inflammatory processes. The detection and quantification of structural abnormalities with the modified Bhalla score may aid in the identification of lung disease before it is clinically apparent.
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Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Triagem Neonatal , Fibrose Cística/diagnóstico por imagem , Bronquiectasia/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Estudos TransversaisRESUMO
Abstract Identification of nonfermenting Gram-negative bacteria (NFGNB) of cystic fibrosis patients is hard and misidentification could affect clinical outcome. This study aimed to propose a scheme using polymerase chain reaction to identify NFGNB. This scheme leads to reliable identification within 3 days in an economically viable manner when compared to other methods.
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Humanos , Reação em Cadeia da Polimerase/métodos , Infecções por Bactérias Gram-Negativas/diagnóstico , Fibrose Cística/complicações , Técnicas de Diagnóstico Molecular/métodos , Bactérias Gram-Negativas/isolamento & purificação , Fatores de Tempo , Bactérias Gram-Negativas/genéticaRESUMO
Identification of nonfermenting Gram-negative bacteria (NFGNB) of cystic fibrosis patients is hard and misidentification could affect clinical outcome. This study aimed to propose a scheme using polymerase chain reaction to identify NFGNB. This scheme leads to reliable identification within 3 days in an economically viable manner when compared to other methods.
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Fibrose Cística/complicações , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase/métodos , Bactérias Gram-Negativas/genética , Humanos , Fatores de TempoRESUMO
ABSTRACT CONTEXT AND OBJECTIVE: The prevalence of a variety of potentially pathogenic microorganisms in cystic fibrosis patients, such as methicillin-resistant Staphylococcus aureus (MRSA), has increased over the past decade. Given the increasing prevalence of MRSA and the few data available in the literature, better understanding of the clinical repercussions of colonization by this bacterium in cystic fibrosis patients becomes essential. This study aimed to evaluate the repercussions of chronic colonization by MRSA in cystic fibrosis patients. DESIGN AND SETTING: Retrospective cohort study from January 2004 to December 2013 in a cystic fibrosis reference center. METHODS: Each patient with cystic fibrosis was evaluated for nutritional status (body mass index, BMI, and BMI percentile), pulmonary function and tomographic abnormalities (modified Bhalla scores) at the time of chronic colonization by MRSA or methicillin-susceptible Staphylococcus aureus (MSSA) and throughout the study period. RESULTS: Twenty pairs of patients were included. There were no significant differences between the groups regarding nutritional characteristics. Spirometric data showed a trend towards greater obstruction of the airways in patients with MRSA. Patients with MRSA presented greater structural damage to their lungs, demonstrated not only by the total Bhalla score but also by its parameters individually. CONCLUSIONS: Patients colonized by MRSA presented greater functional and structural respiratory impairment at the time of chronic colonization. Disease progression was also faster in patients chronically colonized by MRSA than in those with MSSA. This was shown through comparisons that avoided possible confounding variables.
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Humanos , Masculino , Feminino , Pré-Escolar , Criança , Infecções Estafilocócicas/microbiologia , Fibrose Cística/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Doença Crônica , Estudos Retrospectivos , Estudos de CoortesRESUMO
CONTEXT AND OBJECTIVE: The prevalence of a variety of potentially pathogenic microorganisms in cystic fibrosis patients, such as methicillin-resistant Staphylococcus aureus (MRSA), has increased over the past decade. Given the increasing prevalence of MRSA and the few data available in the literature, better understanding of the clinical repercussions of colonization by this bacterium in cystic fibrosis patients becomes essential. This study aimed to evaluate the repercussions of chronic colonization by MRSA in cystic fibrosis patients. DESIGN AND SETTING: Retrospective cohort study from January 2004 to December 2013 in a cystic fibrosis reference center. METHODS: Each patient with cystic fibrosis was evaluated for nutritional status (body mass index, BMI, and BMI percentile), pulmonary function and tomographic abnormalities (modified Bhalla scores) at the time of chronic colonization by MRSA or methicillin-susceptible Staphylococcus aureus (MSSA) and throughout the study period. RESULTS: Twenty pairs of patients were included. There were no significant differences between the groups regarding nutritional characteristics. Spirometric data showed a trend towards greater obstruction of the airways in patients with MRSA. Patients with MRSA presented greater structural damage to their lungs, demonstrated not only by the total Bhalla score but also by its parameters individually. CONCLUSIONS: Patients colonized by MRSA presented greater functional and structural respiratory impairment at the time of chronic colonization. Disease progression was also faster in patients chronically colonized by MRSA than in those with MSSA. This was shown through comparisons that avoided possible confounding variables.
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Fibrose Cística/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/microbiologia , Criança , Pré-Escolar , Doença Crônica , Estudos de Coortes , Feminino , Humanos , Masculino , Estudos RetrospectivosRESUMO
BACKGROUND: Burkholderia cepacia complex is a group of opportunistic pathogens in cystic fibrosis (CF) patients believed to be associated with poor prognosis and patient-to-patient transmissibility. Little is known about clinical outcomes after B. vietnamiensis chronic colonization/infection. CASE PRESENTATION: A 33 yo male patient had diagnosis of CF by 7 yo, after recurrent pneumonia during infancy and lobectomy (left upper lobe) at 6 yo. Burkholderia cepacia complex (Bcc) was first isolated by 13 yo, and the patient fulfilled the criteria for chronic colonization by 15 yo. In the following 16 years (1997-2013), there was intermittent isolation of P. aeruginosa and continuous isolation of Bcc, identified as B. vietnamiensis. There was clinical and laboratorial stability for 16 years with annual rate of decline in forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) of 1.61 and 1.35%, respectively. From 2013 to 2015, there was significant clinical and lung function deterioration: annual rate of decline in FEV1 and FVC was 3 and 4.1%, respectively while body mass index decreased from 18.1 to 17.1. Episodes of hemoptysis and respiratory exacerbations (with hospital admissions) became more frequent. CF related diabetes was diagnosed (fasting glycemia: 116 mg/dL, oral glucose tolerance test: 305 mg/dL). Because of the severity of the disease in the last years, in addition to traditional microbiological surveillance, microbiome analysis by next generation sequencing (NGS) was performed on respiratory secretions. The NGS showed that 97% of the sequencing data were attributed to genus Burkholderia. CONCLUSIONS: We report the case of a 33-year-old male CF patient known to have chronic infection with B. vietnamiensis who remained clinically stable for 16 years and presented recent clinical and laboratorial deterioration. Microbiome analysis of respiratory secretions was performed in 3 samples collected in 2014-2015. Clinical deterioration overlapped with cystic fibrosis-related diabetes and microbiome composition revealed no significant differences when compared microbiome results to culture dependent methods.
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Complexo Burkholderia cepacia/isolamento & purificação , Portador Sadio/microbiologia , Fibrose Cística/microbiologia , Fibrose Cística/fisiopatologia , Sistema Respiratório/microbiologia , Adolescente , Adulto , Brasil , Criança , Fibrose Cística/complicações , Diabetes Mellitus/etiologia , Progressão da Doença , Volume Expiratório Forçado , Humanos , Masculino , Microbiota , Pseudomonas aeruginosa/isolamento & purificação , Capacidade Vital , Adulto JovemRESUMO
Abstract The distinction between healthcare-associated MRSA (HA-MRSA) and community-associated MRSA (CA-MRSA) infections has become increasingly blurred. We assessed the molecular characterization and antimicrobial resistance profile for MRSA isolates from blood. Most of all (81.9%) isolates are related to known HA-MRSA and CA-MRSA epidemic lineages, such as, USA300, USA400, USA600, USA800 and USA1100. This is the first multicenter study in Rio de Janeiro.
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Infecções Estafilocócicas/microbiologia , Bacteriemia/microbiologia , Farmacorresistência Bacteriana , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Tipagem de Sequências Multilocus , Antibacterianos/farmacologia , Brasil , Testes de Sensibilidade Microbiana , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , GenótipoRESUMO
INTRODUCTION: The clinical relevance of Achromobacter xylosoxidans infection in cystic fibrosis (CF) remains controversial. This emerging agent in CF has been associated with increased lung inflammation, more frequent exacerbations and more severe lung disease. We describe a pair of CF siblings chronically colonized by the same multilocus genotype of A. xylosoxidans with different clinical courses, and assess whether this species may have developed any virulence traits and antimicrobial resistance that could have contributed to their singular outcomes. CASE PRESENTATION: Two siblings were positive for the F508del and Y1092X mutations, and were chronically colonized by Pseudomonas aeruginosa and Staphylococcus aureus. The female patient had a more severe CF phenotype and faster clinical deterioration than her brother. Her pulmonary function and computed tomography scan lesions were worse than those of her brother, and both parameters progressively declined. She died at 14 years of age, when he was 18. All isolates of A. xylosoxidans were biofilm producers. Achromobacter xylosoxidans showed less swarming motility in the female patient. CONCLUSIONS: Biofilm production and diminution of motility allow persistence. Only swarming motility differed between the isolates recovered from the two siblings, but this finding is not sufficient to explain the different clinical outcomes despite their similar genotypes. Modifier genes, unknown environmental factors and female gender can partially explain differences between these siblings. We were unable to correlate any microbiological findings with their clinical courses, and more translational studies are necessary to decrease the gap of knowledge between laboratory and clinical data to promote better clinical interventions.
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The distinction between healthcare-associated MRSA (HA-MRSA) and community-associated MRSA (CA-MRSA) infections has become increasingly blurred. We assessed the molecular characterization and antimicrobial resistance profile for MRSA isolates from blood. Most of all (81.9%) isolates are related to known HA-MRSA and CA-MRSA epidemic lineages, such as, USA300, USA400, USA600, USA800 and USA1100. This is the first multicenter study in Rio de Janeiro.
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Antibacterianos/farmacologia , Bacteriemia/microbiologia , Farmacorresistência Bacteriana , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Tipagem de Sequências Multilocus , Infecções Estafilocócicas/microbiologia , Brasil , Genótipo , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade MicrobianaRESUMO
Broth microdilution, agar dilution, Etest® and disk diffusion techniques were compared to evaluate the susceptibility profile of 82 Bcc clinical isolates against six antimicrobials as recommended by CLSI. Broth microdilution was considered the "gold standard" method. The regression analysis was applied to determine the essential (EA) and categorical (CA) agreement rates. STX (MIC50, 1 mg/L) was the most potent antimicrobial tested against Bcc isolates. The worst in vitro activity was observed for chloramphenicol (MIC50, 16 mg/L) and ticarcillin-clavulanic acid (MIC50, >256 mg/L). The EA among broth microdilution and agar dilution results was good for the majority of antimicrobial tested. When comparing broth microdilution and Etest®, ceftazidime, SXT and chloramphenicol exhibited EA rates below 90%. SXT showed an excellent CA (100%) when dilution methodologies were compared. However, a low CA rate was found for this agent between dilution and disk diffusion methodologies resulting in unacceptable very major and minor error rates.
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Antibacterianos/farmacologia , Complexo Burkholderia cepacia/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Infecções por Burkholderia/microbiologia , HumanosRESUMO
BACKGROUND: Pulmonary deterioration after B.cepacia complex (BCC) colonization has a heterogeneous pattern. The aim was to investigate the clinical outcome of BCC colonization in CF patients chronically colonized with P. aeruginosa. METHODS: CF patients chronically colonized with P. aeruginosa were divided into three groups: intermittent (I), chronic (II) and no colonization (III) with BCC. Body mass index (BMI) percentile and spirometric parameters were analyzed at three different times in each group. RESULTS: Fifty-six patients chronically colonized with P. aeruginosa were included. Of these, 27 also had evidence of BCC colonization (13 intermittent and 14 chronic). BMI percentile was significantly lower among patients chronically colonized by both P. aeruginosa and BCC. Mean values of FEV1 and FVC % were also significantly lower in these patients, both at the time of chronic BCC colonization and 24 months forward. CONCLUSIONS: Chronic BCC colonization is associated with significant loss of lung function. Lower BMI might be a risk factor for chronic BCC colonization, preceding these events.