RESUMO
Persistent methicillin-resistant Staphylococcus aureus (MRSA) infection in cystic fibrosis (CF) patients has been associated with a more rapid decline in lung function, increased hospitalisation and mortality. The aim of this study was to evaluate the clonal relationships among 116 MRSA isolates from 12 chronically colonised CF pediatric patients over a 6-year period in a Rio de Janeiro CF specialist centre. Isolates were characterised by antimicrobial resistance, SCCmec type, presence of Panton-Valentine Leukocidin (PVL) genes and grouped according to DNA macrorestriction profile by pulsed-field gel electrophoresis (PFGE) and spa gene type. High resistance rates were detected for erythromycin (78%) and ciprofloxacin (50%) and SCCmec IV was the most common type (72.4%). Only 8.6% of isolates were PVL positive. High genetic diversity was evident by PFGE (39 pulsotypes) and of nine that were identified spa types, t002 (53.1%) and t539 (14.8%) were the most prevalent. We conclude that the observed homogeneity of spa types within patients over the study period demonstrates the persistence of such strain lineages throughout the course of chronic lung infection.
Assuntos
Fibrose Cística/microbiologia , Staphylococcus aureus Resistente à Meticilina/genética , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Brasil/epidemiologia , Portador Sadio , Criança , Humanos , Resistência a MeticilinaRESUMO
We describe the first detection of a KPC-2- and QnrB-producing Enterobacter cloacae from a patient with cystic fibrosis. The blaKPC-2 and qnrB-1 genes were located in a 79.8-kb plasmid. The presence of blaKPC-2 and qnrB-1 genes was determined by PCR and sequencing. Mobilization of plasmid containing blaKPC2 gene was assayed by conjugation.
RESUMO
Acinetobacter spp. are important healthcare pathogens, being closely linked to antibiotic resistance and outbreaks worldwide. Although such species are rarely observed in patients with cystic fibrosis (CF), we describe the characteristics of 53 strains of Acinetobacter spp. isolated from the sputum of 39 Brazilian patients with CF. The species distribution was A. baumannii (n = 29), A. pittii (n = 13), A. nosocomialis (n = 8), A. seifertii (n = 1), A. soli (n = 1) and A. variabilis (n = 1) determined by partial rpoB gene sequencing. Sixteen strains (10 A. baumannii, 3 A. pittii and 3 A. nosocomialis) were multidrug-resistant (MDR) by disk diffusion test (30%) and eight MDR carbapenem-resistant A. baumannii strains harboured the bla OXA-23-like oxacillinase gene. Thirty-three sequence types (STs) were identified by multilocus sequence typing of which eight were novel (A. baumannii: 843, 844, 845, 847, 848; A. pitti: 643; A. nosocomialis: 862 and A. seifertii: 846); six STs (2 A. baumannii, 3 A. pittii and 1 A. nosocomialis) were found in more than one patient. Four strains of A. baumannii were assigned to two common clonal complexes (CCs), namely, CC1 (ST1, ST20 and ST160), and CC79 (ST79). This study underlines the extensive species diversity of Acinetobacter spp. strains in CF lung infections which may present difficulties for therapy due to significant antimicrobial resistance.
Assuntos
Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/microbiologia , Antibacterianos/farmacologia , Fibrose Cística/microbiologia , Farmacorresistência Bacteriana , Infecções por Acinetobacter/epidemiologia , Adulto , Algoritmos , Brasil/epidemiologia , Criança , Humanos , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Escarro/microbiologiaRESUMO
Achromobacter spp. are opportunistic pathogens increasingly recovered from adult patients with cystic fibrosis (CF). We report the characterization of 122 Achromobacter spp. isolates recovered from 39 CF patients by multilocus sequence typing, virulence traits, and susceptibility to antimicrobials. Two species, A. xylosoxidans (77%) and A. ruhlandii (23%) were identified. All isolates showed a similar biofilm formation ability, and a positive swimming phenotype. By contrast, 4·3% and 44·4% of A. xylosoxidans and A. ruhlandii, respectively, exhibited a negative swarming phenotype, making the swimming and swarming abilities of A. xylosoxidans significantly higher than those of A. ruhlandii. A. xylosoxidans isolates from an outbreak clone also exhibited significantly higher motility. Both species were generally susceptible to ceftazidime, ciprofloxacin, imipenem and trimethoprim/sulphamethoxazole and there was no significant difference in susceptibility between isolates from chronic or sporadic infection. However, A. xylosoxidans isolates from chronic and sporadic cases were significantly more resistant to imipenem and ceftazidime than isolates of the outbreak clone.
Assuntos
Achromobacter/isolamento & purificação , Fibrose Cística/complicações , Infecções por Bactérias Gram-Negativas/microbiologia , Fatores de Virulência/análise , Achromobacter/classificação , Achromobacter/efeitos dos fármacos , Achromobacter/fisiologia , Antibacterianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Humanos , Locomoção , Testes de Sensibilidade Microbiana , Tipagem de Sequências MultilocusRESUMO
The rate of diagnosis of colonization/infection of the airways with Achromobacter xylosoxidans has increased in cystic fibrosis patients, but its clinical significance is still controversial. This retrospective, case-control study aimed to evaluate the clinical impact of A. xylosoxidans colonization/infection in cystic fibrosis patients. Individuals who were chronically colonized/infected (n=10), intermittently colonized/infected (n=15), and never colonized/infected with A. xylosoxidans (n=18) were retrospectively evaluated during two periods that were 2 years apart. Demographic characteristics, clinical data, lung function, and chronic bacterial co-colonization data were evaluated. Of the total study population, 87% were pediatric patients and 65.1% were female. Individuals chronically colonized/infected with A. xylosoxidans had decreased forced expiratory volume in 1 s (51.7% in the chronic colonization/infection group vs 82.7% in the intermittent colonization/infection group vs 76% in the never colonized/infected group). Compared with the other two groups, the rate of co-colonization with methicillin-resistant Staphylococcus aureus was higher in individuals chronically colonized/infected with A. xylosoxidans (P=0.002). Changes in lung function over 2 years in the three groups were not significant, although a trend toward a greater decrease in lung function was observed in the chronically colonized/infected group. Compared with the other two groups, there was a greater number of annual hospitalizations in patients chronically colonized/infected with A. xylosoxidans (P=0.033). In cystic fibrosis patients, there was an increased frequency of A. xylosoxidans colonization/infection in children, and lung function was reduced in patients who were chronically colonized/infected with A. xylosoxidans. Additionally, there were no differences in clinical outcomes during the 2-year period, except for an increased number of hospitalizations in patients with A. xylosoxidans.
Assuntos
Achromobacter denitrificans/isolamento & purificação , Fibrose Cística/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Adolescente , Adulto , Fatores Etários , Análise de Variância , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Volume Expiratório Forçado , Humanos , Lactente , Pulmão/fisiopatologia , Masculino , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Valores de Referência , Estudos Retrospectivos , Estatísticas não Paramétricas , Fatores de Tempo , Adulto JovemRESUMO
The rate of diagnosis of colonization/infection of the airways with Achromobacter xylosoxidans has increased in cystic fibrosis patients, but its clinical significance is still controversial. This retrospective, case-control study aimed to evaluate the clinical impact of A. xylosoxidans colonization/infection in cystic fibrosis patients. Individuals who were chronically colonized/infected (n=10), intermittently colonized/infected (n=15), and never colonized/infected with A. xylosoxidans (n=18) were retrospectively evaluated during two periods that were 2 years apart. Demographic characteristics, clinical data, lung function, and chronic bacterial co-colonization data were evaluated. Of the total study population, 87% were pediatric patients and 65.1% were female. Individuals chronically colonized/infected with A. xylosoxidans had decreased forced expiratory volume in 1 s (51.7% in the chronic colonization/infection group vs 82.7% in the intermittent colonization/infection group vs 76% in the never colonized/infected group). Compared with the other two groups, the rate of co-colonization with methicillin-resistant Staphylococcus aureus was higher in individuals chronically colonized/infected with A. xylosoxidans (P=0.002). Changes in lung function over 2 years in the three groups were not significant, although a trend toward a greater decrease in lung function was observed in the chronically colonized/infected group. Compared with the other two groups, there was a greater number of annual hospitalizations in patients chronically colonized/infected with A. xylosoxidans (P=0.033). In cystic fibrosis patients, there was an increased frequency of A. xylosoxidans colonization/infection in children, and lung function was reduced in patients who were chronically colonized/infected with A. xylosoxidans. Additionally, there were no differences in clinical outcomes during the 2-year period, except for an increased number of hospitalizations in patients with A. xylosoxidans.
Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Adulto Jovem , Achromobacter denitrificans/isolamento & purificação , Fibrose Cística/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Fatores Etários , Análise de Variância , Estudos de Casos e Controles , Volume Expiratório Forçado , Pulmão/fisiopatologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Valores de Referência , Estudos Retrospectivos , Estatísticas não Paramétricas , Fatores de TempoRESUMO
INTRODUCTION: Despite the recent advances in diagnosis and treatment, mortality rates due to infective endocarditis (IE) remain high if not aggressively treated with antibiotics, whether or not associated with surgery. Data on the prevalence, epidemiology and etiology of IE from developing countries remain scarce. The aim of this observational, prospective cohort study was to report a 5-year experience of IE at two teaching hospitals in Rio de Janeiro, Brazil. MATERIAL AND METHODS: Demographical, anamnestic and microbiological characteristics of 71 IE patients were evaluated during the period of January 2009 to March 2013. RESULTS: The mean age of the IE patients was 49.8 ± 2.4 years, of which 41 (57.7%) were males. The median time between the onset of symptoms and diagnosis of IE was 35.8 ± 4.8 days. A total of 31 (43.6%) cases of community-acquired infective endocarditis (CAIE) and 40 (56.3%) cases of healthcare-acquired infective endocarditis (HAIE) were observed. Staphylococcus aureus (30%) was the predominant cause of IE. Streptococcus spp. (45.1 %) was the predominant cause of the CAIE while S. aureus (32.5%) and Enterococcus spp. (27.2 %) were the main etiological agents of HAIE. For 64 (90.1 %) patients with native valve endocarditis, the mitral valve was the most commonly affected (48.3%). The main source of IE in this cohort was intravascular catheter. The tricuspid valve and renal chronic insufficiency were more frequent in patients with HAIE than CAIE (p = 0.001). The risk factors associated with in-hospital mortality rate (46.4%) in IE patients were: age over 45 (OR 3.4; 95% CI 1.03-11.24; p = 0.04) and chronic renal insufficiency (OR 38.3; 95% CI 3.2-449.4; p = 0.004). CONCLUSIONS: At two main teaching hospitals in Brazil, Streptococcus spp. was the principal pathogen of CAIE while S. aureus and Enterococcus spp. were the most frequent causes of HAIE. IE remains a serious disease associated with high in-hospital mortality rate (46.6%); especially, in individuals over 45 years of age and with renal failure. Data suggest that early surgery may improve the outcome of IE patients.
Assuntos
Bactérias/isolamento & purificação , Infecções Bacterianas/mortalidade , Endocardite/mortalidade , Mortalidade Hospitalar , Adulto , Infecções Bacterianas/microbiologia , Brasil/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/mortalidade , Infecção Hospitalar/microbiologia , Infecção Hospitalar/mortalidade , Endocardite/microbiologia , Feminino , Hospitais de Ensino/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de RiscoRESUMO
Staphylococcus aureus is the main causal pathogen of infective endocarditis (IE), which may have distinct origins, namely, community, nosocomial, or non-nosocomial healthcare-associated (NNHCA). We report the first case of NNHCA-IE caused by methicillin-resistant S. aureus strain USA400/SCCmec IV in which the combination therapy of rifampin and vancomycin had a favorable outcome for the patient.
Assuntos
Endocardite/diagnóstico , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/diagnóstico , Adulto , Antibacterianos/administração & dosagem , Brasil , Ecocardiografia Transesofagiana , Endocardite/tratamento farmacológico , Endocardite/microbiologia , Endocardite/patologia , Genótipo , Instalações de Saúde , Humanos , Masculino , Tipagem Molecular , Rifampina/administração & dosagem , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/patologia , Resultado do Tratamento , Vancomicina/administração & dosagemRESUMO
AIMS: To examine the occurrence of and to determine the antimicrobial susceptibility of Corynebacterium pseudodiphtheriticum among patients with bacterial infections at a teaching hospital. METHODS AND RESULTS: A total of 113 Coryne. pseudodiphtheriticum strains identified by conventional biochemical methods and API-Coryne System were recovered from patients from different age groups: 65.48% adults (18 to < or =59 years old), 9.73% aged (> or =60 years old); 14.15% infants (<18 years old); 4.42% newborns (0-7 days). Micro-organisms were mostly related to infections in the urinary (29.2%) and respiratory tracts (27.45%) and intravenous sites (18.6%). Clinical samples were obtained only from 32.7% patients (26 adults, four aged, four infants and three newborns) presenting at least one of the predisposing conditions: end-stage renal disease; renal transplant; AIDS and Mycobacterium tuberculosis infection; cancer, hepatic cirrhosis; haemodialysis and catheter use. Antimicrobial susceptibility tests identified multiresistant phenotypes. Most strains (>50%) were resistant to oxacillin, erythromycin and clindamycin. CONCLUSIONS: Despite significant differences in age and functional status of patients Coryne. pseudodiphtheriticum may be implicated as a cause of respiratory and nonrespiratory human infections. SIGNIFICANCE AND IMPACT OF THE STUDY: Data are valuable for practitioners indicating the occurrence of multiresistant phenotypes and the possibility of severe infections due to Coryne. pseudodiphtheriticum, a pathogen usually overlooked in emerging countries.
Assuntos
Antibacterianos/farmacologia , Infecções por Corynebacterium/epidemiologia , Infecções por Corynebacterium/microbiologia , Corynebacterium/efeitos dos fármacos , Corynebacterium/isolamento & purificação , Hospitais de Ensino/estatística & dados numéricos , Adolescente , Adulto , Idoso , Brasil/epidemiologia , Criança , Pré-Escolar , Corynebacterium/classificação , Farmacorresistência Bacteriana , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/microbiologia , Infecções Urinárias/epidemiologia , Infecções Urinárias/microbiologia , Adulto JovemRESUMO
As Pseudomonas aeruginosa ExoU possesses two functional blocks of homology to calcium-independent (iPLA(2)) and cytosolic phospholipase A(2) (cPLA(2)), we addressed the question whether it would exhibit a proinflammatory activity by enhancing the synthesis of eicosanoids by host organisms. Endothelial cells from the HMEC-1 line infected with the ExoU-producing PA103 strain exhibited a potent release of arachidonic acid (AA) that could be significantly inhibited by methyl arachidonyl fluorophosphonate (MAFP), a specific PLA(2) inhibitor, as well as significant amounts of the cyclooxygenase (COX)-derived prostaglandins PGE(2) and PGI(2). Cells infected with an isogenic mutant defective in ExoU synthesis did not differ from non-infected cells in the AA release and produced prostanoids in significantly lower concentrations. Infection by PA103 induced a marked inflammatory response in two different in vivo experimental models. Inoculation of the parental bacteria into mice footpads led to an early increase in the infected limb volume that could be significantly reduced by inhibitors of both COX and lipoxygenase (ibuprofen and NDGA respectively). In an experimental respiratory infection model, bronchoalveolar lavage (BAL) from mice instilled with 10(4) cfu of PA103 exhibited a marked influx of inflammatory cells and PGE(2) release that could be significantly reduced by indomethacin, a non-selective COX inhibitor. Our results suggest that ExoU may contribute to P. aeruginosa pathogenesis by inducing an eicosanoid-mediated inflammatory response of host organisms.
Assuntos
Eicosanoides/biossíntese , Infecções por Pseudomonas/metabolismo , Pseudomonas aeruginosa/fisiologia , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Ácido Araquidônico/antagonistas & inibidores , Ácido Araquidônico/metabolismo , Ácidos Araquidônicos/farmacologia , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/metabolismo , Linhagem Celular , Dinoprostona/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/microbiologia , Epoprostenol/metabolismo , Feminino , Fosfolipases A2 do Grupo IV , Humanos , Ibuprofeno/uso terapêutico , Indometacina/uso terapêutico , Inflamação/patologia , Inibidores de Lipoxigenase/uso terapêutico , Masoprocol/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Organofosfonatos/farmacologia , Fosfolipases A/antagonistas & inibidores , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/patologia , Pseudomonas aeruginosa/patogenicidadeRESUMO
AIMS: To investigate phenotypic aspects including biotyping, drug susceptibility and production of extracellular enzymes and genetic diversity of Stenotrophomonas maltophilia clinical strains obtained from seven hospitals in Rio de Janeiro, Brazil. METHODS AND RESULTS: Thirty-nine S. maltophilia strains were investigated by biotying, susceptibility testing, extracellular enzymes detection and by randomly amplified polymorphic DNA (RAPD)-PCR. Biotyping distinguished 13 biotypes among 39, and one of them was prevalent. The majority of the strains produced DNase, gelatinase and haemolysin. Protease, lipases and phospholipase C activities were observed in highly variable amounts. None of the strains was elastase producer. The percentage of full susceptibility, by agar dilution, was 100, 94.8, 81.6 and 26.3% for trimethoprim/sulphametoxazole, ticarcillin/clavulanate, ciprofloxacin and ceftazidime, respectively. Thirty-three RAPD-PCR profiles were obtained suggesting multiple sources of acquisition. CONCLUSIONS: The results pointed out the necessity of monitoring S. maltophilia especially in critical hospital wards, to assure effective control measures. SIGNIFICANCE AND IMPACT OF THE STUDY: Despite of the genetic diversity among the strains, in two situations it was observed indistinguishable RAPD-PCR profiles among strains isolated from different patients who had been hospitalized in the same hospital ward, suggesting the possibility of nosocomial transmission that until now has been rarely related.
Assuntos
Stenotrophomonas maltophilia/genética , Animais , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana/métodos , Brasil , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , DNA Bacteriano/análise , Farmacorresistência Bacteriana , Endopeptidases/metabolismo , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/prevenção & controle , Hemólise/fisiologia , Humanos , Fenótipo , Filogenia , Reação em Cadeia da Polimerase/métodos , Polimorfismo Genético/genética , Coelhos , Ovinos , Stenotrophomonas maltophilia/efeitos dos fármacos , Stenotrophomonas maltophilia/enzimologiaRESUMO
Bacteria of Stenotrophomonas maltophilia have been isolated with increasing frequency from the airways of cystic fibrosis (CF) patients, usually following P. aeruginosa infections, but their adherence to human epithelial respiratory cells has never been investigated. In this study, various S. maltophilia strains were seen to adhere to epithelial respiratory cells in vitro, mainly along intercellular junctions. Bacteria could also enter into host cells, as determined by the gentamicin exclusion assay and transmission electron microscopy. Cells co-incubated with P. aeruginosa and S. maltophilia exhibited a significantly decreased adherence of these latter bacteria. No decrease in S. maltophilia adherence was observed when co-infection was carried out with heat-killed P. aeruginosa or when respiratory cells were first incubated with P. aeruginosa, before incubation with S. maltophilia. Our data suggest that P. aeruginosa infections do not account for the increased prevalence of S. maltophilia in CF patient airways, that thermolabile products from P. aeruginosa can control the adherence of S. maltophilia to respiratory cells and also that these two bacteria do not compete for cell receptors.
Assuntos
Aderência Bacteriana , Mucosa Respiratória/microbiologia , Stenotrophomonas maltophilia/patogenicidade , Brônquios/citologia , Brônquios/microbiologia , Fibrose Cística/microbiologia , Células Epiteliais/citologia , Células Epiteliais/microbiologia , Humanos , Junções Intercelulares/microbiologia , Pseudomonas aeruginosa/patogenicidade , Mucosa Respiratória/citologiaRESUMO
Release of lactate dehydrogenase (LDH) from the cytoplasmic compartment, trypan blue exclusion and methylthiazole tetrazolium (MTT) colorimetric assays were compared with regard to their sensitivity in detecting damage of human cultured epithelial cells induced by sodium fluoride or puromycin. LDH assay did not detect any difference between controls and cells treated with either of the two drugs. Cell monolayers treated with 0.3 sodium fluoride or 10(-2) M puromycin presented higher percentages of cells that took up the trypan blue dye than controls but monolayers treated with lower drug concentrations did not differ from controls. Viability measured by MTT assay was the most sensitive assay, detecting a dose-dependent impairment of cell function after treatment with the two drugs. Moreover, MTT offered major advantages in speed, simplicity and precise quantitation over the other viability assays
Assuntos
Humanos , Animais , Técnicas de Cultura de Células , Fígado/citologia , Sobrevivência Celular , Chlorocebus aethiops , Corantes , L-Lactato Desidrogenase , Mamíferos , Sais de Tetrazólio , Tiazóis , Azul Tripano , Células VeroRESUMO
Release of lactate dehydrogenase (LDH) from the cytoplasmic compartment, trypan blue exclusion and methylthiazole tetrazolium (MTT) colorimetric assays were compared with regard to their sensitivity in detecting damage of human cultured epithelial cells induced by sodium fluoride or puromycin. LDH assay did not detect any difference between controls and cells treated with either of the two drugs. Cell monolayers treated with 0.3 sodium fluoride or 10(-2) M puromycin presented higher percentages of cells that took up the trypan blue dye than controls but monolayers treated with lower drug concentrations did not differ from controls. Viability measured by MTT assay was the most sensitive assay, detecting a dose-dependent impairment of cell function after treatment with the two drugs. Moreover, MTT offered major advantages in speed, simplicity and precise quantitation over the other viability assays
Assuntos
Humanos , Animais , Estudo Comparativo , Técnicas de Cultura de Células/métodos , Fígado/citologia , Chlorocebus aethiops , Sobrevivência Celular , Corantes , L-Lactato Desidrogenase/metabolismo , Mamíferos , Sais de Tetrazólio , Tiazóis , Azul Tripano , Células VeroRESUMO
The tracheobronchial secretions from patients with cystic fibrosis often contain high amounts of free proteases. To evaluate whether human leucocyte elastase (HLE) can favour the persistence of bacterial airways infection, we exposed the frog palate mucosa to HLE and then to radiolabelled Pseudomonas aeruginosa and followed the sequence of events by scanning electronmicroscopy. In response to HLE there was a marked outpouring of mucus and a desquamation of the epithelium. P. aeruginosa was shown to adhere to recently secreted granules of mucus and to the exposed submucosal underlying connective tissues. For the eight different bacterial strains studied, a significative adherence to HLE-injured mucosa was observed only in strains that possessed internal haemagglutinating activity. Neither the presence of fimbriae, nor of the mucoid exopolysaccharide, nor of the bacterial surface haemagglutinating activity could be related to adherence of P. aeruginosa to the injured mucosa. These results support the hypothesis that HLE enhances bacterial infection of the respiratory mucosa both by inducing mucus hypersecretion and by exposing receptors to the microbial adhesins. It is also suggested that P. aeruginosa internal lectins may be implicated in adherence to host tissues.
Assuntos
Aderência Bacteriana , Elastase Pancreática/metabolismo , Pseudomonas aeruginosa/fisiologia , Sistema Respiratório/microbiologia , Animais , Epitélio/microbiologia , Epitélio/ultraestrutura , Fímbrias Bacterianas/ultraestrutura , Hemaglutininas/análise , Elastase de Leucócito , Microscopia Eletrônica de Varredura , Mucosa/microbiologia , Mucosa/ultraestrutura , Muco/metabolismo , Palato/microbiologia , Palato/ultraestrutura , Pseudomonas aeruginosa/análise , Pseudomonas aeruginosa/ultraestrutura , Ranidae , Sistema Respiratório/metabolismo , Sistema Respiratório/ultraestrutura , Especificidade da EspécieRESUMO
Several immunodeficiency disorders result from phagocytic or intracellular killing defects. Evaluation is frequently impaired by the complexity of available tests. A new and simple method is presented for the evaluation of the phagocytic and intracellular killing activity by peripheral blood leukocytes, using a small blood volume. Normal individuals show a phagocytic index of 61.4 +/- 16.9% (range 44.5 - 78.3%) after 2 h and 73.1 +/- 13.0% (range 60.1 - 86.1%) after 3 h incubation. For the same incubation periods, the intracellular killing indices were 84.6 +/- 11.0% (range 73.6 - 95.6%) and 88.3 +/- 11.6%) (76.7 -99.9%), respectively.
Assuntos
Células Matadoras Naturais/fisiologia , Fagocitose , Laranja de Acridina , Adolescente , Adulto , Feminino , Humanos , Masculino , Neutrófilos/fisiologiaRESUMO
The cellular and humoral immunity of 15 patients with recurrent urinary tract infections was assessed during infection. We determined the reactivity of peripheral blood lymphocytes to microbial antigens (PPD, streptolysin O, tetanus toxoid, Salmonella typhi and Escherichia coli), to allogenic cells, and to mitogens (phytohemagglutinin, concanavalin A, pokeweed mitogen and jacalin). T and B cells were counted by the rosette technique. We also evaluated serum immunoglobulins and C3 and C4 levels by radial immunoprecipitation and specific antibodies for the etiological agent by direct agglutination, hemagglutination and indirect immunofluorescence. Urinary antibodies were assessed by the antibody-coated bacteria test (ACB). Some patients were retested for cellular immune function after cure. No significant alteration of immunoglobulin levels was detected, except for two patients who showed elevated IgM levels. C3 and C4 were elevated in one and in five cases, respectively. Specific serum antibodies for the etiological agent were present in all patients but their levels did not differ from those of normal controls. In only five patients were urinary antibodies detected by the ACB test. Patients' peripheral blood lymphocyte reactivity was depressed during infection for most of the microbial antigens and mitogens tested and returned to normal levels after cure. T and B cell numbers were within the normal range.