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1.
Clin Microbiol Infect ; 21(1): 35-42, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25636925

RESUMO

Streptococcus pneumoniae is an important cause of acute otitis media (AOM). The aim of this study was to evaluate trends in antibiotic resistance and circulating serotypes of pneumococci isolated from middle ear fluid of French children with AOM during the period 2001-2011, before and after the introduction of the PCV-7 (2003) and PCV-13 (2010) vaccines. Between 2001 and 2011 the French pneumococcal surveillance network analysed the antibiotic susceptibility of 6683 S. pneumoniae isolated from children with AOM, of which 1569 were serotyped. We observed a significant overall increase in antibiotic susceptibility. Respective resistance (I+R) rates in 2001 and 2011 were 76.9% and 57.3% for penicillin, 43.0% and 29.8% for amoxicillin, and 28.6% and 13.0% for cefotaxime. We also found a marked reduction in vaccine serotypes after PCV-7 implementation, from 63.0% in 2001 to 13.2% in 2011, while the incidence of the additional six serotypes included in PCV-13 increased during the same period, with a particularly high proportion of 19A isolates. The proportion of some non-PCV-13 serotypes also increased between 2001 and 2011, especially 15A and 23A. Before PCV-7 implementation, most (70.8%) penicillin non-susceptible pneumococci belonged to PCV-7 serotypes, whereas in 2011, 56.8% of penicillin non-susceptible pneumococci belonged to serotype 19A. Between 2001 and 2011, antibiotic resistance among pneumococci responsible for AOM in France fell markedly, and PCV-7 serotypes were replaced by non-PCV-7 serotypes, especially 19A. We are continuing to assess the impact of PCV-13, introduced in France in 2010, on pneumococcal serotype circulation and antibiotic resistance.


Assuntos
Farmacorresistência Bacteriana , Otite Média/epidemiologia , Otite Média/microbiologia , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/efeitos dos fármacos , Antibacterianos/farmacologia , França/epidemiologia , Humanos , Incidência , Testes de Sensibilidade Microbiana , Otite Média com Derrame/microbiologia , Vacinas Pneumocócicas , Sorogrupo
2.
Clin Microbiol Infect ; 16(4): 379-84, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19519843

RESUMO

The usefulness of two quantitative real-time PCR assays (qrt-PCRmip targeting Legionella pneumophila, and qrt-PCR16S targeting all Legionella species) performed on lower respiratory tract (LRT) samples for diagnostic and prognostic purposes in 311 patients hospitalized for community-acquired pneumonia (CAP) in Rhône-Alpes (France) was evaluated. The Now Legionella urinary antigen test (UAT) from Binax (Portland, ME, USA) was used as a reference test. Samples were divided into two groups. Group A included 255 CAP patients admitted to Chambery hospital in 2005 and 2006. The Now Legionella UAT was positive in 14 patients. Sensitivities, specificities, positive predictive and negative predictive values for both qrt-PCR tests were 63.6, 98.7, 77.7 and 97.4%, respectively. Group B included 56 consecutive legionellosis patients diagnosed during a 4-year period (2003-2006) at the Grenoble University Hospital. The qrt-PCR16S and qrt-PCRmip displayed a sensitivity of 82.14 and 80.4%, respectively. Among the 70 legionellosis cases, L. pneumophila serogroup 1 was isolated in 15; qrt-PCRmip was positive in another 36, suggesting L. pneumophila infection, whereas the Legionella species involved could not be determined in the remaining 19 cases. The Legionella burden in LRT samples at the time of admission was determined in 46 patients using qrt-PCR16S tests, 44 for qrt-PCR mip groups A and B patients. It varied from 1.9 to 8.35 log(10) DNA copies/mL of LRT sample for qrt-PCR16S and from 1.9 to 8.11 log(10) DNA copies/mL of sample for qrt-PCRmip. High bacterial loads in LRT samples at hospital admission were significantly associated with higher Fine classes, the need for hospitalization in an intensive care unit and for prolonged hospitalization.


Assuntos
Legionelose/diagnóstico , Reação em Cadeia da Polimerase/métodos , Adolescente , Adulto , Idoso , Infecções Comunitárias Adquiridas/microbiologia , DNA Bacteriano/análise , Humanos , Legionella/genética , Pessoa de Meia-Idade , Pneumonia/microbiologia , Sensibilidade e Especificidade , Adulto Jovem
3.
Eur J Clin Microbiol Infect Dis ; 28(9): 1105-11, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19449044

RESUMO

The purpose of this study was to evaluate the possibility of using a semi-automated repetitive DNA sequences-based polymerase chain reaction (rep-PCR) for typing Pseudomonas aeruginosa isolates. rep-PCR profiles obtained by the DiversiLab system of 84 P. aeruginosa isolates from distinct epidemiological situations were obtained. rep-PCR groupings were in good agreement with the origin of these isolates. Linked rep-PCR profiles were observed for isolates recovered from a same family of cystic fibrosis (CF) patients, for the etiological agents of clustered cases of nosocomial infections, and for some isolates recovered from a same hospital room. rep-PCR and pulsed-field gel electrophoresis SpeI restricted genomic DNA (PFGE-SpeI) profiles were compared. In a few instances, rep-PCR revealed genetic divergences among isolates of a same group of PFGE-SpeI profiles. These divergences could reflect genetic drifts among closely related isolates, as illustrated by those observed between clinical and environmental isolates of a same group of PFGE-SpeI profiles. The interpretation of such differences will require further studies, but the rep-PCR analysis of P. aeruginosa diversity appeared to be an appropriate method to investigate infra-specific genetic relatedness.


Assuntos
Automação/métodos , Técnicas de Tipagem Bacteriana/métodos , Impressões Digitais de DNA/métodos , Reação em Cadeia da Polimerase/métodos , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/genética , DNA Bacteriano/genética , Humanos , Sequências Repetitivas Dispersas , Epidemiologia Molecular/métodos , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa/isolamento & purificação
4.
Rev Mal Respir ; 26(3): 283-90, 2009 Mar.
Artigo em Francês | MEDLINE | ID: mdl-19367202

RESUMO

INTRODUCTION: In the context of reducing endoscopy-related infectious risk and new national guidelines on microbiological samples from bronchoscopy, the results of a surveillance program set up in a hospital center were analyzed. METHODS: Over 4 years, scheduled samples were taken from disinfected bronchoscopes. Bacteriology and mycology tests were used to search for microorganisms. The results were interpreted as falling within three levels: target, alert, and action. Factors that could explain the contamination were studied: age of the bronchoscope, number of uses per year, brand, and model. RESULTS: Out of 96 scheduled samples taken, the compliance rate for the period was 83% and increased (p=0.06) over the 4 years. We identified 15 Pseudomonas (six aeruginosa and nine other species), one Stenotrophomonas, one enterobacterium, and two filamentous fungi. None of the factors studied had a significant effect on sample contamination. CONCLUSION: The microbiological surveillance of bronchoscopes is an indispensable part of the quality assurance of bronchoscope maintenance. It can lead to maintenance of the bronchoscope when a noncompliant result is found.


Assuntos
Broncoscópios/microbiologia , Contaminação de Equipamentos , Humanos , Garantia da Qualidade dos Cuidados de Saúde
6.
Pathol Biol (Paris) ; 56(5): 272-8, 2008 Jul.
Artigo em Francês | MEDLINE | ID: mdl-18178021

RESUMO

OBJECTIVE: Analyze the microbiological quality of reconstituted milk formulas and the surface hygiene in a hospital infant formula room, in the context of a worldwide emergence of Enterobacter sakazakii infections. MATERIAL AND METHODS: Over 3.5 years, monthly samples of reconstituted milk formulas as well as quarterly infant formula room surface samples were taken for bacteriological analysis. RESULTS: Of the 156 formulas analyzed, 54 carried microorganisms but no pathogenic bacteria. The presence of Bacillus species was found in 54% of the formulas for premature infants and in 19% of the other formulas (significant difference). Bacteria, probably brought by operators during reconstitution of the powdered formulas, were found in four of 156 samples (two negative-coagulase staphylococcus, one alpha-hemolytic streptococcus, and one Clostridium bifermentans). Surfaces were studied using 117 samples divided into 11 series: 4.3% of the points carried pathogenic bacteria (Enterobacter cloacae, Pseudomonas fluorescens, Bulhkholderia cepacia, Staphylococcus aureus). DISCUSSION: The presence of Bacillus species should be analyzed thoroughly so as to differentiate Bacillus cereus from other nonpathogenic species. The microbiological analysis techniques used for reconstituted infant formulas can be simplified. CONCLUSION: The quality of the infant formulas seems satisfactory. Hygiene practices provide good microbiological quality in reconstituted infant milk formulas. Microbiological monitoring of these preparations and the infant formula room surfaces is an important aspect of the quality assurance policy, which makes it possible to take corrective measures when an unsatisfactory result is found.


Assuntos
Monitoramento Ambiental , Contaminação de Equipamentos , Microbiologia de Alimentos , Serviço Hospitalar de Nutrição , Fórmulas Infantis , Leite/microbiologia , Animais , Bacillus/isolamento & purificação , Cronobacter sakazakii/isolamento & purificação , Infecção Hospitalar/prevenção & controle , Infecções por Enterobacteriaceae/prevenção & controle , Humanos , Recém-Nascido , Doenças do Prematuro/prevenção & controle , Lactobacillus/isolamento & purificação , Pós , Staphylococcus aureus/isolamento & purificação
7.
Med Mal Infect ; 37(11): 762-4, 2007 Nov.
Artigo em Francês | MEDLINE | ID: mdl-17888603

RESUMO

We report a case of severe pneumonia due to Chryseobacterium indologenes in an immunocompetent patient. Chryseobacterium indologenes (formerly Flavobacterium indologenes) are saprophytic Gram-negative rods widely distributed in damp environment. Many sites of infection were described in the literature. These infections are always severe sometimes associated to multiple organ failure. The evolution is usually favorable with antibiotic treatment. Bacteria characteristically grow as yellow-pigmented colonies. They are naturally resistant to many antimicrobial agents. They are usually susceptible to piperacillin(DCI) alone or combined with tazobactam(DCI), ceftazidime(DCI), cefepime(DCI), fluoroquinolones(DCI), rifampin(DCI) and cotrimoxazole(DCI), but the in vitro susceptibility to these antibiotics should be systematically tested. Nevertheless, the optimum antibiotic treatment for Chryseobacterium-related infections remains to be established. In the case we report, the diagnosis was made according to the results of bronchial sample bacterial culture. This case report underlines the need for specific management of patients infected with this species.


Assuntos
Antibacterianos/uso terapêutico , Chryseobacterium , Infecções por Flavobacteriaceae/imunologia , Imunocompetência , Adulto , Chryseobacterium/efeitos dos fármacos , Chryseobacterium/isolamento & purificação , Feminino , Humanos , Testes de Sensibilidade Microbiana
8.
Arch Pediatr ; 14(11): 1298-303, 2007 Nov.
Artigo em Francês | MEDLINE | ID: mdl-17631988

RESUMO

UNLABELLED: Several studies have reported an increasing incidence of childhood parapneumonic empyemas in various countries. AIM OF THE STUDY: The aim of our study was to estimate the annual incidence of complicated community-acquired pneumonias in children during a 9-year period in a French area and to describe the epidemiological and clinical characteristics of these complications. POPULATION AND METHODS: We have listed the children from 28 days to 15 years old, hospitalized in the 2 children hospitals of the Isere district for a community-acquired pneumonia complicated with a pleural empyema or a pulmonary abscess from 1995 to 2003. RESULTS: During the study period, 90 children were hospitalized for a complicated pneumonia including 83 pleural empyemas and 7 isolated lung abscess. The average number of cases was 4 per year from 1995 to 1998 then increased since 1999 to reach 34 cases in 2003, according to a linear model (P<0,001). The incidence of the complicated pneumonia, plotted to the paediatric population of the area has gone up from 0.5 per 100000 to 13 per 100000 children between 1995 and 2003. CONCLUSION: The incidence of the complicated pneumonias in children increased since 1999 in a French area. Additional investigations are necessary to identify the causes of this increase.


Assuntos
Empiema Pleural/epidemiologia , Pneumonia Bacteriana/epidemiologia , Abscesso/epidemiologia , Abscesso/microbiologia , Abscesso/terapia , Adolescente , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/terapia , Empiema Pleural/diagnóstico , Empiema Pleural/microbiologia , Empiema Pleural/terapia , Feminino , França/epidemiologia , Humanos , Lactente , Recém-Nascido , Masculino , Pneumonia Bacteriana/terapia , Estudos Retrospectivos
9.
Infect Control Hosp Epidemiol ; 28(5): 625-8, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17464930
10.
Med Mal Infect ; 37(5): 290-2, 2007 May.
Artigo em Francês | MEDLINE | ID: mdl-17336015

RESUMO

Pneumococcal cellulitis is an uncommon infection. Head, neck, and trunk are usually affected in patients with hematological malignancies and lupus erythematosus. Limb cellulitis is frequently observed in patients with diabetes mellitus, drug abusers, or alcoholics. Patients present with septic shock most of the time. Surgical treatment is necessary in 50% of the cases. The outcome is usually favorable. We describe the case of a 72-year-old alcoholic patient with diabetes mellitus presenting with cellulitis and septic shock. Serotype 19 Streptococcus pneumoniae with abnormal susceptibility to penicillin (MIC: 0.75 mg/l) was isolated from cellulitis and in blood culture. The evolution was favorable after itavenous antibiotherapy combining ceftriaxone(DCI) (2 g/j), metronidazole(DCI) (1 g/j), and ciprofloxacin(DCI).


Assuntos
Celulite (Flegmão)/microbiologia , Complicações do Diabetes/microbiologia , Infecções Pneumocócicas/diagnóstico , Infecções Pneumocócicas/tratamento farmacológico , Streptococcus pneumoniae/isolamento & purificação , Idoso , Ceftriaxona/uso terapêutico , Celulite (Flegmão)/tratamento farmacológico , Ciprofloxacina/uso terapêutico , Humanos , Masculino , Metronidazol/uso terapêutico , Testes de Sensibilidade Microbiana , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/efeitos dos fármacos
11.
J Clin Microbiol ; 45(6): 1673-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17392442

RESUMO

Acute postoperative endophthalmitis caused by Staphylococcus lugdunensis is infrequently reported in clinical studies. Five cases of acute postcataract surgery endophthalmitis caused by S. lugdunensis were taken from a multicenter prospective study conducted in four university-affiliated hospitals in France (2004 to 2005). These cases were characterized by severe ocular inflammation occurring with a mean delay of 7.6 days after cataract surgery, severe visual loss (hand motions or less in three cases), and dense infiltration of the vitreous. Each of these patients was initially treated by using a standard protocol with intravitreal (vancomycin and ceftazidime), systemic, and topical antibiotics. Given the severity of the endophthalmitis, even though bacteria were sensitive to intravitreal antibiotics, pars plana vitrectomy was needed in four cases. The final visual prognosis was complicated by severe retinal detachment in three cases. The microbiological diagnosis was reached by using conventional cultures with specific biochemical tests and eubacterial PCR amplification followed by direct sequencing.


Assuntos
Extração de Catarata/efeitos adversos , Endoftalmite , Reação em Cadeia da Polimerase/métodos , Complicações Pós-Operatórias , Staphylococcus/isolamento & purificação , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Meios de Cultura , Endoftalmite/diagnóstico , Endoftalmite/tratamento farmacológico , Endoftalmite/microbiologia , Infecções Oculares Bacterianas/diagnóstico , Infecções Oculares Bacterianas/tratamento farmacológico , Infecções Oculares Bacterianas/microbiologia , Feminino , França , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus/classificação , Staphylococcus/genética
12.
J Fr Ophtalmol ; 30(10): 1049-59, 2007 Dec.
Artigo em Francês | MEDLINE | ID: mdl-18268447

RESUMO

The microbiological study identifies the bacterial spectrum after surgery, in acute, delayed-onset, or chronic endophthalmitis. DNA amplification of eubacterium-specific sequences in DNA extracted from ocular samples is a new tool for the etiological diagnosis of endophthalmitis. The most successful way to identify bacteria in endophthalmitis is the association of conventional cultures and panbacterial PCR on vitreous samples. Both techniques are complementary. The efficacy of these new molecular techniques should modify our future therapeutic strategies.


Assuntos
Infecções Bacterianas/diagnóstico , Endoftalmite/diagnóstico , Ferimentos Oculares Penetrantes/complicações , Infecção da Ferida Cirúrgica/diagnóstico , Doença Aguda , Humor Aquoso/microbiologia , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Técnicas Bacteriológicas , Endoftalmite/tratamento farmacológico , Endoftalmite/microbiologia , Eubacterium/genética , Eubacterium/isolamento & purificação , Ferimentos Oculares Penetrantes/microbiologia , Infecções por Bactérias Gram-Positivas/diagnóstico , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Análise de Sequência de DNA , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/microbiologia , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/microbiologia , Infecção da Ferida Cirúrgica/tratamento farmacológico , Infecção da Ferida Cirúrgica/microbiologia , Vitrectomia , Corpo Vítreo/microbiologia
14.
Pathol Biol (Paris) ; 50(10): 595-8, 2002 Dec.
Artigo em Francês | MEDLINE | ID: mdl-12504368

RESUMO

In 1999, in Rhône-Alpes region, in a survey of resistance to antibiotics of Streptococcus pneumoniae, 35 cases of meningitis were observed. A retrospectic questionnary was sent to each participant. MICs to Penicillin, Amoxicillin and Cefotaxime were determined with ATB-PNEUMO gallery or E-test and by disk diffusion for the other antibiotics. The results were interpreted according to the recommendations of the CA-SFM. Mean age was 38.1 years (range : 1 month -78 years) and sex-ratio 2/5. Eight patients had previously received antibiotics, 22 patients had risk factors and 23 were transferred in intensive care unit. The patients received C3G + glycopeptide in 15 of 16 children and in 13/19 adults according to the consensus recommendations. Diagnostic was made on the direct examination of CSF in 83%, and blood cultures was positive in 74.3% of cases. The percentage of PRP was 48.6% with 17.1% of intermediate-amoxicilline and 14.3% intermediate-cefotaxime strains. Resistance to trimethoprim-sulfamethoxazole was 45.7%, to chloramphenicol 30% and to fosfomycin 6.9%. All the strains were susceptible to rifampicin and vancomycin. Among the 17 PRP strains, 7 were belonging to serotype 6 (6 in children). The clinical outcome was fatal in 7 male cases (20%), without risk factors in 3 children and 6 of 7 strains were susceptible to penicillin. Six patients (17%) had auditive and/or neurologic sequellaes. This study shows that nearly 50% of strains isolated in meningitis, in Rhône-Alpes region, were not susceptible to penicillin, and confirms the frequency of sequellaes while the mortality is not related with the resistance of strains to the antibiotics.


Assuntos
Meningite Pneumocócica/epidemiologia , Adolescente , Adulto , Idoso , Amoxicilina/administração & dosagem , Cefotaxima/administração & dosagem , Criança , Pré-Escolar , Cloranfenicol , Resistência Microbiana a Medicamentos , Feminino , Fosfomicina , França/epidemiologia , Humanos , Lactente , Masculino , Meningite Pneumocócica/diagnóstico , Meningite Pneumocócica/tratamento farmacológico , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Penicilinas/administração & dosagem , Estudos Retrospectivos , Rifampina/administração & dosagem , Inquéritos e Questionários , Combinação Trimetoprima e Sulfametoxazol , Vancomicina/administração & dosagem
15.
Clin Microbiol Infect ; 8(10): 680-3, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12390289

RESUMO

Screening by ofloxacin disk was carried out on 1158 strains of Streptococcus pneumoniae in order to investigate the in vitro bacteriostatic activity of penicillin G, levofloxacin, moxifloxacin, telithromycin, linezolid, pristinamycin and quinupristin-dalfopristin against ofloxacin-intermediate and -resistant S. pneumoniae strains. It was concluded that these new antimicrobial agents could be useful for the treatment of pneumococcal infections caused by penicillin-sensitive and -resistant S. pneumoniae, and would represent a valid therapeutic option for patients allergic to beta-lactams, should they prove to be potent in vivo.


Assuntos
Antibacterianos/farmacologia , Compostos Aza , Fluoroquinolonas , Cetolídeos , Levofloxacino , Macrolídeos , Ofloxacino/farmacologia , Quinolinas , Streptococcus pneumoniae/efeitos dos fármacos , Virginiamicina/análogos & derivados , Acetamidas/farmacologia , Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana , Lactamas/imunologia , Linezolida , Testes de Sensibilidade Microbiana , Moxifloxacina , Ofloxacino/imunologia , Oxazolidinonas/farmacologia , Penicilina G/farmacologia , Pristinamicina/farmacologia , Streptococcus pneumoniae/patogenicidade , Virginiamicina/farmacologia
17.
Pathol Biol (Paris) ; 49(7): 548-52, 2001 Sep.
Artigo em Francês | MEDLINE | ID: mdl-11642017

RESUMO

In 1999, during the survey of resistance of Streptococcus pneumoniae to antibiotics by 31 clinical laboratories of Rhône-Alpes area, MIC to penicillin (P), amoxicillin (AMX) and cefotaxime (CTX) of 877 PRP strains or with a diameter of inhibition to oxacillin inferior to 26 mm, were determined by each institution by E-test (n = 220 strains) or ATB-PNEUMO (n = 657 strains). MICs of these three antibiotics were determined by dilution in agar medium by the coordinating center. The essential agreement was respectively for ATB-PNEUMO and E-test 89% versus 84% for P (p > 0.05), of 86% vs 79% for AMX (p < 0.01), and of 91% vs 86% for CTX (p = 0.03). When the strains were classified in clinical category, the differences were significant (p < 0.001) for AMX (85% vs 71%) and for CTX (82% vs 75%) but not for P (73% vs 78%). ATB-PNEUMO method was more sensitive than E-test for the detection of strains susceptible to P (90 vs 73%), to AMX (83 vs 78%) and to CTX (80 vs 72%) and for the strains intermediate to AMX (90 vs 78%). On the contrary, E-test is more specific than ATB-PNEUMO for the detection of P-resistant strains (94 vs 86%). Finally, the specificity of both methods is the same for detection of P-S, AMX-R and CTX-I strains.


Assuntos
Antibacterianos/farmacologia , Resistência a Medicamentos , Testes de Sensibilidade Microbiana/métodos , Kit de Reagentes para Diagnóstico , Streptococcus pneumoniae/efeitos dos fármacos , Amoxicilina/farmacologia , Cefotaxima/farmacologia , Distribuição de Qui-Quadrado , Humanos , Oxacilina/farmacologia , Resistência às Penicilinas , Infecções Pneumocócicas/microbiologia , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Infect Immun ; 68(5): 2916-24, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10768989

RESUMO

Pseudomonas aeruginosa, an opportunistic pathogen responsible most notably for severe infections in cystic fibrosis (CF) patients, utilizes the type III secretion system for eukaryotic cell intoxication. The CF clinical isolate CHA shows toxicity towards human polymorphonuclear neutrophils (PMNs) which is dependent on the type III secretion system but independent of the cytotoxin ExoU. In the present study, the cytotoxicity of this strain toward human and murine macrophages was demonstrated. In low-multiplicity infections (multiplicity of infection, 10), approximately 40% of the cells die within 60 min. Analysis of CHA-infected cells by transmission electron microscopy, DNA fragmentation assay, and Hoechst staining revealed the hallmarks of oncosis: cellular and nuclear swelling, disintegration of the plasma membrane, and absence of DNA fragmentation. A panel of 29 P. aeruginosa CF isolates was screened for type III system genotype, protein secretion profile, and cytotoxicity toward PMNs and macrophages. This study showed that six CF isolates were able to induce rapid ExoU-independent oncosis on phagocyte cells.


Assuntos
ADP Ribose Transferases/metabolismo , Apoptose , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/metabolismo , Fibrose Cística/microbiologia , Proteínas de Ligação a DNA/metabolismo , Glucosiltransferases/metabolismo , Macrófagos/citologia , Neutrófilos/citologia , Pseudomonas aeruginosa/metabolismo , Transativadores/metabolismo , Animais , Linfócitos B/citologia , Benzimidazóis , Linhagem Celular , Citotoxinas/metabolismo , Fragmentação do DNA , Corantes Fluorescentes , Células HeLa , Humanos , Macrófagos/metabolismo , Camundongos , Microscopia Eletrônica , Neutrófilos/metabolismo , Pseudomonas aeruginosa/isolamento & purificação , Coloração e Rotulagem/métodos , Fatores de Tempo
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