RESUMEN
Glaesserella parasuis (G. parasuis) is a commensal bacterium in the upper respiratory tract of pigs that can also cause the swine Glässer disease, which induces an intensive inflammatory response and results in significant economic losses to the swine industry worldwide. G. parasuis can cause disease through infection of the respiratory tract, resulting in systemic infection, but the mechanism is largely unknown. Recently we showed that Glaesserella parasuis serotype 4 (GPS4) increased swine tracheal epithelial barrier permeability, resulting in easier bacterial translocation. Tight junction proteins (TJ) play a crucial role in maintaining the integrity and impermeability of the epithelial barrier. GPS4 decreased the expression of the TJ ZO-1 and occludin in swine tracheal epithelial cells (STEC). Furthermore, the proinflammatory cytokines IL-6, IL-8 and TNF-α were significantly upregulated in GPS4-infected STEC, and both the MAPK and NF-κB signaling pathways were activated and contributed to the expression of TNF-α. We demonstrate that the production of proinflammatory cytokines, especially TNF-α, during GPS4 infection was involved in barrier dysfunction. Additionally, animal challenge experiments confirmed that GPS4 infection downregulated TJ in the lungs of piglets and induced a severe inflammatory response. In general, G. parasuis infection downregulated the expression of TJ and induced massive secretion of proinflammatory cytokines, resulting in epithelial barrier disruption and favoring bacterial infection. This study allowed us to better understand the mechanism by which G. parasuis crosses the respiratory tract of pigs.
Asunto(s)
Traslocación Bacteriana , Haemophilus parasuis/fisiología , Infecciones por Pasteurellaceae/veterinaria , Transducción de Señal , Enfermedades de los Porcinos/microbiología , Animales , Células Epiteliales , Infecciones por Haemophilus/microbiología , Infecciones por Haemophilus/fisiopatología , Infecciones por Haemophilus/veterinaria , Haemophilus parasuis/genética , Infecciones por Pasteurellaceae/microbiología , Infecciones por Pasteurellaceae/fisiopatología , Serogrupo , Sus scrofa , Porcinos , Enfermedades de los Porcinos/fisiopatologíaRESUMEN
BACKGROUND: Influenza virus infection is often complicated by a bacterial infection, with this coinfection causing severe pneumonia. If not timely treated, the disease can cause death. OBJECTIVE: To demonstrate, in animal models, that coinfection with influenza virus and bacteria that affect the respiratory tract causes multisystemic damage. METHOD: Six groups of mice were formed: a control group, one infected with the influenza virus, two infected with bacteria: Haemophilus influenzae and Streptococcus pneumoniae, respectively; and two co-infected with influenza virus and Haemophilus influenzae or Streptococcus pneumoniae, respectively. RESULTS: Of the six groups of mice, only the group co-infected with influenza virus and Streptococcus pneumoniae showed damage to thoracic and abdominal organs. A decrease in serum cytokine levels was found in all study groups, which was more pronounced in the co-infected mice. CONCLUSIONS: The groups of mice infected with Streptococcus pneumoniae or influenza virus alone showed no damage, which indicates that coexistence of these infections caused the damage in the group of co-infected mice.
ANTECEDENTES: La infección por el virus de la influenza con frecuencia se complica con una infección bacteriana, coinfección que provoca cuadros graves de neumonía, la cual puede ocasionar la muerte si no es tratada en forma oportuna. OBJETIVO: Demostrar en modelos animales que la coinfección por el virus de la influenza y bacterias que afectan el tracto respiratorio ocasiona daño multisistémico. MÉTODO: Se formaron seis grupos de ratones: un grupo control, uno infectado de virus de la influenza, dos infectados de bacterias: Haemophilus influenzae y Streptococcus pneumoniae, respectivamente; y dos coinfectados de virus de la influenza y Haemophilus influenzae y Streptococcus pneumoniae, respectivamente. RESULTADOS: De los seis grupos de ratones, solo en el grupo coinfectado de virus de la influenza y Streptococcus pneumoniae se observó daño en órganos torácicos y abdominales. En todos los grupos se encontró disminución de los niveles séricos de las citocinas, mayor en los ratones coinfectados. CONCLUSIONES: Los grupos de ratones infectados solo de Streptococcus pneumoniae o el virus de la influenza no presentaron daños, lo cual indica que la coexistencia de estas infecciones fue la que ocasionó el daño en el grupo de ratones coinfectados.
Asunto(s)
Infecciones por Haemophilus/fisiopatología , Infecciones por Orthomyxoviridae/fisiopatología , Infecciones Neumocócicas/fisiopatología , Animales , Coinfección/fisiopatología , Citocinas/sangre , Modelos Animales de Enfermedad , Infecciones por Haemophilus/microbiología , Masculino , Ratones , Ratones Endogámicos BALB C , Infecciones por Orthomyxoviridae/virología , Infecciones Neumocócicas/microbiología , Neumonía/microbiología , Neumonía/fisiopatología , Neumonía/virología , Streptococcus pneumoniae/aislamiento & purificaciónRESUMEN
Abstract Background: Influenza virus infection is often complicated by a bacterial infection, with this coinfection causing severe pneumonia. If not timely treated, the disease can cause death. Objective: To demonstrate, in animal models, that coinfection with influenza virus and bacteria that affect the respiratory tract causes multisystemic damage. Method: Six groups of mice were formed: a control group, one infected with the influenza virus, two infected with bacteria: Haemophilus influenzae and Streptococcus pneumoniae, respectively; and two co-infected with influenza virus and Haemophilus influenzae or Streptococcus pneumoniae, respectively. Results: Of the six groups of mice, only the group co-infected with influenza virus and Streptococcus pneumoniae showed damage to thoracic and abdominal organs. A decrease in serum cytokine levels was found in all study groups, which was more pronounced in the co-infected mice. Conclusions: The groups of mice infected with Streptococcus pneumoniae or influenza virus alone showed no damage, which indicates that coexistence of these infections caused the damage in the group of co-infected mice.
Resumen Antecedentes: La infección por el virus de la influenza con frecuencia se complica con una infección bacteriana, coinfección que provoca cuadros graves de neumonía, la cual puede ocasionar la muerte si no es tratada en forma oportuna. Objetivo: Demostrar en modelos animales que la coinfección por el virus de la influenza y bacterias que afectan el tracto respiratorio ocasiona daño multisistémico. Método: Se formaron seis grupos de ratones: un grupo control, uno infectado de virus de la influenza, dos infectados de bacterias: Haemophilus influenzae y Streptococcus pneumoniae, respectivamente; y dos coinfectados de virus de la influenza y Haemophilus influenzae y Streptococcus pneumoniae, respectivamente. Resultados: De los seis grupos de ratones, solo en el grupo coinfectado de virus de la influenza y Streptococcus pneumoniae se observó daño en órganos torácicos y abdominales. En todos los grupos se encontró disminución de los niveles séricos de las citocinas, mayor en los ratones coinfectados. Conclusiones: Los grupos de ratones infectados solo de Streptococcus pneumoniae o el virus de la influenza no presentaron daños, lo cual indica que la coexistencia de estas infecciones fue la que ocasionó el daño en el grupo de ratones coinfectados.
Asunto(s)
Animales , Masculino , Ratas , Infecciones Neumocócicas/fisiopatología , Infecciones por Orthomyxoviridae/fisiopatología , Infecciones por Haemophilus/fisiopatología , Infecciones Neumocócicas/microbiología , Neumonía/fisiopatología , Neumonía/microbiología , Neumonía/virología , Streptococcus pneumoniae/aislamiento & purificación , Citocinas/sangre , Infecciones por Orthomyxoviridae/virología , Modelos Animales de Enfermedad , Coinfección/fisiopatología , Infecciones por Haemophilus/microbiología , Ratones Endogámicos BALB CRESUMEN
BACKGROUND: Knowing the individual child's risk is highly useful when deciding on treatment strategies, especially when deciding on invasive procedures. In this study, we aimed to develop a new predictive score for children with bacterial meningitis and compare this with existing predictive scores and individual risk factors. METHODS: We developed the Meningitis Swedish Survival Score (MeningiSSS) based on a previous systematic review of risk factors. From this, we selected risk factors identified in moderate-to-high-quality studies that could be assessed at admission to the hospital. Using data acquired from medical records of 101 children with bacterial meningitis, we tested the overall capabilities of the MeningiSSS compared with four existing predictive scores using a receiver operating characteristic curve (ROC) analysis to assert the area under the curve (AUC). Finally, we tested all predictive scores at their cut-off levels using a Chi-square test. As outcome, we used a small number of predefined outcomes; in-hospital mortality, 30-day mortality, occurrence of neurological disabilities at discharge defined as Pediatric Cerebral Performance Category Scale category two to five, any type of complications occurring during the hospital stay, use of intensive care, and use of invasive procedures to monitor or manage the intracerebral pressure. RESULTS: For identifying children later undergoing invasive procedures to monitor or manage the intracerebral pressure, the MeningiSSS excelled in the ROC-analysis (AUC = 0.90) and also was the only predictive score able to identify all cases at its cut-off level (25 vs 0%, p < 0.01). For intensive care, the MeningiSSS (AUC = 0.79) and the Simple Luanda Scale (AUC = 0.75) had the best results in the ROC-analysis, whereas others performed less well (AUC ≤ 0.65). Finally, while none of the scores' results were significantly associated with complications, an elevated score on the MeningiSSS (AUC = 0.70), Niklasson Scale (AUC = 0.72), and the Herson-Todd Scale (AUC = 0.79) was all associated with death. CONCLUSIONS: The MeningiSSS outperformed existing predictive scores at identifying children later having to undergo invasive procedures to monitor or manage the intracerebral pressure in children with bacterial meningitis. Our results need further external validation before use in clinical practice. Thus, the MeningiSSS could potentially be helpful when making difficult decisions concerning intracerebral pressure management.
Asunto(s)
Mortalidad Hospitalaria , Hipertensión Intracraneal/diagnóstico , Presión Intracraneal , Meningitis Bacterianas/fisiopatología , Monitoreo Fisiológico , Factores de Edad , Área Bajo la Curva , Temperatura Corporal , Preescolar , Cuidados Críticos , Sistemas de Apoyo a Decisiones Clínicas , Craniectomía Descompresiva , Drenaje , Femenino , Estado Funcional , Infecciones por Haemophilus/complicaciones , Infecciones por Haemophilus/fisiopatología , Infecciones por Haemophilus/terapia , Humanos , Hipertensión Intracraneal/etiología , Hipertensión Intracraneal/fisiopatología , Hipertensión Intracraneal/terapia , Leucopenia/fisiopatología , Masculino , Meningitis Bacterianas/complicaciones , Meningitis Bacterianas/terapia , Meningitis Meningocócica/complicaciones , Meningitis Meningocócica/fisiopatología , Meningitis Meningocócica/terapia , Meningitis Neumocócica/complicaciones , Meningitis Neumocócica/fisiopatología , Meningitis Neumocócica/terapia , Mortalidad , Curva ROC , Síndrome de Dificultad Respiratoria/etiología , Síndrome de Dificultad Respiratoria/fisiopatología , Factores de Riesgo , Convulsiones/etiología , Convulsiones/fisiopatología , Choque/etiología , Choque/fisiopatología , VentriculostomíaRESUMEN
Haemophilus influenzae type b (Hib) conjugate vaccines have led to dramatic reductions in Hib disease among young children worldwide. Nontypeable H. influenzae (NTHi) is now the major cause of invasive H. influenzae infections. We investigated the clinical characteristics of invasive NTHi diseases among children in Japan, to clarify the pathogenicity of isolated NTHi strains. The mortality rate was 10.7%, with deaths occurring mainly among children with underlying comorbidities. Biotypes II and III were the most common, and most strains (64.3%) had multiple amino acid substitutions at the Asp-350, Ser-357, Ser-385, and/or Met-377 sites of penicillin-binding protein 3. Two strains were ß-lactamase positive and ampicillin-clavulanate resistant. Biofilm indices varied widely, and IS1016 was detected in 10.7% of the strains tested. Moreover, there was wide variation in the characteristics of invasive NTHi strains. NTHi strains, showing great genetic diversity, are responsible for most invasive H. influenzae infections in children in the postvaccine era. Continuous monitoring of NTHi strains responsible for invasive diseases in children is important to detect changes in the epidemiology of invasive H. influenzae infections in the postvaccine era.
Asunto(s)
Infecciones por Haemophilus/microbiología , Haemophilus influenzae/clasificación , Haemophilus influenzae/fisiología , Antibacterianos/farmacología , Adhesión Bacteriana/genética , Técnicas de Tipificación Bacteriana , Biopelículas/crecimiento & desarrollo , Niño , Preescolar , Elementos Transponibles de ADN , Farmacorresistencia Bacteriana/genética , Variación Genética , Genoma Bacteriano/genética , Infecciones por Haemophilus/epidemiología , Infecciones por Haemophilus/mortalidad , Infecciones por Haemophilus/fisiopatología , Haemophilus influenzae/efectos de los fármacos , Haemophilus influenzae/genética , Humanos , Lactante , Recién Nacido , Japón/epidemiología , Pruebas de Sensibilidad Microbiana , Análisis de Secuencia de ADNRESUMEN
The presence of bacteria in the lower airways in COPD results in inflammation, further airway structural damage, and might lead to repeated exacerbations. We have previously shown that chronic colonization of Haemophilus influenzae during stable disease is related to increased inflammation, and we now aimed to relate previous findings of bacterial colonization and inflammation to the degree of radiological findings of bronchiectasis and emphysema. Thirty-nine patients with COPD were included in their stable state, and a high-resolution computed tomography of the lung was performed. They were followed-up monthly for up to a maximum of 6 months or until exacerbation, and they answered questionnaires, performed spirometry, and induced sputum at every visit. Thirty-five patients had emphysema with an emphysema degree of median 20% (interquartile range 10-50), and five patients had bronchiectasis, of which only four could expectorate sputum. The degree of emphysema correlated with several inflammatory mediators in sputum, such as interleukin-8 concentration, myeloperoxidase activity, and Leukotriene B4 concentration. Ten patients were chronically colonized with H. influenzae (ie, had a positive culture for H. influenzae at all visits). The four sputum patients with bronchiectasis were chronically colonized with H. influenzae and showed higher degree of H. influenzae growth compared to patients without bronchiectasis. During exacerbation, there was no longer any correlation between emphysema degree and inflammation, but patients with bronchiectasis showed higher sputum purulence score than patients without bronchiectasis. Emphysema and bronchiectasis in COPD patients show different clinical features. The presence of emphysema is more related to inflammation, while bronchiectasis is associated with bacterial colonization. We believe that both emphysema and bronchiectasis are therefore COPD phenotypes of highest impact and need evaluation to prevent further disease progression.
Asunto(s)
Bronquiectasia/microbiología , Infecciones por Haemophilus/microbiología , Haemophilus influenzae/aislamiento & purificación , Pulmón/microbiología , Neumonía Bacteriana/microbiología , Enfermedad Pulmonar Obstructiva Crónica/microbiología , Enfisema Pulmonar/microbiología , Esputo/microbiología , Tomografía Computarizada por Rayos X , Anciano , Anciano de 80 o más Años , Bronquiectasia/diagnóstico por imagen , Bronquiectasia/fisiopatología , Progresión de la Enfermedad , Femenino , Infecciones por Haemophilus/diagnóstico por imagen , Infecciones por Haemophilus/fisiopatología , Haemophilus influenzae/crecimiento & desarrollo , Humanos , Pulmón/diagnóstico por imagen , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Fenotipo , Neumonía Bacteriana/diagnóstico por imagen , Neumonía Bacteriana/fisiopatología , Valor Predictivo de las Pruebas , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfisema Pulmonar/diagnóstico por imagen , Enfisema Pulmonar/fisiopatología , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores de TiempoRESUMEN
Non-typeable Haemophilus influenzae (NTHi) is the most common pathogen in primary ciliary dyskinesia (PCD) patients. We hypothesised that abnormal ciliary motility and low airway nitric oxide (NO) levels on airway epithelial cells from PCD patients might be permissive for NTHi colonisation and biofilm development.We used a primary epithelial cell co-culture model to investigate NTHi infection. Primary airway epithelial cells from PCD and non-PCD patients were differentiated to ciliation using an air-liquid interface culture and then co-cultured with NTHi.NTHi adherence was greater on PCD epithelial cells compared to non-PCD cells (p<0.05) and the distribution of NTHi on PCD epithelium showed more aggregated NTHi in biofilms (p<0.001). Apart from defective ciliary motility, PCD cells did not significantly differ from non-PCD epithelial cells in the degree of ciliation and epithelial integrity or in cytokine, LL-37 and NO production. Treatment of PCD epithelia using exogenous NO and antibiotic significantly reduced NTHi viability in biofilms compared with antibiotic treatment alone.Impaired ciliary function was the primary defect in PCD airway epithelium underlying susceptibility to NTHi biofilm development compared with non-PCD epithelium. Although NO responses were similar, use of targeted NO with antibiotics enhanced killing of NTHi in biofilms, suggesting a novel therapeutic approach.
Asunto(s)
Células Epiteliales/microbiología , Infecciones por Haemophilus/fisiopatología , Síndrome de Kartagener/microbiología , Óxido Nítrico/farmacología , Adolescente , Adulto , Antibacterianos/farmacología , Adhesión Bacteriana , Proteínas Bacterianas/metabolismo , Biopelículas/crecimiento & desarrollo , Estudios de Casos y Controles , Niño , Preescolar , Citocinas/metabolismo , Femenino , Haemophilus influenzae/patogenicidad , Haemophilus influenzae/fisiología , Humanos , Síndrome de Kartagener/fisiopatología , Masculino , Persona de Mediana Edad , Cultivo Primario de Células , Adulto JovenRESUMEN
Acute otitis media (AOM) is a rapid-onset infection of the middle ear which results in middle ear pressure (MEP), middle ear effusion (MEE), and structural changes in middle ear tissues. Previous studies from our laboratory have identified that MEP, MEE, and middle ear structural changes are three factors affecting tympanic membrane (TM) mobility and hearing levels (Guan et al., 2014, 2013). Sound energy reflectance or absorbance (EA) is a diagnostic tool increasingly used in clinical settings for the identification of middle ear diseases. However, it is unclear whether EA can differentiate these three factors in an AOM ear. Here we report wideband EA measurements in the AOM model of chinchilla at three experimental stages: unopened, pressure released, and effusion removed. These correspond to the combined and individual effects of the three factors on sound energy transmission. AOM was produced by transbullar injection of Haemophilus influenzae in two treatment groups: 4 days (4D) and 8 days (8D) post inoculation. These time points represent the relatively early and later phase of AOM. In each group of chinchillas, EA at 250-8000 Hz was measured using a wideband tympanometer at three experimental stages. Results show that the effects of MEP, MEE, and tissue structural changes over the frequency range varied with the disease time course. MEP was the primary contributor to reduction of EA in 4D AOM ears and had a smaller effect in 8D ears. MEE reduced the EA at 6-8 kHz in 4D ears and 2-8 kHz in 8D ears and was responsible for the EA peak in both 4D and 8D ears. The residual EA loss due to structural changes was observed over the frequency range in 8D ears and only at high frequencies in 4D ears. The EA measurements were also compared with the published TM mobility loss in chinchilla AOM ears.
Asunto(s)
Infecciones por Haemophilus/fisiopatología , Otitis Media con Derrame/fisiopatología , Sonido , Membrana Timpánica/fisiopatología , Absorción Fisicoquímica , Pruebas de Impedancia Acústica , Estimulación Acústica , Enfermedad Aguda , Animales , Chinchilla , Modelos Animales de Enfermedad , Infecciones por Haemophilus/microbiología , Haemophilus influenzae/patogenicidad , Audición , Otitis Media con Derrame/microbiología , Presión , Factores de Tiempo , Membrana Timpánica/microbiologíaRESUMEN
Chronic obstructive pulmonary disease (COPD) is a risk factor for lung cancer. COPD is characterized by chronic airway inflammation and lung infections. The airways of patients with COPD are frequently colonized with bacteria [eg, nontypeable Haemophilus influenzae (NTHi)] that cause pulmonary inflammation and exacerbations. Pulmonary adenocarcinomas are frequently associated with an activating mutation in the KRAS gene. We determined the function of Toll-like receptor (TLR) signaling on the progression of Kras-induced early adenomatous lesions in the lung. Wild-type (WT) mice and mice doubly deficient in Tlr-2 and -4 (Tlr2/4-/-), both with an oncogenic Kras allele in lung epithelium, were exposed to NTHi for 4 weeks. Exposure to NTHi resulted in increased tumor proliferation and growth in WT mice, but not in Tlr2/4-/- mice. Alveolar adenomatous hyperplasia and adenocarcinoma were significantly increased in WT mice compared with Tlr2/4-/- mice. The average size of tumors was significantly larger in WT mice, whereas there was no difference in the number of alveolar lesions between WT and Tlr2/4-/- mice. NTHi-induced pulmonary neutrophilic inflammation and tumor-associated neutrophils were reduced in Tlr2/4-/- mice. Thus, subsequent to a driver mutation, NTHi-induced inflammation promotes proliferation of early adenomatous lesions in a TLR-dependent manner.
Asunto(s)
Genes ras/fisiología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Receptor Toll-Like 2/fisiología , Receptor Toll-Like 4/fisiología , Adenocarcinoma/fisiopatología , Animales , Proliferación Celular/fisiología , Infecciones por Haemophilus/fisiopatología , Haemophilus influenzae/fisiología , Neoplasias Pulmonares/fisiopatología , Ratones , Neutrófilos/fisiología , Enfermedad Pulmonar Obstructiva Crónica/virología , Transducción de Señal/fisiología , Receptor Toll-Like 2/deficiencia , Receptor Toll-Like 4/deficiencia , Proteínas ras/metabolismoRESUMEN
BACKGROUND AND OBJECTIVE: Bronchiectasis is a growing health burden both globally and in Australasia. Associated with repeated respiratory infections, the disease often results in hospital admission, impaired quality of life, reduced lung function and shortened life expectancy. We describe the local clinical, physiological and sputum characteristics in patients hospitalized with an infective exacerbation of bronchiectasis. METHODS: This study examined the medical records of all 61 adults admitted to a metropolitan Australian hospital with an infective exacerbation of bronchiectasis in a calendar year. RESULTS: Baseline characteristics include: mean (SD) age of participants was 66 (14) years; 56% were women and 42% were current or ex-smokers. The majority had other coexisting medical conditions, with asthma in 44%, COPD in 59% and both asthma and COPD in 31%. Seventy-two percent were on regular inhaled medication, 23% on cyclical antibiotics and 26% undertook regular respiratory physiotherapy. Bronchodilator reversibility was present in 17% and small airway reversibility in 41%. Sputum demonstrated normal flora in 17%, Pseudomonas aeruginosa in 32%, Haemophilus influenzae in 15% and both organisms in 17%. Mean numbers of exacerbations per year requiring hospitalization was 2.3. Sixty-two percent of subjects had an Index of Relative Socio-Economic Disadvantage in deciles 1-5. Risk factors for exacerbations included a history of asthma or COPD, documented small airway reversibility and presence of P. aeruginosa. CONCLUSION: Patients hospitalized with an infective exacerbation of bronchiectasis are predominantly older with co-morbidities and of lower socio-economic status. Presence of P. aeruginosa was a risk factor for repeated exacerbations, as was a history of asthma, COPD or small airway reversibility.
Asunto(s)
Asma/epidemiología , Bronquiectasia/epidemiología , Coinfección/epidemiología , Infecciones por Haemophilus/epidemiología , Infecciones por Pseudomonas/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Infecciones del Sistema Respiratorio/epidemiología , Fumar/epidemiología , Administración por Inhalación , Distribución por Edad , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Australasia/epidemiología , Australia/epidemiología , Bronquiectasia/microbiología , Bronquiectasia/fisiopatología , Bronquiectasia/terapia , Coinfección/microbiología , Coinfección/fisiopatología , Comorbilidad , Femenino , Volumen Espiratorio Forzado , Infecciones por Haemophilus/microbiología , Infecciones por Haemophilus/fisiopatología , Haemophilus influenzae , Hospitalización , Humanos , Masculino , Flujo Espiratorio Medio Máximo , Persona de Mediana Edad , Modalidades de Fisioterapia , Infecciones por Pseudomonas/microbiología , Infecciones por Pseudomonas/fisiopatología , Pseudomonas aeruginosa , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/terapia , Calidad de Vida , Terapia Respiratoria , Infecciones del Sistema Respiratorio/microbiología , Infecciones del Sistema Respiratorio/fisiopatología , Factores de Riesgo , Distribución por Sexo , Fumar/fisiopatología , Fumar/terapia , Clase Social , EsputoAsunto(s)
Ampicilina/administración & dosificación , Epiglotitis , Infecciones por Haemophilus , Haemophilus influenzae/aislamiento & purificación , Intubación Intratraqueal/métodos , Administración Intravenosa , Antibacterianos/administración & dosificación , Preescolar , Diagnóstico Diferencial , Manejo de la Enfermedad , Epiglotitis/diagnóstico , Epiglotitis/etiología , Epiglotitis/fisiopatología , Epiglotitis/terapia , Infecciones por Haemophilus/diagnóstico , Infecciones por Haemophilus/tratamiento farmacológico , Infecciones por Haemophilus/fisiopatología , Humanos , Masculino , Cuello/diagnóstico por imagen , Radiografía/métodos , Evaluación de Síntomas/métodos , Resultado del TratamientoRESUMEN
We have established an in vitro 3D system which recapitulates the human tracheo-bronchial mucosa comprehensive of the pseudostratified epithelium and the underlying stromal tissue. In particular, we reported that the mature model, entirely constituted of primary cells of human origin, develops key markers proper of the native tissue such as the mucociliary differentiation of the epithelial sheet and the formation of the basement membrane. The infection of the pseudo-tissue with a strain of NonTypeable Haemophilus influenzae results in bacteria association and crossing of the mucus layer leading to an apparent targeting of the stromal space where they release large amounts of vesicles and form macro-structures. In summary, we propose our in vitro model as a reliable and potentially customizable system to study mid/long term host-pathogen processes.
Asunto(s)
Infecciones por Haemophilus/fisiopatología , Modelos Anatómicos , Mucosa Respiratoria/citología , Infecciones por Haemophilus/metabolismo , Haemophilus influenzae , Humanos , Técnicas In Vitro , Mucosa Respiratoria/virologíaRESUMEN
The MAP-LC3 system regulates the intracellular formation of autophagy-associated vacuoles. These vacuoles contain the LC3 protein; thus it has been utilized as a marker to identify autophagosomes. The aim of our study was to investigate whether Haemophilus influenzae strains and their supernatants could activate autophagy in human larynx carcinoma cell line (HEp-2). We demonstrate that higher expression of the LC3B-II protein was induced, particularly by nontypeable Haemophilus influenzae (NTHi) 49766 and by supernatants, containing <50 kDa proteins, of both strains. Ultrastructural studies demonstrate vacuoles with a double membrane and/or membrane material inside, showing similar features to those of autophagic vacuoles. Together, our findings demonstrate that H. influenzae strains and their supernatants trigger an autophagic process.
Asunto(s)
Autofagia/fisiología , Infecciones por Haemophilus/fisiopatología , Haemophilus influenzae/fisiología , Línea Celular Tumoral , Humanos , Proteínas Asociadas a Microtúbulos/genética , Regulación hacia Arriba , Vacuolas/ultraestructuraRESUMEN
Acute otitis media, inflammation of the middle ear, is the most common bacterial infection in children and, as a consequence, is the most common reason for antimicrobial prescription to this age group. There is currently no effective vaccine for the principal pathogen involved, non-typeable Haemophilus influenzae (NTHi). The most frequently used and widely accepted experimental animal model of middle ear infection is in chinchillas, but mice and gerbils have also been used. We have established a robust model of middle ear infection by NTHi in the Junbo mouse, a mutant mouse line that spontaneously develops chronic middle ear inflammation in specific pathogen-free conditions. The heterozygote Junbo mouse (Jbo/+) bears a mutation in a gene (Evi1, also known as Mecom) that plays a role in host innate immune regulation; pre-existing middle ear inflammation promotes NTHi middle ear infection. A single intranasal inoculation with NTHi produces high rates (up to 90%) of middle ear infection and bacterial titres (10(4)-10(5) colony-forming units/µl) in bulla fluids. Bacteria are cleared from the majority of middle ears between day 21 and 35 post-inoculation but remain in approximately 20% of middle ears at least up to day 56 post-infection. The expression of Toll-like receptor-dependent response cytokine genes is elevated in the middle ear of the Jbo/+ mouse following NTHi infection. The translational potential of the Junbo model for studying antimicrobial intervention regimens was shown using a 3 day course of azithromycin to clear NTHi infection, and its potential use in vaccine development studies was shown by demonstrating protection in mice immunized with killed homologous, but not heterologous, NTHi bacteria.
Asunto(s)
Infecciones por Haemophilus/microbiología , Infecciones por Haemophilus/fisiopatología , Haemophilus influenzae , Otitis Media/microbiología , Otitis Media/fisiopatología , Animales , Azitromicina/química , Modelos Animales de Enfermedad , Infecciones por Haemophilus/genética , Heterocigoto , Inmunidad Innata , Inflamación , Ratones , Ratones Endogámicos C3H , Ratones Mutantes , Microesferas , Mutación , Otitis Media/genética , Transducción de Señal , Células MadreRESUMEN
BACKGROUND: Inhaled corticosteroids (ICS) are widely used in the treatment of obstructive lung diseases. Recent data suggest a higher pneumonia risk in chronic obstructive pulmonary disease (COPD) patients treated with ICS. OBJECTIVE: Since non-typeable Haemophilus influenzae (NTHi) is the most common pathogen associated with acute exacerbations of COPD, we investigated the effects of budesonide (BUD) on NTHi-induced inflammation and invasive infection. METHODS: The alveolar epithelial cell line A549 and specimens of human lung tissue (HLT) were used in our experiments. Intracellular infection was determined by a lysis/culture assay of infected cells. Activated p38 mitogen-associated protein kinase (MAPK) was assessed using Western blotting and immunohistochemistry, expression of toll-like receptor 2 (TLR2) was determined by PCR, and CXCL-8 levels were measured using ELISA. Immunohistochemistry was used for detection of CXCL-8, platelet-activating factor receptor (PAF-R) and NTHi. RESULTS: BUD significantly reduced CXCL-8 secretion in A549 cells and lung tissue infected with NTHi. Furthermore, BUD decreased the expression of PAF-R in HLT and A549 cells. In A549 cells and HLT, BUD inhibited intracellular infection and - synergistically with NTHi - increased the expression of TLR2 (in A549 cells). TLR2 stimulation did not influence the intracellular infection of A549 cells, but p38 MAPK inhibition resulted in a significant reduction of infection. CONCLUSION: The present study adds new insights into the effects of glucocorticoids on pulmonary host defence after NTHi infection. Although the inflammatory response to infection is suppressed by BUD, interestingly, the intracellular infection is also inhibited. This effect seems to depend on the inhibition of p38 MAPK - a key enzyme in many pro-inflammatory pathways - as well as of PAF-R expression.
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Budesonida/farmacología , Haemophilus influenzae/efectos de los fármacos , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Administración por Inhalación , Antiinflamatorios/farmacología , Western Blotting , Budesonida/efectos adversos , Células Cultivadas , Medios de Cultivo Condicionados , Inducción Enzimática/efectos de los fármacos , Ensayo de Inmunoadsorción Enzimática , Células Epiteliales/efectos de los fármacos , Infecciones por Haemophilus/etiología , Infecciones por Haemophilus/fisiopatología , Humanos , Inmunohistoquímica , Reacción en Cadena de la Polimerasa , Enfermedad Pulmonar Obstructiva Crónica/microbiología , Sensibilidad y Especificidad , Proteínas Quinasas p38 Activadas por Mitógenos/efectos de los fármacosRESUMEN
Measures of ventilation distribution are promising for monitoring early lung disease in cystic fibrosis (CF). This study describes the cross-sectional and longitudinal impacts of pulmonary inflammation and infection on ventilation homogeneity in infants with CF.Infants diagnosed with CF underwent multiple breath washout (MBW) testing and bronchoalveolar lavage at three time points during the first 2â years of life.Measures were obtained for 108 infants on 156 occasions. Infants with a significant pulmonary infection at the time of MBW showed increases in lung clearance index (LCI) of 0.400 units (95% CI 0.150-0.648; p=0.002). The impact was long lasting, with previous pulmonary infection leading to increased ventilation inhomogeneity over time compared to those who remained free of infection (p<0.05). Infection with Haemophilus influenzae was particularly detrimental to the longitudinal lung function in young children with CF where LCI was increased by 1.069 units for each year of life (95% CI 0.484-1.612; p<0.001).Pulmonary infection during the first year of life is detrimental to later lung function. Therefore, strategies aimed at prevention, surveillance and eradication of pulmonary pathogens are paramount to preserve lung function in infants with CF.
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Fibrosis Quística/fisiopatología , Infecciones por Haemophilus/fisiopatología , Neumonía Bacteriana/fisiopatología , Infecciones por Pseudomonas/fisiopatología , Aspergilosis Pulmonar/fisiopatología , Infecciones Estafilocócicas/fisiopatología , Pruebas Respiratorias , Lavado Broncoalveolar , Líquido del Lavado Bronquioalveolar/inmunología , Preescolar , Estudios Transversales , Fibrosis Quística/inmunología , Progresión de la Enfermedad , Femenino , Infecciones por Haemophilus/inmunología , Haemophilus influenzae , Humanos , Lactante , Recién Nacido , Interleucina-8/inmunología , Estudios Longitudinales , Masculino , Neumonía Bacteriana/inmunología , Infecciones por Pseudomonas/inmunología , Pseudomonas aeruginosa , Aspergilosis Pulmonar/inmunología , Ventilación Pulmonar , Infecciones Estafilocócicas/inmunología , Staphylococcus aureusRESUMEN
BACKGROUND: Some patients with chronic obstructive pulmonary disease (COPD) show increased airway inflammation and bacterial colonization during stable phase. The aim of this study was to follow COPD patients and investigate chronic colonization with pathogenic bacteria during stable disease phase, and relate these findings to clinical parameters, inflammatory pattern, lung function, and exacerbations. METHODS: Forty-three patients with COPD were included while in a stable state and followed up monthly until exacerbation or for a maximum of 6 months. The patients completed the Clinical COPD Questionnaire and Medical Research Council dyspnea scale questionnaires, and exhaled breath condensate was collected, followed by spirometry, impulse oscillometry, and sputum induction. RESULTS: Ten patients were chronically colonized (ie, colonized at all visits) with Haemophilus influenzae during stable phase. These patients had higher sputum levels of leukotriene B4 (P<0.001), 8-isoprostane (P=0.002), myeloperoxidase activity (P=0.028), and interleukin-8 (P=0.02) during stable phase when compared with other patients. In addition, they had lower forced vital capacity (P=0.035) and reactance at 5 Hz (P=0.034), but there was no difference in forced expiratory volume in 1 second (FEV1), FEV1 % predicted, forced vital capacity % predicted, exhaled breath condensate biomarkers, C-reactive protein, or Clinical COPD Questionnaire and Medical Research Council dyspnea scale results. Three patients had intermittent colonization (colonized at only some visits) of H. influenzae during stable phase, and had lower levels of inflammatory biomarkers in sputum when compared with the chronically colonized patients. The difference in airway inflammation seen during stable phase in patients chronically colonized with H. influenzae was not observed during exacerbations. CONCLUSION: Some COPD patients who were chronically colonized with H. influenzae during stable phase showed increased airway inflammation and reduced lung volumes when compared with non-chronically colonized patients.
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Infecciones por Haemophilus/microbiología , Haemophilus influenzae/aislamiento & purificación , Pulmón/microbiología , Neumonía Bacteriana/microbiología , Enfermedad Pulmonar Obstructiva Crónica/microbiología , Anciano , Pruebas Respiratorias , Progresión de la Enfermedad , Disnea/epidemiología , Femenino , Volumen Espiratorio Forzado , Infecciones por Haemophilus/diagnóstico , Infecciones por Haemophilus/inmunología , Infecciones por Haemophilus/fisiopatología , Haemophilus influenzae/inmunología , Humanos , Mediadores de Inflamación/inmunología , Estimación de Kaplan-Meier , Pulmón/inmunología , Pulmón/fisiopatología , Mediciones del Volumen Pulmonar , Masculino , Persona de Mediana Edad , Neumonía Bacteriana/diagnóstico , Neumonía Bacteriana/inmunología , Neumonía Bacteriana/fisiopatología , Valor Predictivo de las Pruebas , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/inmunología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Espirometría , Esputo/inmunología , Esputo/microbiología , Encuestas y Cuestionarios , Factores de Tiempo , Capacidad VitalRESUMEN
Due to the introduction of the conjugate vaccine against serotype b, neonatal sepsis caused by Haemophilus influenzae became very rare. There is little data in Belgium concerning the prevalence of H. influenzae early onset neonatal sepsis and articles about neonatal sepsis and H. influenzae published in the last decade are scarce. We report two invasive infections with a non-typeable H. influenzae. These cases show that neonatal sepsis caused by non-typeable H. influenzae may be underestimated and we believe that there is need for a better registration of this kind of infection.
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Cefotaxima/administración & dosificación , Infecciones por Haemophilus , Haemophilus influenzae , Sepsis , Tobramicina/administración & dosificación , Antibacterianos/administración & dosificación , Femenino , Infecciones por Haemophilus/tratamiento farmacológico , Infecciones por Haemophilus/microbiología , Infecciones por Haemophilus/fisiopatología , Haemophilus influenzae/efectos de los fármacos , Haemophilus influenzae/inmunología , Humanos , Recién Nacido , Pruebas de Sensibilidad Microbiana , Sepsis/tratamiento farmacológico , Sepsis/microbiología , Sepsis/fisiopatología , Serotipificación/métodos , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND AND OBJECTIVE: Nontuberculous mycobacterial (NTM) lung disease secondary to cystic fibrosis (CF) has been reported, but there is limited data about NTM prevalence in non-CF bronchiectasis. We retrospectively investigated the prevalence of NTM associated with diffuse panbronchiolitis (DPB), a disorder also characterized by reduced mucociliary clearance with bronchiectasis. METHODS: We reviewed mycobacterial cultures, patient characteristics and computed tomography findings of 33 patients with DPB between January 2000 and December 2012. Prevalence was based on at least one positive NTM culture. RESULTS: Mean patient age was 51.5 years. During a mean 162.8-month follow-up, the prevalence of NTM in sputum was 21.2% (seven patients). Of the seven positive patients, six had Mycobacterium avium complex, one had M. kansasii and M. chelonae co-cultured with M. avium complex. Three patients were positive twice, and two had positive smears. The mean time from DPB diagnosis to the first positive result was 194.6 months. NTM-positive patients tended to have lower forced expiratory volume in 1 s (% predicted) than NTM-negative patients (50.0% vs 77.3%, P = 0.03), but there were no radiological or clinical differences between the two groups. CONCLUSIONS: Our observations suggest that NTM is found more often in DPB. Defects of mucociliary clearance may predispose individuals to NTM infection.
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Bronquiectasia/epidemiología , Bronquiolitis/epidemiología , Infecciones por Haemophilus/epidemiología , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Micobacterias no Tuberculosas , Adolescente , Adulto , Anciano de 80 o más Años , Bronquiectasia/diagnóstico por imagen , Bronquiectasia/microbiología , Bronquiolitis/diagnóstico por imagen , Bronquiolitis/microbiología , Bronquiolitis/fisiopatología , Fibrosis Quística/microbiología , Femenino , Volumen Espiratorio Forzado , Infecciones por Haemophilus/diagnóstico por imagen , Infecciones por Haemophilus/microbiología , Infecciones por Haemophilus/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Depuración Mucociliar , Infecciones por Mycobacterium no Tuberculosas/diagnóstico por imagen , Infecciones por Mycobacterium no Tuberculosas/fisiopatología , Prevalencia , Estudios Retrospectivos , Esputo/microbiología , Tomografía Computarizada por Rayos XRESUMEN
Bacterial infection of the lower respiratory tract in chronic obstructive pulmonary disease (COPD) patients is common both in stable patients and during acute exacerbations. The most frequent bacteria detected in COPD patients is Haemophilus influenzae, and it appears this organism is uniquely adapted to exploit immune deficiencies associated with COPD and to establish persistent infection in the lower respiratory tract. The presence of bacteria in the lower respiratory tract in stable COPD is termed colonization; however, there is increasing evidence that this is not an innocuous phenomenon but is associated with airway inflammation, increased symptoms, and increased risk for exacerbations. In this review, we discuss host immunity that offers protection against H. influenzae and how disturbance of these mechanisms, combined with pathogen mechanisms of immune evasion, promote persistence of H. influenzae in the lower airways in COPD. In addition, we examine the role of H. influenzae in COPD exacerbations, as well as interactions between H. influenzae and respiratory virus infections, and review the role of treatments and their effect on COPD outcomes. This review focuses predominantly on data derived from human studies but will refer to animal studies where they contribute to understanding the disease in humans.