title: [Chronic obstructive pulmonary disease and bronchial colonization/infection].
abstract: BACTERIAL FLORA IN THE SUBGLOTTAL AIRWAYS: In healthy non-smoking subjects, the subglottal airways are sterile. Inversely, bacteria are often isolated from the sublottal airways in patients with obstructive or non-obstructive chronic bronchitis, both during and between acute exacerbations. The significance of this bacterial colonization/infection, its natural history, and its impact on the course of chronic lung disease is poorly understood. BETWEEN EXACERBATIONS: 30 to 40% of all patients with chronic obstructive pulmonary disease in a stable situation without recent antibiotic therapy harbor potential pathogens in their intra-thoracic airways. The prevalence of Gram-negative bacilli increases in the more severe forms. This estimation is possibly biased due to the involuntary inclusion of patients with bronchial dilatation, since bronchectasia involves a high prevalence of bronchial colonization/infection. DURING EXACERBATIONS: The prevalence of bronchial colonization/infection by potential pathogens is to the order of 30-50%, irrespective of the bacteria isolated from endobronchial samples made during or between exacerbations. About half of the exacerbations would not be related to bacterial infection, but to viral infection. The other identified causes of exacerbations are: occupational or accidental exposure, co-morbidity (chronic sinus infection, chronic pharyngeal discharge, left ventricular failure, non-specific bronchial hyperreactivity). INFLAMMATION: Inflammation of the bronchial mucosa is a constant feature of chronic obstructive pulmonary disease. The biological and histocytological features are distinctive from those observed in asthma. Polynuclear activation appears to play an important role in polynuclear infiltration of the mucosa,  amplified during bacterial colonization.
authors.affiliation: Service de pneumologie et réanimation respiratoire, Hôpital Beaujon, Clichy.
authors.forename: M
authors.initials: M
authors.lastname: Fournier
mesh_terms: D000368:Aged; D001419:Bacteria / Q000302:isolation & purification*; D001424:Bacterial Infections / Q000150:complications* / Q000175:diagnosis; D001980:Bronchi / Q000382:microbiology* / Q000473:pathology; D002986:Clinical Trials as Topic; D006193:Haemophilus influenzae / Q000302:isolation & purification; D006801:Humans; D007249:Inflammation / Q000473:pathology; D001936:Moraxella catarrhalis / Q000302:isolation & purification; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification; D029424:Pulmonary Disease, Chronic Obstructive / Q000209:etiology / Q000382:microbiology*; D020545:Respiratory Mucosa / Q000382:microbiology / Q000473:pathology; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D013211:Staphylococcus aureus / Q000302:isolation & purification; D013296:Streptococcus pneumoniae / Q000302:isolation & purification; D013997:Time Factors; D014777:Virus Diseases / Q000150:complications