Recent advances in diagnosis and management of chronic bronchitis and emphysema

Bronchitis

Bronchitis is characterized by bronchial inflammation that results in …

Virus infection in exacerbations of chronic obstructive pulmonary disease requiring ventilation

Objectives

We aimed to characterise and quantify the incidence of common infectious agents in acute exacerbations of chronic obstructive pulmonary disease (COPD) requiring ventilation, with a focus on respiratory viruses.

Design

An epidemiological study conducted over 3 years.

Setting

A 12-bed intensive care unit (ICU).

Participants

ICU patients over 45 years of age with a primary diagnosis of COPD exacerbation requiring non-invasive ventilation (NIV) or ventilation via endotracheal tube (ETT).

Materials and methods

Nasopharyngeal aspirates (NPA) and posterior pharyngeal swabs (PS) were tested for viruses with immunofluorescence assay (IFA), virus culture (VC) and polymerase chain reaction (PCR). Paired virus and atypical pneumonia serology assays were taken. Blood, sputum and endotracheal aspirates were cultured for bacteria.

Results

107 episodes in 105 patients were recorded. Twenty-three (21%) died within 28 days. A probable infectious aetiology was found in 69 patient episodes (64%). A virus was identified in 46 cases (43%), being the sole organism in 35 cases (33%) and part of a mixed infection in 11 cases (10%). A probable bacterial aetiology was found in 25 cases (23%). There was no statistically significant difference in clinical characteristics or outcomes between the group with virus infections and that without.

Conclusion

Forty-six (43%) of the patients with COPD exacerbation requiring mechanical ventilation had a probable viral pathogen. Prodromal, clinical and outcome parameters did not distinguish virus from non-virus illness. PCR was the most sensitive whilst virus culture was the least of virus assays.

Electronic supplementary material

The electronic reference of this article is http://dx.doi.org/10.1007/s00134-006-0202-x. The online full-text version of this article includes electronic supplementary material. This material is available to authorised users and can be accessed by means of the ESM button beneath the abstract or in the structured full-text article. To cite or link to this article you can use the above reference.

Evaluation of excised lung gas volume measurements in animals with genetic or induced emphysema

Emphysema, a leading cause of respiratory disability and mortality in humans, is characterized by destruction of alveolar walls and enlargement of airspaces. Animal studies are critical in understanding the pathogenesis of emphysema. However, current measurements of airspace enlargement and emphysema in small laboratory animals are labor intensive and may not be sensitive enough for measuring alterations in lung function and structure at the early stages of emphysema. In this study, we have investigated the excised lung gas volume (ELGV) measurement as a potential index for determining airspace enlargement in pallid mice with developing emphysema, in tight-skin mice with developed emphysema, or in Wistar rats with emphysema induced by an intratracheal instillation of pancreatic elastase. Our results showed that values of both ELGV per lung and per gram lung tissue were significantly increased in all three emphysema models, compared to control. The ELGV values were correlated well with morphometric evaluation of emphysema. Variations in transpulmonary pressures caused by different termination procedures were critical factors influencing the ELGV values. The present study demonstrates that ELGV measurement is a simple and sensitive method to monitor the development of emphysema.

Validation of a Chronic Obstructive Pulmonary Disease screening questionnaire for population surveys

The Confronting Chronic Obstructive Pulmonary Disease (COPD) Survey in North America and Europe conducted during 1999-2000 aimed to identify international differences in the clinical management of COPD and the patients' perspectives on their disease. Our aim was to validate the screening questionnaire used in this study in a sample of patients presenting at a respiratory clinic. Interviews were conducted at an outpatient clinic of the London Chest Hospital. Of the 136 patients contacted, 25 refused or were not able to participate. Questionnaire data were validated by comparison with medical records and spirometry on 104 patients. Overall, the questionnaire correctly identified 86.5% of patients with a diagnosis of COPD with a chance-corrected agreement (kappa = 0.66, SE 0.098), which indicates good agreement between the questionnaire alpha and the medical records. The questionnaire had a high sensitivity (92.0%) and specificity (72.4%) with respect to the diagnosis of COPD. The screening questionnaire used in The Confronting COPD Survey appears to be a valid screening tool to differentiate COPD from other respiratory diseases.

Can Exogenously Administered Hyaluronan Improve Respiratory Function in Patients With Pulmonary Emphysema?

While most attempts at developing a treatment for pulmonary emphysema have focused on the use of elastase inhibitors to reduce elastic fiber damage and the loss of alveoli, this laboratory has developed a method of preventing such injury by the intratracheal administration of hyaluronan (HA). Animals treated with HA prior to the induction of experimental emphysema develop significantly less disease than untreated controls. The protective effect of HA may be related to its ability to bind to lung elastic fibers, thereby preventing their breakdown by elastases. Although clinical trials involving nebulized HA are not expected to yield a measurable treatment effect for at least several years, it is proposed that the special ability of this polysaccharide to retain water may increase the elasticity of lung elastic fibers, producing a relatively rapid improvement in pulmonary mechanics. Such an outcome might speed the development of this potential treatment for pulmonary emphysema.

Advances in the management of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a progressive and irreversible airflow limitation with extreme economic and social burden. It is estimated that over the next two decades, it will become the 5(th) most prevalent disease and the 3(rd) most common cause of death in the world. A better understanding of the pathogenesis of airway inflammation and alveolar destruction allows for the development of new therapeutic targets. Tobacco smoking is the most important risk factor in the development of COPD, thus making smoking cessation of the outermost importance. This article provides a critical review of present therapy for COPD. In addition to conventional treatment (bronchodilators, corticosteroids and antibiotics) and smoking cessation therapies, novel approaches with potential benefit are discussed.