Bronchial inflammation in seasonal allergic rhinitis with or without asthma in relation to natural exposure to pollen allergens.

BACKGROUND: Nasal inflammation in allergic rhinitis enhances bronchial Th2 driven inflammation and development of asthma. We assessed bronchial inflammation induced by natural allergen exposure during pollen season in patients with pollinosis with or without asthma to show the intensity of inflammation in asthma and rhinitis and possible persistence of inflammation in periods without allergen exposure. METHODS: Sputum was induced in 52 patients with seasonal allergic rhinitis without asthma, 38 patients with seasonal allergic rhinitis and seasonal asthma and 23 healthy volunteers. Sampling was performed 6-8 weeks before the expected beginning of symptoms, during symptomatic period and 6-8 weeks after the end of symptoms. Sputum ECP was measured by means of chemi-luminiscent immunometric assay and sputum cell counts were assessed by classical staining and immunocytochemistry. RESULTS: Sputum eosinophils were on the whole higher in both asthma and rhinitis compared to controls (p<0.001, p=0.003). The rise of eosinophils during pollen season compared with values out of pollen season was significant in asthma (classical staining) (p=0.014) and slightly apparent in rhinitis (immunocytochemistry) (p=0.073). The seasonal rise of sputum ECP was observed only in rhinitis (p=0.006). CONCLUSIONS: Inflammation of the lower airway in patients with allergic rhinitis with and without asthma has been confirmed by means of both sputum eosinophil count and sputum ECP level. Persistent inflammation of lower airway in periods without allergen exposure was proven in seasonal asthma. This may have implications for the therapy of seasonal allergic rhinitis with and without asthma in terms of promoting long-term anti-inflammatory treatment.

Viruses and bacteria in acute asthma exacerbations--a GA² LEN-DARE systematic review.

A major part of the burden of asthma is caused by acute exacerbations. Exacerbations have been strongly and consistently associated with respiratory infections. Respiratory viruses and bacteria are therefore possible treatment targets. To have a reasonable estimate of the burden of disease induced by such infectious agents on asthmatic patients, it is necessary to understand their nature and be able to identify them in clinical samples by employing accurate and sensitive methodologies. This systematic review summarizes current knowledge and developments in infection epidemiology of acute asthma in children and adults, describing the known impact for each individual agent and highlighting knowledge gaps. Among infectious agents, human rhinoviruses are the most prevalent in regard to asthma exacerbations. The newly identified type-C rhinoviruses may prove to be particularly relevant. Respiratory syncytial virus and metapneumovirus are important in infants, while influenza viruses seem to induce severe exacerbations mostly in adults. Other agents are relatively less or not clearly associated. Mycoplasma and Chlamydophila pneumoniae seem to be involved more with asthma persistence rather than with disease exacerbations. Recent data suggest that common bacteria may also be involved, but this should be confirmed. Although current information is considerable, improvements in detection methodologies, as well as the wide variation in respect to location, time and populations, underline the need for additional studies that should also take into account interacting factors.