This study demonstrates that chronic cough without asthma or known cause is associated with lower airway inflammation. The inflammatory response was noneosino-philic in all patients and neutrophilic in the majority, and this was accompanied by increased microvascular leakage (as measured by fibrinogen and albumin levels), high levels of IL-8 and substance P, and low levels of ECP. Treatment with inhaled budesonide 800 |ig daily for two or four weeks did not improve cough discomfort or sputum inflammatory indices, possibly because the cause was not associated with sputum eosinophilia. buy prednisone
There are still only a few investigations of airway inflammation in chronic cough in nonasthmatic patients or of its relevance to the effects of treatment. The studies differ in methods and subject selection. The emerging data are, not surprisingly, contradictory. Gibson et al selected patients with eosinophilia, and observed that treatment with an inhaled steroid reversed the cough and eosinophilia. The eosi-nophilia was associated with IL-5 and granulocyte-macrophage colony-stimulating factor mRNA expression in bronchoalveolar lavage cells . This condition, termed eosinophilic bronchitis without asthma , occurred in 10% of 30 consecutive adults with chronic cough referred to a tertiary care clinic . In contrast, Boulet et al performed bronchial biopsies in patients with chronic cough associated with gastroesophageal reflux, postnasal drip or with no identifiable cause.