Sodium cromoglycate attenuates pulmonary inflammation without influencing bronchial responsiveness in healthy subjects exposed to organic dust

Background Inhalation of organic dust from a pig house induces airway infla mmation and increases bronchial responsiveness to methacholine in healthy s ubjects. Objective To study whether sodium cromoglycate influences the airway inflam matory reaction and the increase in airway responsiveness induced by inhala tion of organic dust. Methods Bronchoalveolar and nasal lavages, and bronchial methacholine chall anges were performed and blood samples were drawn in 32 healthy subjects be fore and after exposure to dust in a pig farm. Sodium cromoglycate was inha led (20 mg, twice a day) and administered intranasally (5.2 mg, twice a day ) by 16 and a corresponding placebo was given to the other 16 healthy contr ols for two weeks prior to exposure. Results Exposure induced a significant increase in inflammatory cells and s oluble components (pro-inflammatory cytokines, inflammatory mediators) in b ronchoalveolar and nasal lavage fluid in both groups. The increase in neutr ophils, interleukin (IL)-6 and tumour necrosis factor (TNF)-alpha as well a s myeloperoxidase and soluble intracellular adhesion molecule (ICAM)-1 in b ronchoalveolar lavage (BAL) fluid was significantly reduced by treatment wi th sodium cromoglycate. Although sodium cromoglycate inhalation largely inf luenced a variety of inflammatory indices in bronchoalveolar lavage fluid i t had no effect on the increase in bronchial responsiveness to methacholine . Conclusion Sodium cromoglycate alters the airway inflammatory response to i nhaled organic dust without influencing the dust-induced increase in bronch ial responsiveness to methacholine.