Effect of beclomethasone dipropionate inhalation on eosinophilic bronchitis in patients with silicosis

The efficacy of beclomethasone dipropionate (CAS 5534-09-8, BDP, beclomethasone) inhalation therapy over the course of 12 months were evaluated in 42 patients with established chronic silicosis. Their pulmonary functions were monitored every 3 months and volume of sputum production was established daily. Subjects were divided randomly into two groups; 21 patients (BDP group) were treated with BDP (400 micrograms/day) by way of a metered-dose inhaler, while the 21 controls did not receive the BDP inhalation therapy. Although FVC (forced vital capacity), FEV1 (forced expiratory volume in 1 s), MMEF (maximal mean expiratory flow) and arterial blood oxygen tension did not improve significantly, sputum production significantly decreased in the BDP group. The patients who responded most dramatically to the treatment presented with sputum eosinophilia and elevated serum IgE levels prior to therapy. Pulmonary tuberculosis or exacerbation of chronic airway infection was not observed in any of the patients. These results suggest that corticosteroid inhalation therapy is helpful in the management of chronic silicosis, especially in patients with sputum eosinophilia. Positive atopic factors may be related to the pathogenesis of eosinophilic bronchitis, a complication of chronic silicosis.