[Comparison of acute bronchodilator response between cases of diffuse panbronchiolitis and pulmonary emphysema]

Diffuse panbronchiolitis (DPB) is a disease characterized clinically by chronic airflow limitation, therefore patients with DPB are frequently treated with bronchodilators. However, there have been no reports on bronchodilator effects in patients with DPB. Because bronchodilator effects can be influenced by low baseline level of pulmonary function, we evaluated acute responses to inhaled metaproterenol (10 mg) in 31 patients with DPB and in 40 patients with pulmonary emphysema. Patients of both groups were clinically diagnosed, and, in addition, by usage of high-resolution computed tomography. All the subjects in both groups had a post-bronchodilator FEV1/FVC less than 0.7. There was no difference in baseline FEV1 between either group; FEV1 was 1.24 +/- 0.64 l (47.1 +/- 17.8% pred) in DPB vs. 1.24 +/- 0.64 l (51.0 +/- 19.0% pred) in pulmonary emphysema. Two indices, post FEV1/pre FEV1 and post FEV1-pre FEV1/predicted FEV1, were used for the judgement of bronchodilator response. Post FEV1/pre FEV1 was 110.3 +/- 9.3% in DPB and 119.9 +/- 17.1% in pulmonary emphysema. Post FEV1-pre FEV1/predicted FEV1 was 4.5 +/- 4.2% in DPB and 8.6 +/- 6.2% in pulmonary emphysema. Bronchodilator responses for both indices was larger in pulmonary emphysema than in DPB (both, p less than 0.01). It has been reported that post FEV1/pre FEV1 correlates negatively to baseline FEV1 and that post FEV1-pre FEV1/predicted FEV1 is positively correlated to baseline FEV1.(ABSTRACT TRUNCATED AT 250 WORDS)