Relationship between Lung Inflammation or Fibrosis and Frequency Dependence of Compliance in Interstitial Pulmonary Diseases

Abstract

In order to find a physiological parameter which discriminates between the predominance of inflammation or fibrosis, pulmonary function tests and open lung biopsy were performed on 19 patients with interstitial lung disease. Our results showed that the only test which may be useful is the dynamic lung compliance/quasi-static lung compliance (C_dyn/C_st) index. In this context, values equal or lower than 0.85 of the C_dyn/C_st index indicate that inflammation predominates, and values higher than 0.85 suggest that interstitial fibrosis is the main feature

Hypersensitivity Pneumonitis Reaction to Mycobacterium avium in Household Water

“…31 Finally, the finding of airflow limitation in our case and in those previously reported differs from classic hypersensitivity pneumonitis, where restriction is the dominant spirometric abnormality. The finding of airflow limitation is likely secondary to a bronchiolitis, which has been shown to correlate with obstruction in hypersensitivity pneumonitis, 32 and likely dominates the determinants of physiologic manifestations of MAC hypersensitivity pneumonitis.…”