Distribution of emphysema and fibrosis in idiopathic pulmonary fibrosis with coexisting emphysema.

In the autopsied and pneumonectomised specimens of IPF patients with emphysema, craniocaudal separation of emphysema and fibrosis (emphysema in the upper lobes and interstitial pneumonia in the lower lobes) was histologically rare; coexistence or collision of fibrosis and emphysema in each lobe was common.