Regional distribution of macroscopic lung disease in cystic fibrosis

Abstract

We used macroscopic morphometry and multivariate analysis (Hotelling's T2) to quantitate the extent of chronic lung disease and its regional distribution in formalin-inflated right lungs obtained at autopsy from 17 young adults with cystic fibrosis (CF) and 5 without CF as control subjects. Lungs were point-counted, by lobe, for 6 anatomic variables: parenchyma, nonparenchyma, bronchi, vessels, cysts, and emphysema, and the results were expressed for each as volume proportion (Vv). Considering all 6 variables simultaneously, CF lungs differed significantly from control lungs (p = 0.003). For individual variables, Vv bronchus was significantly elevated and Vv parenchyma was significantly reduced in the CF group. Within the CF lungs, there was a significant difference between upper and lower lobes when all variables were considered together (p = 0.001). For individual variables, Vv parenchyma and Vv vessels were significantly less, and Vv bronchus was significantly greater in the upper compared with the lower lobe. There was no difference in the upper versus lower lobe Vv for any variable in the control group. These results indicate that lung disease and remodeling are irregularly distributed in CF and that the upper lobe is disproportionately severely involved.