[CEA and CA19-9 in BALF from patients with idiopathic interstitial pneumonia]

Carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) were measured in bronchoalveolar lavage fluid (BALF) in 21 patients with idiopathic interstitial pneumonia (IIP) and 7 healthy volunteers. The concentrations of both CEA and CA19-9 in the BALF were significantly higher in patients with IIP than those in healthy subjects. Significant correlations were present between the concentration of CEA and neutrophil percentage of the total BALF cells and between the concentration of CA19-9 and neutrophil percentage of the total BALF cells in the patients with IIP. Immunohistochemical study of tissue CEA and CA19-9 in the postmortem lungs of patients with IIP showed that CEA staining was present in the epithelia of respiratory bronchioles and alveoli, and it was especially increased in the region of alveoli where type II pneumocytes proliferate. CA19-9 staining was present in the epithelia of the respiratory bronchioles but absent in the epithelia of alveoli. It seems that assay of CEA in BALF may be useful to estimate the degree of pathological change and the activity of IIP.