Role of bronchoalveolar lavage in the initial diagnosis of smoking-related interstitial lung diseases.

Some of interstitial lung diseases have a potential relation to tobacco smoking and are known as smoking-related interstitial lung diseases (sr-ILD). The aim of this study was to present the typical features in bronchoalveolar lavage fluid (BALF) of patients with sr-ILD with special account to the morphology of alveolar macrophages. We have found typical features of sr-LD in 18 patients with interstitial lung disease. All patients were smokers. Pulmonary function was moderately impaired. Control group consisted of 12 asymptomatic smokers and 18 healthy nonsmokers. The median total cell count in BALF of patients with desquamative interstitial pneumonia was 64.5 x 10(6) and was much higher than in asymptomatic smokers--9.0 x 10(6), and healthy nonsmokers--3.25 x 10(6). A high proportion (mean 90%) and number (55.5 x 10(6)) of macrophages with the predominance of pigmented cells was found. Mean proportion of CD14 positive macrophages was 6%, and of CD54 positive macrophages - 62%. We concluded that features in BALF typical for sr-ILD are uncommon among routinely evaluated specimens, but differ markedly from other forms of ILD.