[Cytological examination of bronchoalveolar lavage fluid and its clinical significance in patients with diffuse interstitial lung diseases].

Cytological examination of bronchoalveolar lavage fluid (BALF) was carried out in 48 patients with diffuse interstitial lung diseases based on chest roentgenography. 7 cases manifested with respiratory symptoms but without any abnormality on both chest roentgenogram and fibroptic bronchoscopy served as controls. The total cell counts of BALF in the study group were all higher than those of the control group (3.1 x 10(5)/ml) and the differential count of the cells showed that neutrophilic granulocytes was found in patients with fibrosing alveolitis, Neutrophilic granulocytes accounted for 21.3 +/- 2.4% of all the cells and the percentage was significantly higher than that of the control group (1.8 +/- 0.5% P less than 0.01). On the contrary, lymphocytosis was found in patients with allergic alveolitis and sarcoidosis; lymphocytes accounted for 30.8 +/- 5.3% and 29.0 +/- 1.1% of all the cells in these two diseases respectively and the percentage was also higher than that of the control group (3.0 +/- 0.6% P less than 0.01). However, the differential cell count of BALF in alveolar carcinoma showed no significant difference with that of the control group (P greater than 0.05). The factors influencing the quality control of both BAL and cytological examination were evaluated and the clinical significance of these results was discussed.