Bronchoalveolar lavage findings in patients with diffuse interstitial lung disease (DILDs)

Abstract

<b>BACKGROUND:</b> Bronchoalveolar lavage (BAL) analysis has been used for differential diagnosis of DILDs,but their clinical usefulness is controversial.The objective of this study was to perform a descriptive analysis of the cytologic and of the lymphocyte subpopulations in BAL from patients with ILD. <b>METHODS:</b> 62 patients with DILDs were enrolled.BAL cellular analysis with lymphocyte subsets,and chest CT scan findings were analyzed and compared as per disease subgroup. <b>RESULTS:</b> The mean age was63.5years.The following diseases were studied:idiopathic pulmonary fibrosisIPF(n=2);hypersensitivity pneumonitis HP (n=12);sarcoidosis(n=9);connective tissue diseases(n=6)and pneumoconiosis(N=6).Cytological examination of BAL was carried.Mean cell count in BAL fluid was 200±121.10³cells/ml. Isolated lymphocytic alveolitis was common in sarcoidosis.Mixed alveolitis was the most common pattern in the other interstitial lung diseases. The lymphocyte percentages differed among diagnoses; a greater number of lymphocytes were found in sarcoidosis (66.6%);HP(45.5%)and IPF(20%).MeanCD4/CD8 ratio was 2.49 ± 2.28.It was high in sarcoidosis(median,4.96);the ratio was low in the other DILD,with median values of 2.08 in HP and 0.96 in IPF. A total of 29 participants displayed chest CT scan findings that were indicative of fibrosis.In those cases the percentage of lymphocytes was 37.93 as compared with40.74%of those without fibrosis(p=0.033).In patients with fibrosis in HRCT,the percentage of neutrophils was 27.58% as compared with 14.8% in those without fibrosis. <b>CONCLUSIONS:</b> BAL should be considered a very useful tool in clinical management, particularly when pulmonary biopsy is not conclusive or is not possible.