Utility of Bronchoalveolar Lavage, Bronchial Brushing, and Transbronchial Needle Aspiration in Nonneoplastic Lung Diseases – A Single-Center Experience

Abstract

Context: Accurate diagnosis may be challenging in nonneoplastic lung diseases. Newer techniques such as bronchoalveolar lavage (BAL), bronchial brushing (BB), and transbronchial needle aspiration (TBNA) have been studied mainly in lung cancers. Aim: This study assesses the efficacy of BAL, BB, and TBNA in non-neoplastic lung diseases, against a gold standard of transbronchial lung biopsy (TBLB). Settings and Design: Three-year prospective study in a tertiary care center in North India. Methodology: Adult patients (n = 137) with nonimproving respiratory complaints and clinical and radiological suspicion of having a pulmonary pathology were recruited. Patients of malignancy were excluded. Patients for whom all four samples of BAL, BB, TBNA, and TBLB were unavailable were excluded. Statistical Analysis Used: Sensitivity (SN), specificity (SP), positive predictive value, and negative predictive value for all tests were computed and represented with 95% confidence intervals. TBLB was taken to be the gold standard. Two or more tests taken in combination were also analyzed. Results: We studied the patients of tuberculosis, interstitial pneumonia, acute and chronic nonspecific inflammation, sarcoidosis, fungal infection, interstitial lung disease, eosinophilic pneumonitis, and pulmonary alveolar proteinosis in this study. TBNA had higher SN and SP (59.8% and 96.7%) than BB (57.0% and 93.3%) or BAL (54.2% and 86.7%). When combined, SN increased to 68.2% and SP decreased to 76.7%. Diagnostic yield for interstitial pneumonia and chronic inflammation was relatively high but poor for tuberculosis and sarcoidosis. Conclusions: TBNA had the highest SN and SP in diagnosing the various nonneoplastic lesions. However, BAL and BB are useful and complementary tools in the definitive diagnosis of localized and diffuse pulmonary infections.