Diagnostic agreement between bronchoalveolar lavage and transbronchial lung biopsy in patients with suspected pulmonary diseases: A single-center study.

Objective: This study investigates the diagnostic concordance between bronchoalveolar lavage (BAL) cytology and the histologic analysis of transbronchial lung biopsy (TBLB) specimens in patients with suspected pulmonary diseases to highlight the strengths and limitations of these complementary diagnostic tools.

Material and methods: We conducted a comprehensive retrospective cross-sectional analysis on patients suspected of pulmonary diseases who underwent both BAL and TBLB from 2018 to 2022. We assessed diagnostic agreement using kappa statistics and calculated the overall concordance rates. The analysis was stratified based on malignant versus infectious etiologies to elucidate performance differences between the two methods.

Results: Our study included a cohort of 189 patients, comprising 104 individuals with suspected malignancy and 85 with suspected infections. Among the malignancy group, BAL yielded positive results for cancer in 49 patients, whereas TBLB confirmed malignancy in 64 patients, demonstrating an overall agreement of 70.19% (kappa = 0.52, 95% confidence interval [CI]: 0.38-0.66). Conversely, within the infectious cohort, BAL identified micro-organisms in only five patients, while TBLB diagnosed infection in 22 patients, achieving an overall agreement of 77.65% (kappa = 0.29, 95% CI: 0.17-0.41).

Conclusion: Our findings underscore the critical role of BAL cytology in the diagnosis of pulmonary carcinoma and infectious processes while also revealing its limitations in detecting interstitial lung diseases. The TBLB procedure emerges as an indispensable technique for accurate histopathological evaluation in lung cancer diagnostics. The integration of BAL and TBLB not only enhances diagnostic yield but also provides a more comprehensive understanding of pulmonary pathologies. Notably, we found moderate agreement between BAL and TBLB in neoplastic cases and fair agreement in non-neoplastic conditions, suggesting a nuanced interplay between these methodologies that could inform clinical practice and improve patient outcomes. This study advocates a combined approach in diagnostic frameworks to optimize the management of patients with suspected pulmonary diseases, paving the way for more precise and effective diagnoses in the field of cytology.