Purpose of review: To evaluate the role of bronchoalveolar lavage in the diagnosis of diffuse parenchymal lung diseases and review the recent literature published within the past 12 months.
Recent findings: Diffuse parenchymal lung diseases are a heterogeneous group of disorders originating from the distal lung parenchyma. Despite different etiologies, the clinico-radiologic findings are usually alike and diagnosis can be challenging. Bronchoalveolar lavage and the analysis of cell counts are routine investigations for this group of disorders. Not only it can be used to see serial changes, it also important for providing information from a broader lung area. Although rarely diagnostic for a particular etiology, the predictive value of bronchoalveolar lavage differentials are reported to make some diagnoses more likely and exclude others like infections and tumors. This result is especially significant for the frequently encountered diffuse parenchymal diseases like sarcoidosis, usual interstitial pneumonia or extrinsic allergic alveolitis.
Summary: Bronchoalveolar lavage is a convenient and safe procedure to apply for the diagnosis of diffuse parenchymal lung diseases especially to provide more information of the likelihood of the more common forms like sarcoidosis, extrinsic allergic alveolitis and usual interstitial pneumonia.