The clinical utility of bronchoalveolar lavage in diffuse parenchymal lung disease.

Bronchoalveolar lavage (BAL) has been used in diagnostic and prognostic evaluation in diffuse parenchymal lung disease for three decades and has a central role in the diagnosis of a number of rare disorders and in excluding opportunistic infection in treated patients. It also has an important place in the personal diagnostic algorithms of many experienced clinicians in the diagnosis of the more prevalent disorders, including sarcoidosis, hypersensitivity pneumonitis and idiopathic pulmonary fibrosis. This use of BAL is not well captured in the medical literature, as most published studies pre-date changes in disease classification and fail to integrate BAL data with other clinical and radiological information. Further studies to quantify the value added by bronchoalveolar lavage in routine practice are urgently required.