Journal of Molecular Pathology and Biochemistry
Open Access

Bronchoalveolar Lavage

Bronchoalveolar lavage (BAL) (also known as bronchoalveolar washing) is a diagnostic method of the lower respiratory system in which a bronchoscope is passed through the mouth or nose into an appropriate airway in the lungs, with a measured amount of fluid introduced and then collected for examination. This method is typically performed to diagnose pathogenic infections of the lower respiratory airways(leading to, for example pneumonia and COVID-19[), though it also has been shown to have utility in diagnosing interstitial lung disease.