BRONCHOALVEOLAR LAVAGE

BRONCHOALVEOLAR LAVAGE

Subject : Science & tech

Context : A number of symptomatic patients who tested false negative in RT-PCR assays have subsequently been confirmed Covid-positive in Bronchoalveolar Lavage (BAL) tests.

Concept :

• 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.
• Bronchoalveolar lavage can be a more sensitive method of detection than nasal swabs in respiratory molecular diagnostics, as has been the case with SARS-CoV-2 where bronchoalveolar lavage samples detect copies of viral RNA after negative nasal swab testing.
• In particular, bronchoalveolar lavage is commonly used to diagnose infections in people with immune system problems, pneumonia in people on ventilators, and acute respiratory distress syndrome (ARDS).