Diagnostic Utility of Different Respiratory Clinical Specimens in the COVID-19 Era and Risk of Nosocomial Transmission of SARS-CoV2 with Fibrobronchoscopy and Sputum Induction Procedures

Abstract We wanted to retrospectively examine a series of 229 patients hospitalized between March 2020 and January 2022 to evaluate the role of bronchoscopy and induced sputum for the diagnosis of SARS-CoV2 infection and other lung diseases. Furthermore, we wanted to evaluate the risk of nosocomial transmission of SARS CoV2 infection through the two procedures. Broncho alveolar lavage fluid and induced sputum have been shown to be valuable respiratory specimens for difficult or questionable SARS-CoV2 diagnoses and allow the diagnosis of concomitant respiratory infections in more severe patients. At the same time, by applying an institutional protocol, which involves the use of negative pressure rooms and compliance with airborne, droplet and contact isolation during the execution of these procedures, we have not observed any cases of transmission among dedicated healthcare personnel and among non-COVID19 patients observed during the study period. Since patients often present with multiple respiratory infections at the same time and given the usefulness of these respiratory specimens for their diagnosis, we believe that extending these precautions to all patients undergoing FBS and sputum induction is necessary, regardless of the clinical suspicion of SARS-CoV2 infection.