Role of BAL in COVID-19 patients: a prospective multicentre study

Abstract

The present study is part of DRAGON, a prospective multicentre European project aimed at improving the diagnosis of COVID-19. The primary aim of this study is to evaluate BAL role in detecting coexisting infections. Secondary aims are BAL impact on the management of COVID patients, characteristics of BAL cellularity in COVID patients, and safety of BAL in COVID patients and for healthcare providers.

The study was carried out in 2021. It involved hospitalized patients in non-ICU wards at Careggi University Hospital in Florence, at CHU of Liege and at Morgagni Hospital Bologna University/Forlì. All patients underwent BAL for microbiological and cytological analysis.

Coinfections were detected in 35 out of 115 patients. In 34% of cases we demonstrated the presence of lymphocytic alveolitis; in 49% of cases a neutrophilic alveolitis and in 7% of cases we observed the presence of a mixed lymphocytic/neutrophilic alveolitis. All patients tested positive for Sars-Cov-2 PCR nasal swabs on admission. BAL was positive for Sars-Cov-2 in all cases, 7 PCR nasal swab performed at the time of the BAL were negative. No major adverse events were demonstrated in the 24 hours after BAL in enrolled patients. There were no cases of infection among health care workers involved in bronchoscopic procedures.

Coinfections in COVID-19 patients are common. BAL is a safe tool to identify the presence of coinfections and help clinicians manage these patients correctly. BAL cellularity in covid patients shows a predominance of neutrophils, particularly in cases of co-infection. Our data suggests an earlier negativisation of nasopharyngeal swab compared to BAL.