COVID-19 infections: Bronchoscopy provides additional diagnostic certainty

Findings from a retrospective analysis of bronchoscopy results suggest that a bronchoscopy may add diagnostic value in patients with unclear COVID-19 diagnosis [1].

“Reliable tests with a high negative predictive value can help to defer non-COVID patients to a normal ward without isolation and preserve isolation rooms for COVID-19 patients,” said Dr Thomas Malfait (Ghent University Hospital, Belgium). Thus, clinicians are in need of fast and reliable diagnostic results. The current gold-standard for confirmation of a suspected COVID-19 infection is a real-time reverse transcriptase-polymerase chain reaction (rRT-PCR), and specimens taken by bronchoalveolar lavage (BAL) show the highest rate of positivity in rRT-PCR [2,3]. However, recommendations have been in favour of postponing bronchoscopy to protect healthcare workers. Due to this advice, the diagnostic value of bronchoscopy in this setting is not yet known. Thus, Dr Malfait and his fellow investigators retrospectively evaluated the results of video bronchoscopies performed between 19 March and 5 May 2020.

The added diagnostic certainty was classified as: alternative microbiological diagnosis in the BAL fluid or SARS-CoV-2 PCR positivity or negativity in BAL fluid. The indication for performing video bronchoscopies was a diagnostic uncertainty in patients that had repetitive negative PCR swabs but high clinical indicators of COVID-19 and a positive chest CT (n=31), or COVID-19 positive patients (n=7) with suspected alternative pathologies such as a superinfection.

The results for the first group showed rRT-PCR positivity in 7 cases, 9 patients that were truly negative (i.e. negative rRT-PCR) and 15 alternative microbiological diagnoses. In the group of COVID-19 positive patients, an additional microbiological diagnosis was detected in 5 out of 7 cases. Taken together, 95% of the 38 bronchoscopies resulted in additional diagnostic certainty. All video bronchoscopies were performed on haemodynamically stable or ventilated patients, using personal protection equipment, preferably as bedside procedure. There were no bronchoscopy-related adverse events, nor COVID-19 infections in involved staff.

“In suspected COVID-19 cases with diagnostic uncertainty, bronchoscopy has an additional diagnostic value with therapeutic consequences, provided safety standards are ensured. There is a high yield in alternative diagnoses and the negative predictive value for contagiousness seems to be high,” concluded Dr Malfait.

 

1. 
   
   1. Malfait T, et al. The role of bronchoscopy in COVID-19 patients during the SARS-CoV-2 pandemic. LBA 4146, ERS International Virtual Congress 2020, 7-9 Sept.
   2. European Centre for Disease Prevention and Control. June 2020. Retrieved from: https://www.ecdc.europa.eu/en/covid-19/latest-evidence/diagnostic-testing [Accessed on 30 Sept 2020].
   3. Wang W, et al. JAMA. 2020;323:1843-1844.

 



Posted on 29 October 2020