Abstract

BACKGROUND

Reverse-transcriptase polymerase chain reaction (RT-qPCR) assays performed on respiratory samples collected through nasal swabs still represent the gold standard for COVID-19 diagnosis. Alternative methods to this invasive and time-consuming options are still being inquired, including the collection of airways lining fluids through exhaled breath condensate (EBC).

MATERIALS AND METHODS

We performed a systematic review and meta-analysis in order to explore the reliability of EBC as a way to collect respiratory specimens for RT-qPCR for diagnosis of COVID-19.

RESULTS

A total of 4 studies (205 specimens), were ultimately collected, with a pooled sensitivity of 69.5% (95%CI 26.8-93.4), and a pooled specificity of 98.3% (95%CI 87.8-99.8), associated with high heterogeneity and scarce diagnostic agreement with the gold standard represented by nasal swabs (Cohen's kappa = 0.585).

DISCUSSION

Even though non-invasive options for diagnosis of COVID-19 are still necessary, EBC-based RT-qPCR showed scarce diagnostic performances, ultimately impairing its implementation in real-world settings. However, as few studies have been carried out to date, and the studies included in the present review are characterized by low numbers and low sample power, further research are requested to fully characterize the actual reliability of EBC-based RT-qPCR in the diagnosis of COVID-19.

MeSH

Infections, Diagnosis, Sars Virus, Covid-19, Sars-Cov-2

Cited by

• New perspectives on 'Breathomics': metabolomic profiling of non-volatile organic compounds in exhaled breath using DI-FT-ICR-MS. Commun Biol, 2024
• A comprehensive meta-analysis and systematic review of breath analysis in detection of COVID-19 through Volatile organic compounds. Diagn Microbiol Infect Dis, 2024
• Diagnosis of SARS-CoV-2 infection from breath - a proof-of-concept study. IJID Reg, 2022
• Severe acute respiratory syndrome coronavirus-2 shedding in exhaled material: a systematic review. Epidemiol Infect, 2025