Assessment of an Exhaled Breath Test to Detect Bronchiectasis

All exhaled breath samples were collected by trained investigators following the same protocol. All participants fasted for at least 6 hours before breath collection. To reduce potential confounding factors, all participants were asked to not ingest spicy food, alcohol, or coffee the night before exhaled breath collection. Exhaled breath was collected in Tedlar air bags (DuPont de Nemours). The night before breath collection, the Tedlar bags were baked at 60 °C for 3 hours to fully release possible contaminants and continuously purged with high-purity nitrogen 4 times. Participants first gargled with pure water and then performed a single deep nasal inhalation followed by complete exhalation via their mouth into Tedlar bags. A total of 1000 mL of exhaled breath was collected from each participant. Breath sample detection was based on the HPPI-TOFMS platform.