TY - JOUR T1 - Nasal Nitric Oxide Sampling In 0-5-year-old Patients With Cystic Fibrosis, Primary Ciliary Dyskinesia and Healthy Controls JF - European Respiratory Journal JO - Eur Respir J DO - 10.1183/13993003.congress-2021.PA3158 VL - 58 IS - suppl 65 SP - PA3158 AU - Maja Valentin Kragh AU - Mathias G. Holgersen AU - June K. Marthin AU - Kim G. Nielsen Y1 - 2021/09/05 UR - http://erj.ersjournals.com/content/58/suppl_65/PA3158.abstract N2 - Introduction: Nasal nitric oxide (nNO) is extremely low in individuals with primary ciliary dyskinesia (PCD) and is recommended as part of early workup. We investigated the results of a former study whether tidal breathing sampling for a few seconds and vacuum sampling was as discriminative between PCD and healthy controls (HC) as conventional tidal breathing sampling (cTB-nNO) for 20–30s.Methods: We performed very rapid sampling of tidal breathing for 4 s (TB-nNO4sec) and vacuum sampling with applied negative pressure (TB-nNOvac; negative pressure was applied by pinching the sampling tube) for < 2 s resulted in enhanced suction of nasal air during measurement. Feasibility, success rate, discriminatory capacity, repeatability and agreement were assessed the three sampling modalities.Results: We included 5 patients with PCD, median (IQR) age of 1.2 (0.3-4.1) years and 13 HC, 3.4 (1.3–4.4) years and 8 patients with cystic fibrosis (CF) as a disease control group, 2.4 (0.4–2.9) years. Measured nNO values with TB-nNO4sec and TB-nNOvac showed similar and comparable results to cTB-nNO measurements (HC4sec: p = 0.11, HCvac: p = 0.87, PCD4sec: p = 0.56, PCDvac: p = 0.23, CF4sec: p = 0.38, CFvac: p = 0.06).Conclusion: TB-nNO4sec and TB-nNOvac were comparable to cTB-nNO. TB-nNO4sec and TB-nNOvac requires only a few seconds of probe-in-nose time and is feasible for preschool kids and infants (0-5 years). Rapid TB-nNO sampling needs standardization and further investigations.Keywords: Primary ciliary dyskinesia · Nasal nitric oxide · Rare lung diseases · Pediatrics · Cystic fibrosisFootnotesCite this article as: European Respiratory Journal 2021; 58: Suppl. 65, PA3158.This abstract was presented at the 2021 ERS International Congress, in session “Prediction of exacerbations in patients with COPD”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only). ER -