TY - JOUR T1 - Sputum procalcitonin – a potential biomarker in stable bronchiectasis JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00285-2021 SP - 00285-2021 AU - William Good AU - Gene Jeon AU - Irene Zeng AU - Louanne Storey AU - Helen Qiao AU - Stuart Jones AU - Sarah Mooney AU - Lata Jayaram AU - David Holland AU - Conroy Wong Y1 - 2021/01/01 UR - http://openres.ersjournals.com/content/early/2021/07/15/23120541.00285-2021.abstract N2 - Introduction/Aim Sputum procalcitonin has been demonstrated to be elevated in exacerbations of bronchiectasis. The primary aim was to investigate whether sputum procalcitonin levels were higher in patients with stable bronchiectasis compared with healthy-controls. We also assessed differences in procalcitonin levels in spontaneously expectorated and induced sputum samples and their repeatability one week later.Methods Participants included were aged over 18 years and had either radiologically confirmed bronchiectasis or were healthy-controls. Patients with bronchiectasis were clinically stable for at least six weeks and had both spontaneous and induced sputum collected at visit one and again, seven days later. Only induced sputum samples were collected from healthy-controls during visit one. Sputum procalcitonin concentrations in sputum were measured.Results Thirty patients with bronchiectasis and 15 healthy-controls were enrolled in this observational study. In the pooled data from visit 1 and 2, the geometric mean procalcitonin level in induced sputum was significantly higher in the bronchiectasis group than in the healthy-control group (1.5 ng·mL−1 [95%CI 1.0–2.1] versus 0.4 ng·mL−1 [95%CI 0.2–0.9], mean ratio: 3.6 [95% CI 1.5–8.6], p=0.006). Mean procalcitonin level was higher in spontaneous sputum than in induced sputum at visit 1 (1.8 ng·mL−1 [95%CI 1.2–2.7] versus 1.1 ng·mL−1 [95%CI 0.7–1.8]) and visit 2 (1.5 ng·mL−1 [95%CI 1.0–2.5] versus 1.2 ng·mL−1 [95%CI 0.8–1.6], p-value=0.001). Repeating spontaneous and induced sputum procalcitonin levels one week later produced similar concentrations (p-value=0.29; intraclass correlation co-efficient (ICC)=0.76 and p-value=0.72; ICC=0.70 respectively).Conclusion Sputum procalcitonin is increased in patients with stable bronchiectasis and has potential as a biomarker of airway inflammation and infection in bronchiectasis.FootnotesThis manuscript has recently been accepted for publication in the ERJ Open Research. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJOR online. Please open or download the PDF to view this article.Conflict of interest: Dr William Good does not have a conflict of interest to disclose.Conflict of interest: Gene Jeon has nothing to disclose.Conflict of interest: Dr Zeng has no conflict of interest to disclose.Conflict of interest: Dr Storey has no conflict of interest to disclose.Conflict of interest: Dr. Qiao has nothing to disclose.Conflict of interest: Dr. Jones has nothing to disclose.Conflict of interest: Dr. Mooney has nothing to disclose.Conflict of interest: Associate Professor Jayaram has no conflict of interest to disclose.Conflict of interest: Dr. Holland has nothing to disclose.Conflict of interest: Dr. Wong has nothing to disclose. ER -