PCDSOS: a novel clinical predictive tool for screening primary ciliary dyskinesia in adult bronchiectasis patients-a multicenter derivation and external validation study.

Abstract

Primary ciliary dyskinesia (PCD) is a rare but underdiagnosed genetic cause of adult bronchiectasis, with current predictive tools (e.g., PICADAR, NA-CDCF) primarily validated in children and lacking adult-specific predictors (e.g., subfertility). This study aimed to develop and validate a practical tool (PCDSOS) for PCD screening in adult bronchiectasis. Derivation group (n = 287) from Peking Union Medical College Hospital (2013-2025) and validation group (n = 107) from The Second Xiangya Hospital (2016-2024) were included. All patients completed ≥ 1 PCD diagnostic test (nasal nitric oxide, whole-exome sequencing, transmission electron microscopy, or high-speed video microscopy analysis). Logistic regression was used to develop PCDSOS, with performance assessed by AUC, calibration curve, and decision curve analysis. Existing tools showed reduced accuracy in adults (AUC: 0.76-0.85 vs. 0.84-0.98 in original studies). PCDSOS included 6 predictors: pulmonary atelectasis/lobectomy in middle lobe/lingula (P, 2 points), neonatal chest symptoms (C, 2 points), organ laterality defects (D, 5 points), chronic sinusitis (S, 2 points), chronic otitis media/hearing loss from childhood (O, 1 point), and subfertility (S, 1 point). At cutoff = 3, PCDSOS had sensitivity 0.86, specificity 0.76 (derivation cohort, AUC = 0.90) and sensitivity 0.90, specificity 0.67 (validation cohort, AUC = 0.92). A free web-based version of PCDSOS for automated scoring is available to facilitate clinical application. PCDSOS outperforms existing tools in adult bronchiectasis, providing a cost-effective screening strategy to identify patients requiring further PCD diagnostic testing-critical for preventing irreversible lung damage and guiding genetic counseling.