ORIGINAL RESEARCH article
Front. Mol. Biosci.
Sec. Molecular Diagnostics and Therapeutics
This article is part of the Research TopicDistinct phenotype but same genotype: Hints for the diversity of phenotypes in ciliopathiesView all 5 articles
Limitations of PICADAR as a diagnostic predictive tool for primary ciliary dyskinesia
Provisionally accepted
Heymut Omran1*
Andre Schramm1
Johanna Raidt1Sarah Riepenhausen2Caroline Marie Torp Nygaard3Retno Tenardi-Wenge1Tavs Qvist4Pernille Witt3
Michael Storck2Heike Olbrich1
Kim G Nielsen3- 1Department of General Pediatrics, University Hospital Münster, Münster, Germany
- 2Institute of Medical Informatics, Universitat Munster, Münster, Germany
- 3Department of Pediatrics and Adolescent Medicine, Rigshospitalet, Copenhagen, Denmark
- 4Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark
Select one of your emails
You have multiple emails registered with Frontiers:
Notify me on publication
Please enter your email address:
If you already have an account, please login
You don't have a Frontiers account ? You can register here
Background The Primary Ciliary Dyskinesia Rule (PICADAR) is a diagnostic predictive tool currently recommended by the European Respiratory Society (ERS) to assess the likelihood of a primary ciliary dyskinesia (PCD) diagnosis. Despite its recommendation according to the current ERS PCD diagnostic guideline, the performance of the PICADAR remains insufficiently studied. Methods We evaluated the sensitivity of PICADAR in 269 individuals with genetically confirmed PCD. Using an initial question, PICADAR rates all individuals without daily wet cough negative for PCD. PICADAR evaluates seven questions in the daily wet cough group. We here calculated test sensitivity based on the proportion of individuals scoring ≥5 points as recommended. Subgroup analyses examined the impact of laterality defects and predicted hallmark ultrastructural defects. Results 18 individuals (7%) reported no daily wet cough ruling out PCD according to PICADAR. The median PICADAR score was 7 (IQR: 5 – 9), with an overall sensitivity of 75% (202/269). Sensitivity was higher in individuals with laterality defects (95%; median score: 10; IQR 8-11) compared to those with situs solitus (61%, median score: 6; IQR 4-8; p*<0.0001). Further stratification by associated ciliary ultrastructure showed higher sensitivity in individuals with hallmark defects (83%) versus those without (59%, p*<0.0001). Conclusion The PICADAR has limited sensitivity, particularly in individuals without laterality defects (61%) or absent hallmark ultrastructural defects (59%). Therefore, it PICADAR should not be the only factor to initiate diagnostic work-up forused with caution as the primary factor for estimating the likelihood of PCD. Alternative predictive tools are needed, particularly for PCD individuals with normal body composition and normal ultrastructure.
Keywords: PCD, motile ciliopathy, PICADAR, Predictive tool, score, test sensitivity, ciliaryultrastructure, Situs Inversus
Received: 24 Aug 2025; Accepted: 11 Nov 2025.
Copyright: © 2025 Omran, Schramm, Raidt, Riepenhausen, Nygaard, Tenardi-Wenge, Qvist, Witt, Storck, Olbrich and Nielsen. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Heymut Omran, heymut.omran@ukmuenster.de
Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.