Data on primary ciliary dyskinesia (PCD) epidemiology is scarce and published studies are characterised by low numbers. In the framework of the European Union project BESTCILIA we aimed to combine all available datasets in a retrospective international PCD cohort (iPCD Cohort). We identified eligible datasets by performing a systematic review of published studies containing clinical information on PCD, and by contacting members of past and current European Respiratory Society Task Forces on PCD. We compared the contents of the datasets, clarified definitions and pooled them in a standardised format. As of April 2016 the iPCD Cohort includes data on 3013 patients from 18 countries. It includes data on diagnostic evaluations, symptoms, lung function, growth and treatments. Longitudinal data are currently available for 542 patients. The extent of clinical details per patient varies between centres. More than 50% of patients have a definite PCD diagnosis based on recent guidelines. Children aged 10–19 years are the largest age group, followed by younger children (⩽9 years) and young adults (20–29 years). This is the largest observational PCD dataset available to date. It will allow us to answer pertinent questions on clinical phenotype, disease severity, prognosis and effect of treatments, and to investigate genotype–phenotype correlations.
This article has supplementary material available from erj.ersjournals.com ; The diagnosis of primary ciliary dyskinesia is often confirmed with standard, albeit complex and expensive, tests. In many cases, however, the diagnosis remains difficult despite the array of sophisticated diagnostic tests. There is no "gold standard" reference test. Hence, a Task Force supported by the European Respiratory Society has developed this guideline to provide evidence-based recommendations on diagnostic testing, especially in light of new developments in such tests, and the need for robust diagnoses of patients who might enter randomised controlled trials of treatments. The guideline is based on pre-defined questions relevant for clinical care, a systematic review of the literature, and assessment of the evidence using the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach. It focuses on clinical presentation, nasal nitric oxide, analysis of ciliary beat frequency and pattern by high-speed video-microscopy analysis, transmission electron microscopy, genotyping and immunofluorescence. It then used a modified Delphi survey to develop an algorithm for the use of diagnostic tests to definitively confirm and exclude the diagnosis of primary ciliary dyskinesia; and to provide advice when the diagnosis was not conclusive. Finally, this guideline proposes a set of quality criteria for future research on the validity of diagnostic methods for primary ciliary dyskinesia. ; J.S. Lucas, K.G. Nielsen, C.E Kuehni, C. Hogg, M.W Leigh and H. Omran received funding from the European Union Seventh Framework Programme (FP7/2007–2013) under grant agreement n8305404 (BESTCILIA). J.S. Lucas, L. Behan, W.T. Walker and S.A. Collins were supported by the NIHR Respiratory Biomedical Research Unit at the University Hospital Southampton NHS Foundation Trust (Southampton, UK) and AAIR Charity. A. Bush is an NIHR Senior Investigator and was supported by the NIHR Respiratory Disease Biomedical Research Unit at the Royal Brompton and Harefield NHS Foundation Trust and Imperial College London (both London, UK). M. Goutaki was supported by the following national grants: Bernese Lung League, Milena- Pro Kartagener foundation and Swiss National Foundation 32003B_162820/1. S. Dell and M.W. Leigh received funding from the NIH (U54HL096458) through the Genetic Disorders of Mucociliary Clearance Consortium, an initiative of the NIH Office of Rare Diseases Research at the National Center for Advancing Translational Science, and the National Heart, Lung and Blood Institute. ; Peer-reviewed ; Post-print