Genome sequencing reveals underdiagnosis of primary ciliary dyskinesia in bronchiectasis
Amelia Shoemark, Helen Griffin, Gabrielle Wheway, Claire Hogg, Jane S. Lucas, Carlos Camps, Jenny C. Taylor, Mary Carroll, Michael R. Loebinger, James D. Chalmers, Déborah Morris-Rosendahl, Hannah M. Mitchison, Anthony De Soyza, David E. Brown, John C. Ambrose, Prabhu Arumugam, R. Bevers, Marta Bleda, F. Boardman-Pretty, C. R. Boustred, Helen Brittain, Mark J. Caulfield, G. C. Chan, Tom Fowler, Adam Giess, Angela Hamblin, Shirley Henderson, Tim Hubbard, Richard V. Jackson, J. Louise Jones, Dalia Kasperavičiūtė, Melis Kayikci, Athanasios Kousathanas, L. Lahnstein, S. E. A. Leigh, Ivone Leong, Fabrice Lopez, F. Maleady-Crowe, Meriel McEntagart, Federico Minneci, Loukas Moutsianas, Marcus Mueller, Nirupa Murugaesu, Anna C. Need, Peter O’Donovan, Chris A. Odhams, Christine Patch, D. Perez-Gil, Mariana Buongermino Pereira, J. Pullinger, T. Rahim, Álvaro Rendón, T. Rogers, K. Savage, K. Sawant, Richard H. Scott, Afshan Siddiq, A. Sieghart, Samuel C. Smith, Alona Sosinsky, A. Stuckey, M. Tanguy, Ana Lisa Taylor Tavares, Ellen Thomas, Simon R. Thompson, Arianna Tucci, M. J. Welland, Elyse T. Williams, Katarzyna Witkowska, S. M. Wood
Abstract
BACKGROUND: Bronchiectasis can result from infectious, genetic, immunological and allergic causes. 60-80% of cases are idiopathic, but a well-recognised genetic cause is the motile ciliopathy, primary ciliary dyskinesia (PCD). Diagnosis of PCD has management implications including addressing comorbidities, implementing genetic and fertility counselling and future access to PCD-specific treatments. Diagnostic testing can be complex; however, PCD genetic testing is moving rapidly from research into clinical diagnostics and would confirm the cause of bronchiectasis. METHODS: This observational study used genetic data from severe bronchiectasis patients recruited to the UK 100,000 Genomes Project and patients referred for gene panel testing within a tertiary respiratory hospital. Patients referred for genetic testing due to clinical suspicion of PCD were excluded from both analyses. Data were accessed from the British Thoracic Society audit, to investigate whether motile ciliopathies are underdiagnosed in people with bronchiectasis in the UK. RESULTS: Pathogenic or likely pathogenic variants were identified in motile ciliopathy genes in 17 (12%) out of 142 individuals by whole-genome sequencing. Similarly, in a single centre with access to pathological diagnostic facilities, 5-10% of patients received a PCD diagnosis by gene panel, often linked to normal/inconclusive nasal nitric oxide and cilia functional test results. In 4898 audited patients with bronchiectasis, <2% were tested for PCD and <1% received genetic testing. CONCLUSIONS: PCD is underdiagnosed as a cause of bronchiectasis. Increased uptake of genetic testing may help to identify bronchiectasis due to motile ciliopathies and ensure appropriate management.