Primary ciliary dyskinesia: diagnosis and standards of care.

Primary ciliary dyskinesia (PCD) is characterized by disease of the upper and lower respiratory tract, in association with visceral mirror image arrangement in 50% of cases, due to abnormal structure and/or function of cilia. The purpose of this paper is to review the clinical features, diagnosis and management of PCD. Presentations include neonatal respiratory distress, recurrent lower respiratory tract infection, chronic rhinosinusitis and male infertility. PCD enters the differential diagnosis of bronchiectasis, atypical asthma, and unusually severe upper airway disease. Diagnosis is by a cascade of investigations, starting with the saccharin test in patients older than 10 yrs; ciliary beat frequency and pattern on light microscopy; and electron microscopy to assess ciliary morphology and orientation. It is important not to confuse primary and secondary ciliary abnormalities. Nasal nitric oxide is low in PCD, and this measurement shows promise as a screening test for PCD. Diagnosis is important, in order to prevent the development of bronchiectasis and to avoid any unnecessary otorhinolaryngological procedures. Regular follow-up is essential, and management should be multidisciplinary, with input from centres with a special interest in PCD, having access to paediatric and adult chest physicians, otolaryngologists and audiological physicians, physiotherapists, counselling services and fertility clinics. The prognosis is good, but morbidity can be considerable if PCD is incorrectly managed.