Primary ciliary dyskinesia (PCD), or immotile cilia syndrome, is viewed as an unusual cause of persistent wheezing and cough in children. Occurring in approximately 1 in 7,500 to 20,000 births, PCD is a genetic disorder that results from ultrastructural abnormalities of the cilia. Ciliary dysfunction causes impaired mucociliary clearance, which results in the retention of inhaled particles, including bacteria, in the lung, paranasal sinuses, and middle ear. The abnormal mucociliary clearance of airway secretions causes a chronic bronchitis, and wheezing is a common clinical manifestation due to the mucus obstruction of the airways. The course of lung disease is not well defined, and its progression varies, including microbial colonization of the lower respiratory tract and development of bronchiectasis.
Primary ciliary dyskinesia has several non-pulmonary manifestations. Repeated or persistent severe upper respiratory tract infections, typically chronic pansinusitis or suppurative otitis media, occur in virtually every patient with "classic" forms of the disease. Although Kartagener initially described several patients who presented with situs inversus totalis, chronic sinusitis and bronchiectasis, situs inversus is present in only half of the cases of this syndrome. The occurrence of situs inversus totalis is random and not genetically predetermined, even within affected families. Male sterility due to the impaired movement of spermatozoa also occurs, and infertility may be the presenting feature of the disease. Cardiac anomalies and hydrocephalus have also been described in affected patients.
In this consortium, we plan to improve diagnostic testing of PCD, understand the pathogenesis, clinical presentations, and better define clinical outcomes of the disease.