An infant with respiratory distress and failure to thrive

Clinical and genetic aspects of primary ciliary dyskinesia/Kartagener syndrome

Primary ciliary dyskinesia is a genetically heterogeneous disorder of motile cilia. Most of the disease-causing mutations identified to date involve the heavy (dynein axonemal heavy chain 5) or intermediate(dynein axonemal intermediate chain 1) chain dynein genes in ciliary outer dynein arms, although a few mutations have been noted in other genes. Clinical molecular genetic testing for primary ciliary dyskinesia is available for the most common mutations. The respiratory manifestations of primary ciliary dyskinesia (chronic bronchitis leading to bronchiectasis, chronic rhino-sinusitis, and chronic otitis media)reflect impaired mucociliary clearance owing to defective axonemal structure. Ciliary ultrastructural analysis in most patients (>80%) reveals defective dynein arms, although defects in other axonemal components have also been observed. Approximately 50% of patients with primary ciliary dyskinesia have laterality defects (including situs inversus totalis and, less commonly, heterotaxy, and congenital heart disease),reflecting dysfunction of embryological nodal cilia. Male infertility is common and reflects defects in sperm tail axonemes. Most patients with primary ciliary dyskinesia have a history of neonatal respiratory distress, suggesting that motile cilia play a role in fluid clearance during the transition from a fetal to neonatal lung. Ciliopathies involving sensory cilia, including autosomal dominant or recessive polycystic kidney disease, Bardet-Biedl syndrome, and Alstrom syndrome, may have chronic respiratory symptoms and even bronchiectasis suggesting clinical overlap with primary ciliary dyskinesia.

Evaluation of residual functional lung volume on Tc-99m DTPA aerosol ventilation and Tc-99m MAA perfusion scintigraphy in primary ciliary dyskinesia (Kartagener syndrome)

Kartagener syndrome is diagnosed as sinusitis, bronchitis (bronchiectasis), and situs inversus by the clinical features. It is a subclass of primary ciliary dyskinesia (PCD) disease. A 12-year-old girl who had frequent upper and lower airway infections since birth, which was confirmed as Kartagener syndrome by HRCT imaging. We present the residual functional lung volume and mucociliary clearance findings seen on Tc-99m DTPA aerosol ventilation and Tc-99m MAA perfusion scintigraphy.

Primary ciliary dyskinesia: recent advances in pathogenesis, diagnosis and treatment

Primary ciliary dyskinesia is a genetic disorder causing dysfunctional motility of cilia and impaired mucociliary clearance, resulting in a myriad of clinical manifestations including recurrent sinopulmonary disease, laterality defects and infertility. The heterogenous clinical presentation of primary ciliary dyskinesia and the limitations of transmission electron microscopy to assess ultrastructural defects within the cilium often delay diagnosis. Recent advances in the understanding of the basic biology and function of the cilium have led to potential diagnostic alternatives, including ciliary beat analysis and nasal nitric oxide measurements. Moreover, the identification of disease-causing mutations could lead to the development of comprehensive genetic testing that may overcome many of the current diagnostic limitations. Although the clinical manifestations of primary ciliary dyskinesia have been recognised for over a century, there are few studies examining treatments and standards of care have yet to be established. Multicentre collaborative efforts have been established in North America and Europe, which should help to develop standardised approaches to the diagnosis and treatment of primary ciliary dyskinesia.