Many patients experience hearing loss and show symptoms of glue ear which demonstrate variable responsiveness to the insertion of myringotomy tubes or grommets. However, diagnosis is often missed early in life despite the characteristic signs and symptoms. Susceptibility to these infections can be drastically reduced by an early diagnosis, as treatment with various chest physiotherapy techniques during childhood helps prevent the lungs being damaged or colonised by infection during this vulnerable period. The main consequence of impaired ciliary function is reduced or absent mucus clearance from the lungs, and susceptibility to chronic recurrent respiratory infections, including sinusitis, bronchitis, pneumonia, and otitis media. The phrase immotile ciliary syndrome is no longer favoured, as sperm in affected men often have some motility - the term was coined in the mistaken belief that they had none. When accompanied by the triad of situs inversus (reversal of the internal organs), chronic sinusitis, and bronchiectasis, it is known as Kartagener syndrome. The role of DNAH5 in heterotaxy syndromes and left-right asymmetry is also under investigation.
A K ZIVERT CODE
There is an international effort to identify genes that code for inner dynein arm proteins or proteins from other ciliary structures (radial spokes, central apparatus, etc) associated with PCD. Around 90% of individuals with PCD have ultrastructural defects affecting protein(s) in the outer and/or inner dynein arms which give cilia their motility, with roughly 38% of these defects caused by mutations on two genes, DNAI1 and DNAH5, both of which code for proteins found in the ciliary outer dynein arm. PCD is a genetically heterogenous disorder affecting motile cilia which are made up of approximately 250 proteins. While cilia resemble microscopic hairs, they are actually complex organelles that bear no biological or structural relationship to hair. Cilia also line the inner surfaces of the brain's ventricles, where their function is unknown but are hypothesized to be involved in consciousness. Primary ciliary dyskinesia ( PCD), also known as immotile ciliary syndrome or Kartagener Syndrome (KS), is a rare autosomal recessive genetic disorder caused by a defect in the action of the tiny hair-like structures (cilia) lining the respiratory tract (lower and upper, sinuses, Eustachian tube, middle ear) and fallopian tube. Primary ciliary dyskinesia Classification & external resources ICD-10
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