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Rationale: Primary ciliary dyskinesia (PCD) is an autosomal recessive, genetically heterogeneous disorder characterised by oto-sino-pulmonary disease and situs abnormalities (Kartagener syndrome) due to abnormal structure and/or function of cilia. Most patients currently recognised to have PCD have ultrastructural defects of cilia; however, some patients have clinical manifestations of PCD and low levels of nasal nitric oxide, but normal ultrastructure, including a few patients with biallelic mutations in dynein axonemal heavy chain 11 (DNAH11)., Objectives: To test further for mutant DNAH11 as a cause of PCD, DNAH11 was sequenced in patients with a PCD clinical phenotype, but no known genetic aetiology., Methods: 82 exons and intron/exon junctions in DNAH11 were sequenced in 163 unrelated patients with a clinical phenotype of PCD, including those with normal ciliary ultrastructure (n=58), defects in outer and/or inner dynein arms (n=76), radial spoke/central pair defects (n=6), and 23 without definitive ultrastructural results, but who had situs inversus (n=17), or bronchiectasis and/or low nasal nitric oxide (n=6). Additionally, DNAH11 was sequenced in 13 subjects with isolated situs abnormalities to see if mutant DNAH11 could cause situs defects without respiratory disease., Results: Of the 58 unrelated patients with PCD with normal ultrastructure, 13 (22%) had two (biallelic) mutations in DNAH11; and two patients without ultrastructural analysis had biallelic mutations. All mutations were novel and private. None of the patients with dynein arm or radial spoke/central pair defects, or isolated situs abnormalities, had mutations in DNAH11. Of the 35 identified mutant alleles, 24 (69%) were nonsense, insertion/deletion or loss-of-function splice-site mutations., Conclusions: Mutations in DNAH11 are a common cause of PCD in patients without ciliary ultrastructural defects; thus, genetic analysis can be used to ascertain the diagnosis of PCD in this challenging group of patients.

Background: A study was undertaken to assess the reliability of the nasal mucociliary transport test using 99mTc-albumin colloid as a screening test for primary ciliary dyskinesia (PCD) and to compare it with the gold standard nasal biopsy for study of ciliary motility and ultrastructure., Methods: During a 4 year period both tests were performed in 55 children referred with persistent or recurrent respiratory tract infections. Their median age was 4 years (range 1 month to 15 years)., Results: The nasal biopsy results were as follows: PCD, n = 8; secondary ciliary dyskinesia (SCD), n = 19; normal, n = 28. The mucociliary transport test was abnormal in 29 patients (all 8 with PCD, 7/19 with SCD, and 14/28 with a normal biopsy). The sensitivity of the mucociliary transport test to diagnose PCD was therefore 100% (8/8) (95% exact confidence limits 63.06 to 100.00); the specificity was only 55% (26/47) (40.95 to 69.89). The negative predictive value was 100% (26/26) (86.77 to 100.00) and the positive predictive value was 28% (8/29) (12.37 to 47.24)., Conclusion: Mucociliary transport is a non-invasive screening test that can be performed even in infants. The sensitivity of the test is high but its specificity is low. A normal test result excludes PCD.

Background: The airway cilia of patients with primary ciliary dyskinesia (PCD) exhibit several anomalies when studied by transmission electron microscopy, but little is known about the ultrastructural organisation of ciliary membranes in these patients. Freeze fracture replication of airway epithelium from patients with PCD provides a means of achieving high resolution views of cell membrane structure. Ciliary necklaces are a specialised structural feature of ciliary membranes thought to serve as a timing mechanism for ciliary beat, and their characterisation in the cilia of patients with PCD may contribute new insights into the pathophysiology of this syndrome., Methods: The nasal epithelium of three patients with PCD was freeze fractured and replicated with platinum and carbon shadowing. The resultant preparations were examined by transmission electron microscopy and the ciliary necklaces were compared with similar preparations of nasal biopsy specimens from normal healthy subjects., Results: The ciliary necklaces of the three patients with PCD were normal with no overt differences from those of healthy individuals., Conclusions: The defective ciliary motility observed in patients with PCD does not appear to result from membrane dysfunction associated with overt disorganisation of ciliary necklace structure.

Background: Primary ciliary dyskinesia is characterised by chronic rhinosinusitis, chronic bronchial sepsis (usually with bronchiectasis), dextrocardia in approximately 50% of cases, and male infertility. The latter, described in patients attending infertility clinics, results from immotile but viable spermatozoa. Experience in a respiratory clinic suggests that infertility in men is not invariable., Methods: The seminal fluid of 12 men with primary ciliary dyskinesia, six with dextrocardia, who presented consecutively with upper and lower respiratory tract sepsis was examined. Nasal ciliary beating was dyskinetic or absent in all cases, and nasal ciliary ultrastructure was abnormal in those 11 patients examined., Results: Viable but immotile spermatozoa with abnormal tail ultrastructure were found in the ejaculate of only two patients. Two other patients had apparently fathered children; seminology in both these cases showed a normal spermatozoa count, one with normal spermatozoal motility and normal ultrastructure, the other with moderately reduced spermatozoal motility and abnormal ultrastructure (dynein arm deficiency on the peripheral microtubule doublets). A further two patients had normal spermatozoa counts, normal spermatozoa tail ultrastructure, and normal or only moderately reduced motility of spermatozoa. The spermatozoa of one patient were normally motile but there was severe oligozoospermia, and five patients were azoospermic., Conclusions: Not all men with primary ciliary dyskinesia have immotile spermatozoa. Seminal analysis is recommended in men with primary ciliary dyskinesia so that accurate counselling about reproductive capability may be given.

Random ciliary orientation has recently been proposed as a variant of primary ciliary dyskinesia. We report a 12 year old boy with all the features of primary ciliary dyskinesia and absent nasal mucociliary clearance in whom repeated biopsies of the nasal epithelium showed normal ciliary beat frequency. The only abnormality discovered was disorientation of the central microtubules of his cilia.

Background: Mucociliary clearance is impaired in patients with Young's syndrome (obstructive azoospermia with recurrent sinobronchial disease), cystic fibrosis, and primary ciliary dyskinesia. No defect of cilia or mucus has been detected in Young's syndrome., Methods: Ciliary function and ultrastructure, including ciliary orientation, were studied quantitatively in 20 patients with Young's syndrome and 20 normal subjects to determine the incidences of ciliary defects. Nasal ciliated epithelium was obtained from each subject and used for measurement of ciliary beat frequency and ultrastructural analyses. Ciliary orientation was determined by measuring ciliary deviation in electron micrographs; ciliary deviation is a measure of the relative orientation of cilia in relation to each other in which high values indicate ciliary disorientation., Results: Ciliary beat frequency and the incidence of microtubular defects and numbers of dynein arms did not differ between patients with Young's syndrome and control subjects. In patients with Young's syndrome basal ciliary deviation (16.0 degrees) was similar to that in control subjects (14.1 degrees), but at the ciliary tip ciliary deviation (21.9 degrees) was greater than in healthy subjects (14.5 degrees)., Conclusion: The relative disorientation of the distal ciliary axoneme in patients with Young's syndrome compared with normal subjects may be due to a structural defect but is more likely to be a consequence of abnormal mucus.