Lung Disease In Primary Ciliary Dyskinesia Research Articles

Pediatric unilobar resection in primary ciliary dyskinesia.

Primary ciliary dyskinesia (PCD) causes chronic infections and progressive bronchiectasis that can lead to severe lung disease. Because there are no cures or regenerative therapy options for PCD, treatment of severe lung disease in PCD is focused on managing symptoms, including aggressive administration of antibiotics and diligent airway clearance. The Genetic Disorders of Mucociliary Clearance Consortium (GDMCC) does not recommend routine lobectomy, reserving its use for "rare cases of PCD with severe, localized bronchiectasis" and warns that a lobectomy should be treated with caution. However, if aggressive medical management fails, selective surgical removal of severely defective lung may result in maintenance or improvement of pulmonary function. Certainly, the decision to recommend lung resection in the face of chronic bronchiectasis from PCD requires an extensive discussion before it is considered as an alternative treatment. The purpose of this manuscript was to demonstrate that in selected cases of unilobar disease with bronchiectasis that are not responsive to other therapies (antibiotics and airway clearance), removal of localized necrotic areas of the lung along with prophylactic antibiotics can improve the quality of life of children with PCD associated bronchiectasis and improve growth and nutritional status, and pulmonary function.

Chronic airway disease in primary ciliary dyskinesia-spiced with geno-phenotype associations.

Primary ciliary dyskinesia (PCD) can be defined as a multiorgan ciliopathy with a dominant element of chronic airway disease affecting the nose, sinuses, middle ear, and in particular, the lower airways. Although most patients with PCD are diagnosed during preschool years, it is obvious that the chronic lung disease starts its course already from birth. The many faces of the clinical picture change, as does lung function, structural lung damage, the burden of infection, and of treatment throughout life. A markedly severe neutrophil inflammation in the respiratory tract seems pervasive and is only to a minimal extent ameliorated by a treatment strategy, which is predominantly aimed at bacterial infections. An ever‐increasing understanding of the different aspects, their interrelationships, and possible different age courses conditioned by the underlying genotype is the focus of much attention. The future is likely to offer personalized medicine in the form of mRNA therapy, but to that end, it is of utmost importance that all patients with PCD be carefully characterized and given a genetic diagnosis. In this narrative review, we have concentrated on lower airways and summarized the current understanding of the chronic airway disease in this motile ciliopathy. In addition, we highlight the challenges, gaps, and opportunities in PCD lung disease research.

Pediatric unilobar resection in primary ciliary dyskinesia

Primary ciliary dyskinesia (PCD) causes chronic infections and progressive bronchiectasis that can lead to severe lung disease. Because there are no cures or regenerative therapy options for PCD, treatment of severe lung disease in PCD is focused on managing symptoms, including aggressive administration of antibiotics and diligent airway clearance. The Genetic Disorders of Mucociliary Clearance Consortium (GDMCC) does not recommend routine lobectomy, reserving its use for "rare cases of PCD with severe, localized bronchiectasis" and warns that a lobectomy should be treated with caution. However, if aggressive medical management fails, selective surgical removal of severely defective lung may result in maintenance or improvement of pulmonary function. Certainly, the decision to recommend lung resection in the face of chronic bronchiectasis from PCD requires an extensive discussion before it is considered as an alternative treatment. The purpose of this manuscript was to demonstrate that in selected cases of unilobar disease with bronchiectasis that are not responsive to other therapies (antibiotics and airway clearance), removal of localized necrotic areas of the lung along with prophylactic antibiotics can improve the quality of life of children with PCD associated bronchiectasis and improve growth and nutritional status, and pulmonary function.

Alternative inert gas washout outcomes in patients with primary ciliary dyskinesia.

The lung clearance index (LCI) derived from a nitrogen multiple breath washout test (N2-MBW) is a promising tool to assess small airways disease in primary ciliary dyskinesia, but it is difficult to apply in routine clinical settings because of its long measuring time. In this study, we aimed to assess alternative indices derived from shorter washout protocols.49 patients with primary ciliary dyskinesia (mean age 14.7±6.6 years) and 37 controls (mean age 14.3±1.4 years) performed N2-MBW and double-tracer gas (DTG) single-breath washout tests. Global (LCI and moment ratio (M2/M0)), conductive (Scond) and acinar ventilation inhomogeneity (DTG Slope III (SIII-DTG)) were determined for each individual. The main outcomes were 1) the ability to detect abnormal lung function from washout indices (>1.64 z-scores) and 2) measurement duration.The prevalence of abnormal values for LCI2.5% was 37 out of 47 (79%), for LCI5% was 34 out of 47 (72%), for M2/M0 was 34 out of 47 (72%), for Scond was 36 out of 46 (78%) and for SIII-DTG was 12 out of 35 (34%). Mean±sd duration of measurement was 19.8±11.2 min for LCI2.5%, 10.8±4.6 min for LCI5% and 8.6±2.3 min for ScondCompared to standard LCI2.5%, ventilation inhomogeneity was detected by LCI5%, moment ratio and Scond with comparable sensitivity while measurement duration was significantly shorter. Longitudinal studies will show which outcome is most suitable and practical in terms of sensitivity, duration and variability within the course of primary ciliary dyskinesia lung disease.

Primary ciliary dyskinesia. Recent advances in diagnostics, genetics, and characterization of clinical disease.

Primary ciliary dyskinesia (PCD) is a genetically heterogeneous recessive disorder of motile cilia that leads to oto-sino-pulmonary diseases and organ laterality defects in approximately 50% of cases. The estimated incidence of PCD is approximately 1 per 15,000 births, but the prevalence of PCD is difficult to determine, primarily because of limitations in diagnostic methods that focus on testing ciliary ultrastructure and function. Diagnostic capabilities have recently benefitted from (1) documentation of low nasal nitric oxide production in PCD and (2) discovery of biallelic mutations in multiple PCD-causing genes. The use of these complementary diagnostic approaches shows that at least 30% of patients with PCD have normal ciliary ultrastructure. More accurate identification of patients with PCD has also allowed definition of a strong clinical phenotype, which includes neonatal respiratory distress in >80% of cases, daily nasal congestion and wet cough starting soon after birth, and early development of recurrent/chronic middle-ear and sinus disease. Recent studies, using advanced imaging and pulmonary physiologic assessments, clearly demonstrate early onset of lung disease in PCD, with abnormal air flow mechanics by age 6-8 years that is similar to cystic fibrosis, and age-dependent onset of bronchiectasis. The treatment of PCD is not standardized, and there are no validated PCD-specific therapies. Most patients with PCD receive suboptimal management, which should include airway clearance, regular surveillance of pulmonary function and respiratory microbiology, and use of antibiotics targeted to pathogens. The PCD Foundation is developing a network of clinical centers, which should improve diagnosis and management of PCD.

Progression of lung disease in primary ciliary dyskinesia: Is spirometry less accurate than CT?

Despite its extensive use, there is no evidence that spirometry is useful in the assessment of progression of lung disease in primary ciliary dyskinesia (PCD). We hypothesize that high-resolution computed tomography (HRCT) is a better indicator of PCD lung disease progression than spirometry. We retrospectively evaluated two paired spirometry and HRCT examinations from 20 PCD patients (age, 11.6 years; range, 6.5-27.5 years). The evaluations were performed in stable state and during unstable lung disease. HRCT scans were scored blind by two raters. Compared to the first assessment, at the second evaluation spirometry did not change while HRCT scores significantly worsened (P < 0.01). Age was significantly related to HRCT total (r = 0.5; P = 0.02) and bronchiectasis scores (r = 0.5; P = 0.02). At both evaluations, HRCT total score correlated with FEV(1) (r = -0.5, P = 0.01; r = -0.7, P = 0.001, respectively) and FVC Z scores (r = -0.6, P = 0.006; r = -0.7, P = 0.001, respectively), and bronchiectasis score was related to FEV(1) (r = -0.5, P = 0.03; r = -0.6; P = 0.002, respectively) and FVC Z scores (r = -0.6, P = 0.008; r = -0.7, P = 0.001, respectively). No relationship was found between the change in HRCT scores and the change in spirometry. In PCD, structural lung disease may worsen despite spirometry being stable.

A new biological marker isolated and characterizated in sputum from lung pathology patients: microparticles

Sputum is recognized as a very useful sampling method in Cystic Fibrosis (CF) for both research and clinical use aiding both the diagnosis and monitoring of lung disease inflammatory status. A great advantage of the technique is that it enables sampling of the airways in a non-invasive manner. We investigated on the presence and phenotype of microparticles (MPs) in the sputum, of acute and intermittent CF and Primary Ciliary Dyskinesia (PCD) adult patients. MPs are membrane vesicles that are released during cell activation and apoptosis. MPs have different biological effects depending on the cell from they originate. CF lung disease is characterized by massive neutrophil influx in the airways, their activation and eventually apoptosis. Spontaneous sputum, obtained from 21 CF patients (10 acute and 11 intermittent) and 7 patients with PCD, was liquefied with Sputasol. MPs were counted, visualized by electron microscopy, identified in the supernatants of treated sputum by cytofluorimetry and immunodecoration for leukocyte (CD11a), granulocyte (CD66b), and monocyte-macrophage (CD11b) antigens. Electron microscopy revealed that sputum MPs were in the 100-500 nm range and did not contain bacteria. CF sputa contained higher number of MPs in comparison with PCD sputa. CD66b and CD11a, but not CD11b, levels in MPs were significantly higher in CF than in PCD. Acute and intermittent patients presented significantly higher levels of CD11aand CD66b-expressing MPs respect to PCD patients. MPs are detectable in sputa obtained from CF patients and are predominantly of granulocyte origin. These findings are consistent with massive influx of neutrophils into CF airways and their accumulation on the surface of the airway epithelium. In this environment, neutrophils are activated by bacterial products, pro-inflammatory cytokines, and chemokines. Neutrophils undergo apoptosis, as normally happens in acute inflammation, but also postapoptotic necrosis, releasing toxic enzymes and oxygen radicals. MPs in CF sputa likely reflect both activation and apoptosis of neutrophils. The significantly less presence of granulocyte-derived MPs in PCD respect to CF patients, may be due to the fact that lung disease in PCD, although similar, is delayed in time as compared with CF. In CF airways, neutrophil-derived MPs could contribute to self-perpetuating inflammatory cycle, and may account for the exaggerated pro-inflammatory response of cells in CF patients. The MPs isolated from sputum could be a new non invasive methods and opens a new opportunity for the study of lung disease.

Primary Ciliary Dyskinesia

Primary ciliary dyskinesia (PCD) is an inherited disorder characterized by impaired ciliary function that leads to an array of clinical manifestations including chronic bronchitis, chronic sinusitis, chronic otitis media, situs inversus (in approximately 50% of cases), and infertility. The underlying genetic and molecular defects have not been defined. Molecular genetic studies have demonstrated multiple gene loci. In a few families, defects in genes encoding ciliary dynein proteins have been identified. PCD is an interesting disease to compare with cystic fibrosis (CF) because both are airway diseases associated with impaired mucociliary clearance and with chronic infection of the airways leading to bronchiectasis as well as chronic infection of the sinuses that may be associated with nasal polyposis. The progression of the lower airway disease appears less rapid in PCD. Unlike CF, PCD is commonly associated with chronic otitis media, respiratory problems during the neonatal period, and situs inversus, suggesting that ciliary function is also important for clearing fluid/bacteria from the middle ear, for clearing fluid from the fetal lung during the transition to an air-filled neonatal lung, and for directing laterality of organs during embryonic development. The management for PCD lung disease is similar to that for CF and other diseases with chronic bronchitis leading to bronchiectasis.